Avoid unecessary MemSet call (src/backend/utils/cache/relcache.c)

diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index 60e72f9e8b..6da7a5cf7f 100644
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -6265,7 +6265,7 @@ load_relcache_init_file(bool shared)
 		rel->rd_firstRelfilenodeSubid = InvalidSubTransactionId;
 		rel->rd_droppedSubid = InvalidSubTransactionId;
 		rel->rd_amcache = NULL;
-		MemSet(&rel->pgstat_info, 0, sizeof(rel->pgstat_info));
+		rel->pgstat_info = NULL;

diff --git a/contrib/bloom/blcost.c b/contrib/bloom/blcost.c
index d42e4e9628..b35e96ea20 100644
--- a/contrib/bloom/blcost.c
+++ b/contrib/bloom/blcost.c
@@ -28,7 +28,7 @@ blcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	IndexOptInfo *index = path->indexinfo;
 	GenericCosts costs;
 
-	MemSet(&costs, 0, sizeof(costs));
+	MemSet(&costs, 0, sizeof(GenericCosts));
 
 	/* We have to visit all index tuples anyway */
 	costs.numIndexTuples = index->tuples;
diff --git a/contrib/bloom/blinsert.c b/contrib/bloom/blinsert.c
index 82378db441..b80c47cd65 100644
--- a/contrib/bloom/blinsert.c
+++ b/contrib/bloom/blinsert.c
@@ -132,7 +132,7 @@ blbuild(Relation heap, Relation index, IndexInfo *indexInfo)
 	BloomInitMetapage(index);
 
 	/* Initialize the bloom build state */
-	memset(&buildstate, 0, sizeof(buildstate));
+	memset(&buildstate, 0, sizeof(BloomBuildState));
 	initBloomState(&buildstate.blstate, index);
 	buildstate.tmpCtx = AllocSetContextCreate(CurrentMemoryContext,
 											  "Bloom build temporary context",
diff --git a/contrib/intarray/_int_selfuncs.c b/contrib/intarray/_int_selfuncs.c
index 3d8ff6781b..4ec42e9edf 100644
--- a/contrib/intarray/_int_selfuncs.c
+++ b/contrib/intarray/_int_selfuncs.c
@@ -221,7 +221,7 @@ _int_matchsel(PG_FUNCTION_ARGS)
 		}
 	}
 	else
-		memset(&sslot, 0, sizeof(sslot));
+		memset(&sslot, 0, sizeof(AttStatsSlot));
 
 	/* Process the logical expression in the query, using the stats */
 	selec = int_query_opr_selec(GETQUERY(query) + query->size - 1,
diff --git a/contrib/pg_trgm/trgm_regexp.c b/contrib/pg_trgm/trgm_regexp.c
index 58d32ba946..adabb3d8cd 100644
--- a/contrib/pg_trgm/trgm_regexp.c
+++ b/contrib/pg_trgm/trgm_regexp.c
@@ -926,7 +926,7 @@ transformGraph(TrgmNFA *trgmNFA)
 	trgmNFA->nstates = 0;
 
 	/* Create initial state: ambiguous prefix, NFA's initial state */
-	MemSet(&initkey, 0, sizeof(initkey));
+	MemSet(&initkey, 0, sizeof(TrgmStateKey));
 	initkey.prefix.colors[0] = COLOR_UNKNOWN;
 	initkey.prefix.colors[1] = COLOR_UNKNOWN;
 	initkey.nstate = pg_reg_getinitialstate(trgmNFA->regex);
@@ -1028,7 +1028,7 @@ addKey(TrgmNFA *trgmNFA, TrgmState *state, TrgmStateKey *key)
 	 * Ensure any pad bytes in destKey are zero, since it may get used as a
 	 * hashtable key by getState.
 	 */
-	MemSet(&destKey, 0, sizeof(destKey));
+	MemSet(&destKey, 0, sizeof(TrgmStateKey));
 
 	/*
 	 * Compare key to each existing enter key of the state to check for
@@ -1209,7 +1209,7 @@ addArcs(TrgmNFA *trgmNFA, TrgmState *state)
 	 * Ensure any pad bytes in destKey are zero, since it may get used as a
 	 * hashtable key by getState.
 	 */
-	MemSet(&destKey, 0, sizeof(destKey));
+	MemSet(&destKey, 0, sizeof(TrgmStateKey));
 
 	/*
 	 * Iterate over enter keys associated with this expanded-graph state. This
diff --git a/contrib/pgcrypto/crypt-blowfish.c b/contrib/pgcrypto/crypt-blowfish.c
index a663852ccf..63fcef562d 100644
--- a/contrib/pgcrypto/crypt-blowfish.c
+++ b/contrib/pgcrypto/crypt-blowfish.c
@@ -750,7 +750,7 @@ _crypt_blowfish_rn(const char *key, const char *setting,
 /* Overwrite the most obvious sensitive data we have on the stack. Note
  * that this does not guarantee there's no sensitive data left on the
  * stack and/or in registers; I'm not aware of portable code that does. */
-	px_memset(&data, 0, sizeof(data));
+	px_memset(&data, 0, sizeof(struct data));
 
 	return output;
 }
diff --git a/contrib/pgstattuple/pgstatindex.c b/contrib/pgstattuple/pgstatindex.c
index e1048e47ff..87be62f023 100644
--- a/contrib/pgstattuple/pgstatindex.c
+++ b/contrib/pgstattuple/pgstatindex.c
@@ -601,7 +601,7 @@ pgstathashindex(PG_FUNCTION_ARGS)
 				 errmsg("cannot access temporary indexes of other sessions")));
 
 	/* Get the information we need from the metapage. */
-	memset(&stats, 0, sizeof(stats));
+	memset(&stats, 0, sizeof(HashIndexStat));
 	metabuf = _hash_getbuf(rel, HASH_METAPAGE, HASH_READ, LH_META_PAGE);
 	metap = HashPageGetMeta(BufferGetPage(metabuf));
 	stats.version = metap->hashm_version;
diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c
index 061ffaf329..20a8162268 100644
--- a/contrib/postgres_fdw/connection.c
+++ b/contrib/postgres_fdw/connection.c
@@ -311,7 +311,7 @@ make_new_connection(ConnCacheEntry *entry, UserMapping *user)
 	entry->mapping_hashvalue =
 		GetSysCacheHashValue1(USERMAPPINGOID,
 							  ObjectIdGetDatum(user->umid));
-	memset(&entry->state, 0, sizeof(entry->state));
+	memset(&entry->state, 0, sizeof(PgFdwConnState));
 
 	/*
 	 * Determine whether to keep the connection that we're about to make here
@@ -1533,7 +1533,7 @@ pgfdw_abort_cleanup(ConnCacheEntry *entry, bool toplevel)
 	 * fetch_more_data(); in that case reset the per-connection state here.
 	 */
 	if (entry->state.pendingAreq)
-		memset(&entry->state, 0, sizeof(entry->state));
+		memset(&entry->state, 0, sizeof(PgFdwConnState));
 
 	/* Disarm changing_xact_state if it all worked */
 	entry->changing_xact_state = false;
diff --git a/contrib/sepgsql/hooks.c b/contrib/sepgsql/hooks.c
index 97e61b8043..2882ddb377 100644
--- a/contrib/sepgsql/hooks.c
+++ b/contrib/sepgsql/hooks.c
@@ -480,5 +480,5 @@ _PG_init(void)
 	ProcessUtility_hook = sepgsql_utility_command;
 
 	/* init contextual info */
-	memset(&sepgsql_context_info, 0, sizeof(sepgsql_context_info));
+	memset(&sepgsql_context_info, 0, sizeof(sepgsql_context_info_t));
 }
diff --git a/src/backend/access/common/scankey.c b/src/backend/access/common/scankey.c
index ff2b608f2e..e761f17dd2 100644
--- a/src/backend/access/common/scankey.c
+++ b/src/backend/access/common/scankey.c
@@ -51,7 +51,7 @@ ScanKeyEntryInitialize(ScanKey entry,
 	else
 	{
 		Assert(flags & (SK_SEARCHNULL | SK_SEARCHNOTNULL));
-		MemSet(&entry->sk_func, 0, sizeof(entry->sk_func));
+		MemSet(&entry->sk_func, 0, sizeof(FmgrInfo));
 	}
 }
 
diff --git a/src/backend/access/gin/ginfast.c b/src/backend/access/gin/ginfast.c
index 7409fdc165..8119baaacb 100644
--- a/src/backend/access/gin/ginfast.c
+++ b/src/backend/access/gin/ginfast.c
@@ -1058,7 +1058,7 @@ gin_clean_pending_list(PG_FUNCTION_ARGS)
 		aclcheck_error(ACLCHECK_NOT_OWNER, OBJECT_INDEX,
 					   RelationGetRelationName(indexRel));
 
-	memset(&stats, 0, sizeof(stats));
+	memset(&stats, 0, sizeof(IndexBulkDeleteResult));
 	initGinState(&ginstate, indexRel);
 	ginInsertCleanup(&ginstate, true, true, true, &stats);
 
diff --git a/src/backend/access/gin/ginvacuum.c b/src/backend/access/gin/ginvacuum.c
index b4fa5f6bf8..451fe28ff1 100644
--- a/src/backend/access/gin/ginvacuum.c
+++ b/src/backend/access/gin/ginvacuum.c
@@ -721,7 +721,7 @@ ginvacuumcleanup(IndexVacuumInfo *info, IndexBulkDeleteResult *stats)
 						 false, true, stats);
 	}
 
-	memset(&idxStat, 0, sizeof(idxStat));
+	memset(&idxStat, 0, sizeof(GinStatsData));
 
 	/*
 	 * XXX we always report the heap tuple count as the number of index
diff --git a/src/backend/access/heap/rewriteheap.c b/src/backend/access/heap/rewriteheap.c
index 2a53826736..01989d79a2 100644
--- a/src/backend/access/heap/rewriteheap.c
+++ b/src/backend/access/heap/rewriteheap.c
@@ -411,7 +411,7 @@ rewrite_heap_tuple(RewriteState state,
 	{
 		OldToNewMapping mapping;
 
-		memset(&hashkey, 0, sizeof(hashkey));
+		memset(&hashkey, 0, sizeof(TidHashKey));
 		hashkey.xmin = HeapTupleHeaderGetUpdateXid(old_tuple->t_data);
 		hashkey.tid = old_tuple->t_data->t_ctid;
 
@@ -493,7 +493,7 @@ rewrite_heap_tuple(RewriteState state,
 			 */
 			UnresolvedTup unresolved;
 
-			memset(&hashkey, 0, sizeof(hashkey));
+			memset(&hashkey, 0, sizeof(TidHashKey));
 			hashkey.xmin = HeapTupleHeaderGetXmin(new_tuple->t_data);
 			hashkey.tid = old_tid;
 
@@ -581,7 +581,7 @@ rewrite_heap_dead_tuple(RewriteState state, HeapTuple old_tuple)
 	TidHashKey	hashkey;
 	bool		found;
 
-	memset(&hashkey, 0, sizeof(hashkey));
+	memset(&hashkey, 0, sizeof(TidHashKey));
 	hashkey.xmin = HeapTupleHeaderGetXmin(old_tuple->t_data);
 	hashkey.tid = old_tuple->t_self;
 
diff --git a/src/backend/access/spgist/spgdoinsert.c b/src/backend/access/spgist/spgdoinsert.c
index e84b5edc03..6194a92542 100644
--- a/src/backend/access/spgist/spgdoinsert.c
+++ b/src/backend/access/spgist/spgdoinsert.c
@@ -818,7 +818,7 @@ doPickSplit(Relation index, SpGistState *state,
 	oldLeafs[in.nTuples] = newLeafTuple;
 	in.nTuples++;
 
-	memset(&out, 0, sizeof(out));
+	memset(&out, 0, sizeof(spgPickSplitOut));
 
 	if (!isNulls)
 	{
@@ -2185,7 +2185,7 @@ spgdoinsert(Relation index, SpGistState *state,
 			in.nNodes = innerTuple->nNodes;
 			in.nodeLabels = spgExtractNodeLabels(state, innerTuple);
 
-			memset(&out, 0, sizeof(out));
+			memset(&out, 0, sizeof(spgChooseOut));
 
 			if (!isnull)
 			{
diff --git a/src/backend/access/spgist/spgscan.c b/src/backend/access/spgist/spgscan.c
index 87a345d290..888722f9e3 100644
--- a/src/backend/access/spgist/spgscan.c
+++ b/src/backend/access/spgist/spgscan.c
@@ -672,7 +672,7 @@ spgInnerTest(SpGistScanOpaque so, SpGistSearchItem *item,
 	int			nNodes = innerTuple->nNodes;
 	int			i;
 
-	memset(&out, 0, sizeof(out));
+	memset(&out, 0, sizeof(spgInnerConsistentOut));
 
 	if (!isnull)
 	{
diff --git a/src/backend/access/spgist/spgvalidate.c b/src/backend/access/spgist/spgvalidate.c
index 82281f7b83..5167f60454 100644
--- a/src/backend/access/spgist/spgvalidate.c
+++ b/src/backend/access/spgist/spgvalidate.c
@@ -112,7 +112,7 @@ spgvalidate(Oid opclassoid)
 				ok = check_amproc_signature(procform->amproc, VOIDOID, true,
 											2, 2, INTERNALOID, INTERNALOID);
 				configIn.attType = procform->amproclefttype;
-				memset(&configOut, 0, sizeof(configOut));
+				memset(&configOut, 0, sizeof(spgConfigOut));
 
 				OidFunctionCall2(procform->amproc,
 								 PointerGetDatum(&configIn),
diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index df0cd77558..3575a17ed2 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -557,7 +557,7 @@ LaunchParallelWorkers(ParallelContext *pcxt)
 	oldcontext = MemoryContextSwitchTo(TopTransactionContext);
 
 	/* Configure a worker. */
-	memset(&worker, 0, sizeof(worker));
+	memset(&worker, 0, sizeof(BackgroundWorker));
 	snprintf(worker.bgw_name, BGW_MAXLEN, "parallel worker for PID %d",
 			 MyProcPid);
 	snprintf(worker.bgw_type, BGW_MAXLEN, "parallel worker");
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 71136b11a2..afb918f13b 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -6302,7 +6302,7 @@ CreateCheckPoint(int flags)
 	 * checkpoint proceeds, we always accumulate stats, even if
 	 * log_checkpoints is currently off.
 	 */
-	MemSet(&CheckpointStats, 0, sizeof(CheckpointStats));
+	MemSet(&CheckpointStats, 0, sizeof(CheckpointStatsData));
 	CheckpointStats.ckpt_start_t = GetCurrentTimestamp();
 
 	/*
@@ -6327,7 +6327,7 @@ CreateCheckPoint(int flags)
 	}
 
 	/* Begin filling in the checkpoint WAL record */
-	MemSet(&checkPoint, 0, sizeof(checkPoint));
+	MemSet(&checkPoint, 0, sizeof(CheckPoint));
 	checkPoint.time = (pg_time_t) time(NULL);
 
 	/*
@@ -6999,7 +6999,7 @@ CreateRestartPoint(int flags)
 	 * checkpoint proceeds, we always accumulate stats, even if
 	 * log_checkpoints is currently off.
 	 */
-	MemSet(&CheckpointStats, 0, sizeof(CheckpointStats));
+	MemSet(&CheckpointStats, 0, sizeof(CheckpointStatsData));
 	CheckpointStats.ckpt_start_t = GetCurrentTimestamp();
 
 	if (log_checkpoints)
diff --git a/src/backend/catalog/dependency.c b/src/backend/catalog/dependency.c
index de10923391..219dc21b28 100644
--- a/src/backend/catalog/dependency.c
+++ b/src/backend/catalog/dependency.c
@@ -572,8 +572,8 @@ findDependentObjects(const ObjectAddress *object,
 							  NULL, nkeys, key);
 
 	/* initialize variables that loop may fill */
-	memset(&owningObject, 0, sizeof(owningObject));
-	memset(&partitionObject, 0, sizeof(partitionObject));
+	memset(&owningObject, 0, sizeof(ObjectAddress));
+	memset(&partitionObject, 0, sizeof(ObjectAddress));
 
 	while (HeapTupleIsValid(tup = systable_getnext(scan)))
 	{
@@ -997,7 +997,7 @@ findDependentObjects(const ObjectAddress *object,
 	else if (stack)
 		extra.dependee = *stack->object;
 	else
-		memset(&extra.dependee, 0, sizeof(extra.dependee));
+		memset(&extra.dependee, 0, sizeof(ObjectAddress));
 	add_exact_object_address_extra(object, &extra, targetObjects);
 }
 
@@ -1640,7 +1640,7 @@ recordDependencyOnSingleRelExpr(const ObjectAddress *depender,
 	context.addrs = new_object_addresses();
 
 	/* We gin up a rather bogus rangetable list to handle Vars */
-	MemSet(&rte, 0, sizeof(rte));
+	MemSet(&rte, 0, sizeof(RangeTblEntry));
 	rte.type = T_RangeTblEntry;
 	rte.rtekind = RTE_RELATION;
 	rte.relid = relId;
diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c
index 2da6b75a15..e9eeab9727 100644
--- a/src/backend/commands/analyze.c
+++ b/src/backend/commands/analyze.c
@@ -2394,7 +2394,7 @@ compute_scalar_stats(VacAttrStatsP stats,
 	tupnoLink = (int *) palloc(samplerows * sizeof(int));
 	track = (ScalarMCVItem *) palloc(num_mcv * sizeof(ScalarMCVItem));
 
-	memset(&ssup, 0, sizeof(ssup));
+	memset(&ssup, 0, sizeof(SortSupportData));
 	ssup.ssup_cxt = CurrentMemoryContext;
 	ssup.ssup_collation = stats->attrcollid;
 	ssup.ssup_nulls_first = false;
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 2de0ebacec..5b837a0ee3 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -11508,7 +11508,7 @@ validateForeignKeyConstraint(char *conname,
 	/*
 	 * Build a trigger call structure; we'll need it either way.
 	 */
-	MemSet(&trig, 0, sizeof(trig));
+	MemSet(&trig, 0, sizeof(Trigger));
 	trig.tgoid = InvalidOid;
 	trig.tgname = conname;
 	trig.tgenabled = TRIGGER_FIRES_ON_ORIGIN;
@@ -19231,7 +19231,7 @@ ATDetachCheckNoForeignKeyRefs(Relation partition)
 		/* prevent data changes into the referencing table until commit */
 		rel = table_open(constrForm->conrelid, ShareLock);
 
-		MemSet(&trig, 0, sizeof(trig));
+		MemSet(&trig, 0, sizeof(Trigger));
 		trig.tgoid = InvalidOid;
 		trig.tgname = NameStr(constrForm->conname);
 		trig.tgenabled = TRIGGER_FIRES_ON_ORIGIN;
diff --git a/src/backend/commands/typecmds.c b/src/backend/commands/typecmds.c
index 9b92b04242..a2d9904568 100644
--- a/src/backend/commands/typecmds.c
+++ b/src/backend/commands/typecmds.c
@@ -4119,7 +4119,7 @@ AlterType(AlterTypeStmt *stmt)
 	typForm = (Form_pg_type) GETSTRUCT(tup);
 
 	/* Process options */
-	memset(&atparams, 0, sizeof(atparams));
+	memset(&atparams, 0, sizeof(AlterTypeRecurseParams));
 	foreach(pl, stmt->options)
 	{
 		DefElem    *defel = (DefElem *) lfirst(pl);
@@ -4441,7 +4441,7 @@ AlterTypeRecurse(Oid typeOid, bool isImplicitArray,
 			if (!HeapTupleIsValid(arrtup))
 				elog(ERROR, "cache lookup failed for type %u", arrtypoid);
 
-			memset(&arrparams, 0, sizeof(arrparams));
+			memset(&arrparams, 0, sizeof(AlterTypeRecurseParams));
 			arrparams.updateTypmodin = atparams->updateTypmodin;
 			arrparams.updateTypmodout = atparams->updateTypmodout;
 			arrparams.typmodinOid = atparams->typmodinOid;
diff --git a/src/backend/executor/execExpr.c b/src/backend/executor/execExpr.c
index 2831e7978b..a9d6cc4e07 100644
--- a/src/backend/executor/execExpr.c
+++ b/src/backend/executor/execExpr.c
@@ -3163,7 +3163,7 @@ ExecInitSubscriptingRef(ExprEvalStep *scratch, SubscriptingRef *sbsref,
 	 * execution steps below; and it can optionally set up some data pointed
 	 * to by the workspace field.
 	 */
-	memset(&methods, 0, sizeof(methods));
+	memset(&methods, 0, sizeof(SubscriptExecSteps));
 	sbsroutines->exec_setup(sbsref, sbsrefstate, &methods);
 
 	/*
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index 29bc26669b..701ef3e132 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -611,7 +611,7 @@ SPI_execute(const char *src, bool read_only, long tcount)
 
 	_SPI_prepare_oneshot_plan(src, &plan);
 
-	memset(&options, 0, sizeof(options));
+	memset(&options, 0, sizeof(SPIExecuteOptions));
 	options.read_only = read_only;
 	options.tcount = tcount;
 
@@ -683,7 +683,7 @@ SPI_execute_plan(SPIPlanPtr plan, Datum *Values, const char *Nulls,
 	if (res < 0)
 		return res;
 
-	memset(&options, 0, sizeof(options));
+	memset(&options, 0, sizeof(SPIExecuteOptions));
 	options.params = _SPI_convert_params(plan->nargs, plan->argtypes,
 										 Values, Nulls);
 	options.read_only = read_only;
@@ -741,7 +741,7 @@ SPI_execute_plan_with_paramlist(SPIPlanPtr plan, ParamListInfo params,
 	if (res < 0)
 		return res;
 
-	memset(&options, 0, sizeof(options));
+	memset(&options, 0, sizeof(SPIExecuteOptions));
 	options.params = params;
 	options.read_only = read_only;
 	options.tcount = tcount;
@@ -786,7 +786,7 @@ SPI_execute_snapshot(SPIPlanPtr plan,
 	if (res < 0)
 		return res;
 
-	memset(&options, 0, sizeof(options));
+	memset(&options, 0, sizeof(SPIExecuteOptions));
 	options.params = _SPI_convert_params(plan->nargs, plan->argtypes,
 										 Values, Nulls);
 	options.read_only = read_only;
@@ -841,7 +841,7 @@ SPI_execute_with_args(const char *src,
 
 	_SPI_prepare_oneshot_plan(src, &plan);
 
-	memset(&options, 0, sizeof(options));
+	memset(&options, 0, sizeof(SPIExecuteOptions));
 	options.params = paramLI;
 	options.read_only = read_only;
 	options.tcount = tcount;
diff --git a/src/backend/libpq/auth.c b/src/backend/libpq/auth.c
index efc53f3135..450ea73b22 100644
--- a/src/backend/libpq/auth.c
+++ b/src/backend/libpq/auth.c
@@ -3041,7 +3041,7 @@ PerformRadiusTransaction(const char *server, const char *secret, const char *por
 	if (identifier == NULL)
 		identifier = "postgresql";
 
-	MemSet(&hint, 0, sizeof(hint));
+	MemSet(&hint, 0, sizeof(struct addrinfo));
 	hint.ai_socktype = SOCK_DGRAM;
 	hint.ai_family = AF_UNSPEC;
 	port = atoi(portstr);
@@ -3133,8 +3133,8 @@ PerformRadiusTransaction(const char *server, const char *secret, const char *por
 		return STATUS_ERROR;
 	}
 
-	memset(&localaddr, 0, sizeof(localaddr));
 #ifdef HAVE_IPV6
+	memset(&localaddr, 0, sizeof(struct sockaddr_in6));
 	localaddr.sin6_family = serveraddrs[0].ai_family;
 	localaddr.sin6_addr = in6addr_any;
 	if (localaddr.sin6_family == AF_INET6)
@@ -3142,6 +3142,7 @@ PerformRadiusTransaction(const char *server, const char *secret, const char *por
 	else
 		addrsize = sizeof(struct sockaddr_in);
 #else
+	memset(&localaddr, 0, sizeof(struct sockaddr_in));
 	localaddr.sin_family = serveraddrs[0].ai_family;
 	localaddr.sin_addr.s_addr = INADDR_ANY;
 	addrsize = sizeof(struct sockaddr_in);
diff --git a/src/backend/libpq/hba.c b/src/backend/libpq/hba.c
index 327a4b42af..eb67505180 100644
--- a/src/backend/libpq/hba.c
+++ b/src/backend/libpq/hba.c
@@ -1964,7 +1964,7 @@ parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline,
 		/* For each entry in the list, translate it */
 		foreach(l, parsed_servers)
 		{
-			MemSet(&hints, 0, sizeof(hints));
+			MemSet(&hints, 0, sizeof(struct addrinfo));
 			hints.ai_socktype = SOCK_DGRAM;
 			hints.ai_family = AF_UNSPEC;
 
diff --git a/src/backend/libpq/ifaddr.c b/src/backend/libpq/ifaddr.c
index a41808aff0..346620ef33 100644
--- a/src/backend/libpq/ifaddr.c
+++ b/src/backend/libpq/ifaddr.c
@@ -137,7 +137,7 @@ pg_sockaddr_cidr_mask(struct sockaddr_storage *mask, char *numbits, int family)
 
 				if (bits < 0 || bits > 32)
 					return -1;
-				memset(&mask4, 0, sizeof(mask4));
+				memset(&mask4, 0, sizeof(struct sockaddr_in));
 				/* avoid "x << 32", which is not portable */
 				if (bits > 0)
 					maskl = (0xffffffffUL << (32 - (int) bits))
@@ -157,7 +157,7 @@ pg_sockaddr_cidr_mask(struct sockaddr_storage *mask, char *numbits, int family)
 
 				if (bits < 0 || bits > 128)
 					return -1;
-				memset(&mask6, 0, sizeof(mask6));
+				memset(&mask6, 0, sizeof(struct sockaddr_in6));
 				for (i = 0; i < 16; i++)
 				{
 					if (bits <= 0)
@@ -387,7 +387,7 @@ pg_foreach_ifaddr(PgIfAddrCallback callback, void *cb_data)
 			return -1;
 		}
 
-		memset(&lifc, 0, sizeof(lifc));
+		memset(&lifc, 0, sizeof(struct lifconf));
 		lifc.lifc_family = AF_UNSPEC;
 		lifc.lifc_buf = buffer = ptr;
 		lifc.lifc_len = n_buffer;
@@ -508,7 +508,7 @@ pg_foreach_ifaddr(PgIfAddrCallback callback, void *cb_data)
 			return -1;
 		}
 
-		memset(&ifc, 0, sizeof(ifc));
+		memset(&ifc, 0, sizeof(struct ifconf));
 		ifc.ifc_buf = buffer = ptr;
 		ifc.ifc_len = n_buffer;
 
@@ -566,10 +566,10 @@ pg_foreach_ifaddr(PgIfAddrCallback callback, void *cb_data)
 #endif
 
 	/* addr 127.0.0.1/8 */
-	memset(&addr, 0, sizeof(addr));
+	memset(&addr, 0, sizeof(struct sockaddr_in));
 	addr.sin_family = AF_INET;
 	addr.sin_addr.s_addr = pg_ntoh32(0x7f000001);
-	memset(&mask, 0, sizeof(mask));
+	memset(&mask, 0, sizeof(struct sockaddr_storage));
 	pg_sockaddr_cidr_mask(&mask, "8", AF_INET);
 	run_ifaddr_callback(callback, cb_data,
 						(struct sockaddr *) &addr,
@@ -577,10 +577,10 @@ pg_foreach_ifaddr(PgIfAddrCallback callback, void *cb_data)
 
 #ifdef HAVE_IPV6
 	/* addr ::1/128 */
-	memset(&addr6, 0, sizeof(addr6));
+	memset(&addr6, 0, sizeof(struct sockaddr_in6));
 	addr6.sin6_family = AF_INET6;
 	addr6.sin6_addr.s6_addr[15] = 1;
-	memset(&mask, 0, sizeof(mask));
+	memset(&mask, 0, sizeof(struct sockaddr_storage));
 	pg_sockaddr_cidr_mask(&mask, "128", AF_INET6);
 	run_ifaddr_callback(callback, cb_data,
 						(struct sockaddr *) &addr6,
diff --git a/src/backend/libpq/pqcomm.c b/src/backend/libpq/pqcomm.c
index 75392a8bb7..ed041b79eb 100644
--- a/src/backend/libpq/pqcomm.c
+++ b/src/backend/libpq/pqcomm.c
@@ -343,7 +343,7 @@ StreamServerPort(int family, const char *hostName, unsigned short portNumber,
 #endif
 
 	/* Initialize hint structure */
-	MemSet(&hint, 0, sizeof(hint));
+	MemSet(&hint, 0, sizeof(struct addrinfo));
 	hint.ai_family = family;
 	hint.ai_flags = AI_PASSIVE;
 	hint.ai_socktype = SOCK_STREAM;
diff --git a/src/backend/optimizer/path/allpaths.c b/src/backend/optimizer/path/allpaths.c
index 7ac116a791..77f1d0665f 100644
--- a/src/backend/optimizer/path/allpaths.c
+++ b/src/backend/optimizer/path/allpaths.c
@@ -2467,7 +2467,7 @@ set_subquery_pathlist(PlannerInfo *root, RelOptInfo *rel,
 	 * will be set true if we find that output column i of the subquery is
 	 * unsafe to use in a pushed-down qual.
 	 */
-	memset(&safetyInfo, 0, sizeof(safetyInfo));
+	memset(&safetyInfo, 0, sizeof(pushdown_safety_info));
 	safetyInfo.unsafeColumns = (bool *)
 		palloc0((list_length(subquery->targetList) + 1) * sizeof(bool));
 
diff --git a/src/backend/optimizer/path/indxpath.c b/src/backend/optimizer/path/indxpath.c
index 0ef70ad7f1..f78d38e019 100644
--- a/src/backend/optimizer/path/indxpath.c
+++ b/src/backend/optimizer/path/indxpath.c
@@ -269,7 +269,7 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
 		/*
 		 * Identify the restriction clauses that can match the index.
 		 */
-		MemSet(&rclauseset, 0, sizeof(rclauseset));
+		MemSet(&rclauseset, 0, sizeof(IndexClauseSet));
 		match_restriction_clauses_to_index(root, index, &rclauseset);
 
 		/*
@@ -286,7 +286,7 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
 		 * step finds only "loose" join clauses that have not been merged into
 		 * EquivalenceClasses.  Also, collect join OR clauses for later.
 		 */
-		MemSet(&jclauseset, 0, sizeof(jclauseset));
+		MemSet(&jclauseset, 0, sizeof(IndexClauseSet));
 		match_join_clauses_to_index(root, rel, index,
 									&jclauseset, &joinorclauses);
 
@@ -294,7 +294,7 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
 		 * Look for EquivalenceClasses that can generate joinclauses matching
 		 * the index.
 		 */
-		MemSet(&eclauseset, 0, sizeof(eclauseset));
+		MemSet(&eclauseset, 0, sizeof(IndexClauseSet));
 		match_eclass_clauses_to_index(root, index,
 									  &eclauseset);
 
@@ -616,7 +616,7 @@ get_join_index_paths(PlannerInfo *root, RelOptInfo *rel,
 		return;
 
 	/* Identify indexclauses usable with this relids set */
-	MemSet(&clauseset, 0, sizeof(clauseset));
+	MemSet(&clauseset, 0, sizeof(IndexClauseSet));
 
 	for (indexcol = 0; indexcol < index->nkeycolumns; indexcol++)
 	{
@@ -1211,7 +1211,7 @@ build_paths_for_OR(PlannerInfo *root, RelOptInfo *rel,
 		/*
 		 * Identify the restriction clauses that can match the index.
 		 */
-		MemSet(&clauseset, 0, sizeof(clauseset));
+		MemSet(&clauseset, 0, sizeof(IndexClauseSet));
 		match_clauses_to_index(root, clauses, index, &clauseset);
 
 		/*
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c
index a0f2390334..598bf3960a 100644
--- a/src/backend/optimizer/plan/planner.c
+++ b/src/backend/optimizer/plan/planner.c
@@ -5915,12 +5915,12 @@ expression_planner_with_deps(Expr *expr,
 	PlannerInfo root;
 
 	/* Make up dummy planner state so we can use setrefs machinery */
-	MemSet(&glob, 0, sizeof(glob));
+	MemSet(&glob, 0, sizeof(PlannerGlobal));
 	glob.type = T_PlannerGlobal;
 	glob.relationOids = NIL;
 	glob.invalItems = NIL;
 
-	MemSet(&root, 0, sizeof(root));
+	MemSet(&root, 0, sizeof(PlannerInfo));
 	root.type = T_PlannerInfo;
 	root.glob = &glob;
 
diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c
index d95fd89807..eabeacb0e5 100644
--- a/src/backend/optimizer/plan/setrefs.c
+++ b/src/backend/optimizer/plan/setrefs.c
@@ -3274,14 +3274,14 @@ extract_query_dependencies(Node *query,
 	PlannerInfo root;
 
 	/* Make up dummy planner state so we can use this module's machinery */
-	MemSet(&glob, 0, sizeof(glob));
+	MemSet(&glob, 0, sizeof(PlannerGlobal));
 	glob.type = T_PlannerGlobal;
 	glob.relationOids = NIL;
 	glob.invalItems = NIL;
 	/* Hack: we use glob.dependsOnRole to collect hasRowSecurity flags */
 	glob.dependsOnRole = false;
 
-	MemSet(&root, 0, sizeof(root));
+	MemSet(&root, 0, sizeof(PlannerInfo));
 	root.type = T_PlannerInfo;
 	root.glob = &glob;
 
diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c
index 2a1d44b813..375714154a 100644
--- a/src/backend/parser/parse_target.c
+++ b/src/backend/parser/parse_target.c
@@ -1596,7 +1596,7 @@ expandRecordVariable(ParseState *pstate, Var *var, int levelsup)
 					 */
 					ParseState	mypstate;
 
-					MemSet(&mypstate, 0, sizeof(mypstate));
+					MemSet(&mypstate, 0, sizeof(ParseState));
 					mypstate.parentParseState = pstate;
 					mypstate.p_rtable = rte->subquery->rtable;
 					/* don't bother filling the rest of the fake pstate */
@@ -1652,7 +1652,7 @@ expandRecordVariable(ParseState *pstate, Var *var, int levelsup)
 					ParseState	mypstate;
 					Index		levelsup;
 
-					MemSet(&mypstate, 0, sizeof(mypstate));
+					MemSet(&mypstate, 0, sizeof(ParseState));
 					/* this loop must work, since GetCTEForRTE did */
 					for (levelsup = 0;
 						 levelsup < rte->ctelevelsup + netlevelsup;
diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index 3b73e26956..76ba287da4 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -4525,7 +4525,7 @@ postmaster_forkexec(int argc, char *argv[])
 	Port		port;
 
 	/* This entry point passes dummy values for the Port variables */
-	memset(&port, 0, sizeof(port));
+	memset(&port, 0, sizeof(Port));
 	return internal_forkexec(argc, argv, &port);
 }
 
diff --git a/src/backend/replication/logical/launcher.c b/src/backend/replication/logical/launcher.c
index bd5f78cf9a..14014461a1 100644
--- a/src/backend/replication/logical/launcher.c
+++ b/src/backend/replication/logical/launcher.c
@@ -391,7 +391,7 @@ retry:
 	LWLockRelease(LogicalRepWorkerLock);
 
 	/* Register the new dynamic worker. */
-	memset(&bgw, 0, sizeof(bgw));
+	memset(&bgw, 0, sizeof(BackgroundWorker));
 	bgw.bgw_flags = BGWORKER_SHMEM_ACCESS |
 		BGWORKER_BACKEND_DATABASE_CONNECTION;
 	bgw.bgw_start_time = BgWorkerStart_RecoveryFinished;
@@ -710,7 +710,7 @@ ApplyLauncherRegister(void)
 	if (max_logical_replication_workers == 0)
 		return;
 
-	memset(&bgw, 0, sizeof(bgw));
+	memset(&bgw, 0, sizeof(BackgroundWorker));
 	bgw.bgw_flags = BGWORKER_SHMEM_ACCESS |
 		BGWORKER_BACKEND_DATABASE_CONNECTION;
 	bgw.bgw_start_time = BgWorkerStart_RecoveryFinished;
diff --git a/src/backend/replication/logical/origin.c b/src/backend/replication/logical/origin.c
index 21937ab2d3..524b880f78 100644
--- a/src/backend/replication/logical/origin.c
+++ b/src/backend/replication/logical/origin.c
@@ -615,7 +615,7 @@ CheckPointReplicationOrigin(void)
 			continue;
 
 		/* zero, to avoid uninitialized padding bytes */
-		memset(&disk_state, 0, sizeof(disk_state));
+		memset(&disk_state, 0, sizeof(ReplicationStateOnDisk));
 
 		LWLockAcquire(&curstate->lock, LW_SHARED);
 
diff --git a/src/backend/replication/logical/reorderbuffer.c b/src/backend/replication/logical/reorderbuffer.c
index 8da5f9089c..628087c417 100644
--- a/src/backend/replication/logical/reorderbuffer.c
+++ b/src/backend/replication/logical/reorderbuffer.c
@@ -314,7 +314,7 @@ ReorderBufferAllocate(void)
 	buffer =
 		(ReorderBuffer *) MemoryContextAlloc(new_ctx, sizeof(ReorderBuffer));
 
-	memset(&hash_ctl, 0, sizeof(hash_ctl));
+	memset(&hash_ctl, 0, sizeof(HASHCTL));
 
 	buffer->context = new_ctx;
 
@@ -4740,7 +4740,7 @@ ReorderBufferToastReplace(ReorderBuffer *rb, ReorderBufferTXN *txn,
 		else
 			SET_VARSIZE(reconstructed, data_done + VARHDRSZ);
 
-		memset(&redirect_pointer, 0, sizeof(redirect_pointer));
+		memset(&redirect_pointer, 0, sizeof(struct varatt_indirect));
 		redirect_pointer.pointer = reconstructed;
 
 		SET_VARTAG_EXTERNAL(new_datum, VARTAG_INDIRECT);
@@ -5115,7 +5115,7 @@ ResolveCminCmaxDuringDecoding(HTAB *tuplecid_data,
 		return false;
 
 	/* be careful about padding */
-	memset(&key, 0, sizeof(key));
+	memset(&key, 0, sizeof(ReorderBufferTupleCidKey));
 
 	Assert(!BufferIsLocal(buffer));
 
diff --git a/src/backend/storage/ipc/standby.c b/src/backend/storage/ipc/standby.c
index 671b00a33c..42a6f5ee91 100644
--- a/src/backend/storage/ipc/standby.c
+++ b/src/backend/storage/ipc/standby.c
@@ -1402,7 +1402,7 @@ LogStandbyInvalidations(int nmsgs, SharedInvalidationMessage *msgs,
 	xl_invalidations xlrec;
 
 	/* prepare record */
-	memset(&xlrec, 0, sizeof(xlrec));
+	memset(&xlrec, 0, sizeof(xl_invalidations));
 	xlrec.dbId = MyDatabaseId;
 	xlrec.tsId = MyDatabaseTableSpace;
 	xlrec.relcacheInitFileInval = relcacheInitFileInval;
diff --git a/src/backend/storage/lmgr/lock.c b/src/backend/storage/lmgr/lock.c
index 5f5803f681..62f670f5d0 100644
--- a/src/backend/storage/lmgr/lock.c
+++ b/src/backend/storage/lmgr/lock.c
@@ -603,7 +603,7 @@ LockHeldByMe(const LOCKTAG *locktag, LOCKMODE lockmode)
 	/*
 	 * See if there is a LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
+	MemSet(&localtag, 0, sizeof(LOCALLOCKTAG)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
@@ -658,7 +658,7 @@ LockHasWaiters(const LOCKTAG *locktag, LOCKMODE lockmode, bool sessionLock)
 	/*
 	 * Find the LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
+	MemSet(&localtag, 0, sizeof(LOCALLOCKTAG)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
@@ -820,7 +820,7 @@ LockAcquireExtended(const LOCKTAG *locktag,
 	/*
 	 * Find or create a LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
+	MemSet(&localtag, 0, sizeof(LOCALLOCKTAG)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
@@ -1999,7 +1999,7 @@ LockRelease(const LOCKTAG *locktag, LOCKMODE lockmode, bool sessionLock)
 	/*
 	 * Find the LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
+	MemSet(&localtag, 0, sizeof(LOCALLOCKTAG)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
diff --git a/src/backend/storage/lmgr/lwlock.c b/src/backend/storage/lmgr/lwlock.c
index 8aef909037..6b56fc345d 100644
--- a/src/backend/storage/lmgr/lwlock.c
+++ b/src/backend/storage/lmgr/lwlock.c
@@ -397,7 +397,7 @@ get_lwlock_stats_entry(LWLock *lock)
 		return &lwlock_stats_dummy;
 
 	/* Fetch or create the entry. */
-	MemSet(&key, 0, sizeof(key));
+	MemSet(&key, 0, sizeof(lwlock_stats_key));
 	key.tranche = lock->tranche;
 	key.instance = lock;
 	lwstats = hash_search(lwlock_stats_htab, &key, HASH_ENTER, &found);
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index c7ed1e6d7a..f49ee51384 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -320,10 +320,10 @@ pgstat_bestart(void)
 
 	/* These structs can just start from zeroes each time, though */
 #ifdef USE_SSL
-	memset(&lsslstatus, 0, sizeof(lsslstatus));
+	memset(&lsslstatus, 0, sizeof(PgBackendSSLStatus));
 #endif
 #ifdef ENABLE_GSS
-	memset(&lgssstatus, 0, sizeof(lgssstatus));
+	memset(&lgssstatus, 0, sizeof(PgBackendGSSStatus));
 #endif
 
 	/*
@@ -353,9 +353,9 @@ pgstat_bestart(void)
 	 */
 	if (MyProcPort)
 		memcpy(&lbeentry.st_clientaddr, &MyProcPort->raddr,
-			   sizeof(lbeentry.st_clientaddr));
+			   sizeof(SockAddr));
 	else
-		MemSet(&lbeentry.st_clientaddr, 0, sizeof(lbeentry.st_clientaddr));
+		MemSet(&lbeentry.st_clientaddr, 0, sizeof(SockAddr));
 
 #ifdef USE_SSL
 	if (MyProcPort && MyProcPort->ssl_in_use)
diff --git a/src/backend/utils/activity/pgstat_replslot.c b/src/backend/utils/activity/pgstat_replslot.c
index b77c05ab5f..59794eb378 100644
--- a/src/backend/utils/activity/pgstat_replslot.c
+++ b/src/backend/utils/activity/pgstat_replslot.c
@@ -123,7 +123,7 @@ pgstat_create_replslot(ReplicationSlot *slot)
 	 * NB: need to accept that there might be stats from an older slot, e.g.
 	 * if we previously crashed after dropping a slot.
 	 */
-	memset(&shstatent->stats, 0, sizeof(shstatent->stats));
+	memset(&shstatent->stats, 0, sizeof(PgStat_StatReplSlotEntry));
 	namestrcpy(&shstatent->stats.slotname, NameStr(slot->data.name));
 
 	pgstat_unlock_entry(entry_ref);
diff --git a/src/backend/utils/activity/pgstat_wal.c b/src/backend/utils/activity/pgstat_wal.c
index 5a878bd115..993aedf460 100644
--- a/src/backend/utils/activity/pgstat_wal.c
+++ b/src/backend/utils/activity/pgstat_wal.c
@@ -154,7 +154,7 @@ pgstat_wal_reset_all_cb(TimestampTz ts)
 	PgStatShared_Wal *stats_shmem = &pgStatLocal.shmem->wal;
 
 	LWLockAcquire(&stats_shmem->lock, LW_EXCLUSIVE);
-	memset(&stats_shmem->stats, 0, sizeof(stats_shmem->stats));
+	memset(&stats_shmem->stats, 0, sizeof(PgStat_WalStats));
 	stats_shmem->stats.stat_reset_timestamp = ts;
 	LWLockRelease(&stats_shmem->lock);
 }
diff --git a/src/backend/utils/adt/array_selfuncs.c b/src/backend/utils/adt/array_selfuncs.c
index 8cbee1406b..b916d41c20 100644
--- a/src/backend/utils/adt/array_selfuncs.c
+++ b/src/backend/utils/adt/array_selfuncs.c
@@ -151,7 +151,7 @@ scalararraysel_containment(PlannerInfo *root,
 				!get_attstatsslot(&hslot, vardata.statsTuple,
 								  STATISTIC_KIND_DECHIST, InvalidOid,
 								  ATTSTATSSLOT_NUMBERS))
-				memset(&hslot, 0, sizeof(hslot));
+				memset(&hslot, 0, sizeof(AttStatsSlot));
 
 			/*
 			 * For = ANY, estimate as var @> ARRAY[const].
@@ -377,7 +377,7 @@ calc_arraycontsel(VariableStatData *vardata, Datum constval,
 				!get_attstatsslot(&hslot, vardata->statsTuple,
 								  STATISTIC_KIND_DECHIST, InvalidOid,
 								  ATTSTATSSLOT_NUMBERS))
-				memset(&hslot, 0, sizeof(hslot));
+				memset(&hslot, 0, sizeof(AttStatsSlot));
 
 			/* Use the most-common-elements slot for the array Var. */
 			selec = mcelem_array_selec(array, typentry,
diff --git a/src/backend/utils/adt/json.c b/src/backend/utils/adt/json.c
index 553cc25eb9..529c2352b6 100644
--- a/src/backend/utils/adt/json.c
+++ b/src/backend/utils/adt/json.c
@@ -966,7 +966,7 @@ json_unique_check_init(JsonUniqueCheckState *cxt)
 {
 	HASHCTL		ctl;
 
-	memset(&ctl, 0, sizeof(ctl));
+	memset(&ctl, 0, sizeof(HASHCTL));
 	ctl.keysize = sizeof(JsonUniqueHashEntry);
 	ctl.entrysize = sizeof(JsonUniqueHashEntry);
 	ctl.hcxt = CurrentMemoryContext;
@@ -1058,7 +1058,7 @@ json_object_agg_transfn_worker(FunctionCallInfo fcinfo,
 		if (unique_keys)
 			json_unique_builder_init(&state->unique_check);
 		else
-			memset(&state->unique_check, 0, sizeof(state->unique_check));
+			memset(&state->unique_check, 0, sizeof(JsonUniqueBuilderState));
 		MemoryContextSwitchTo(oldcontext);
 
 		arg_type = get_fn_expr_argtype(fcinfo->flinfo, 1);
diff --git a/src/backend/utils/adt/jsonb.c b/src/backend/utils/adt/jsonb.c
index 39355e242d..a09c632c86 100644
--- a/src/backend/utils/adt/jsonb.c
+++ b/src/backend/utils/adt/jsonb.c
@@ -246,8 +246,8 @@ jsonb_from_cstring(char *json, int len, bool unique_keys)
 	JsonbInState state;
 	JsonSemAction sem;
 
-	memset(&state, 0, sizeof(state));
-	memset(&sem, 0, sizeof(sem));
+	memset(&state, 0, sizeof(JsonbInState));
+	memset(&sem, 0, sizeof(JsonSemAction));
 	lex = makeJsonLexContextCstringLen(json, len, GetDatabaseEncoding(), true);
 
 	state.unique_keys = unique_keys;
@@ -839,7 +839,7 @@ datum_to_jsonb(Datum val, bool is_null, JsonbInState *result,
 
 					lex = makeJsonLexContext(json, true);
 
-					memset(&sem, 0, sizeof(sem));
+					memset(&sem, 0, sizeof(JsonSemAction));
 
 					sem.semstate = (void *) result;
 
diff --git a/src/backend/utils/adt/jsonfuncs.c b/src/backend/utils/adt/jsonfuncs.c
index d427bdfbe0..87c6431b33 100644
--- a/src/backend/utils/adt/jsonfuncs.c
+++ b/src/backend/utils/adt/jsonfuncs.c
@@ -2625,7 +2625,7 @@ populate_array_json(PopulateArrayContext *ctx, char *json, int len)
 	state.lex = makeJsonLexContextCstringLen(json, len, GetDatabaseEncoding(), true);
 	state.ctx = ctx;
 
-	memset(&sem, 0, sizeof(sem));
+	memset(&sem, 0, sizeof(JsonSemAction));
 	sem.semstate = (void *) &state;
 	sem.object_start = populate_array_object_start;
 	sem.array_end = populate_array_array_end;
diff --git a/src/backend/utils/adt/mcxtfuncs.c b/src/backend/utils/adt/mcxtfuncs.c
index bb7cc94024..b7f832ccb5 100644
--- a/src/backend/utils/adt/mcxtfuncs.c
+++ b/src/backend/utils/adt/mcxtfuncs.c
@@ -62,7 +62,7 @@ PutMemoryContextsStatsTupleStore(Tuplestorestate *tupstore,
 	}
 
 	/* Examine the context itself */
-	memset(&stat, 0, sizeof(stat));
+	memset(&stat, 0, sizeof(MemoryContextCounters));
 	(*context->methods->stats) (context, NULL, (void *) &level, &stat, true);
 
 	memset(values, 0, sizeof(values));
diff --git a/src/backend/utils/adt/multirangetypes_selfuncs.c b/src/backend/utils/adt/multirangetypes_selfuncs.c
index 919c8889d4..9a74c542ba 100644
--- a/src/backend/utils/adt/multirangetypes_selfuncs.c
+++ b/src/backend/utils/adt/multirangetypes_selfuncs.c
@@ -535,7 +535,7 @@ calc_hist_selectivity(TypeCacheEntry *typcache, VariableStatData *vardata,
 		}
 	}
 	else
-		memset(&lslot, 0, sizeof(lslot));
+		memset(&lslot, 0, sizeof(AttStatsSlot));
 
 	/* Extract the bounds of the constant value. */
 	Assert(constval->rangeCount > 0);
diff --git a/src/backend/utils/adt/network_selfuncs.c b/src/backend/utils/adt/network_selfuncs.c
index 49196376a8..a34e74d97e 100644
--- a/src/backend/utils/adt/network_selfuncs.c
+++ b/src/backend/utils/adt/network_selfuncs.c
@@ -299,8 +299,8 @@ networkjoinsel_inner(Oid operator,
 	}
 	else
 	{
-		memset(&mcv1_slot, 0, sizeof(mcv1_slot));
-		memset(&hist1_slot, 0, sizeof(hist1_slot));
+		memset(&mcv1_slot, 0, sizeof(AttStatsSlot));
+		memset(&hist1_slot, 0, sizeof(AttStatsSlot));
 	}
 
 	if (HeapTupleIsValid(vardata2->statsTuple))
@@ -321,8 +321,8 @@ networkjoinsel_inner(Oid operator,
 	}
 	else
 	{
-		memset(&mcv2_slot, 0, sizeof(mcv2_slot));
-		memset(&hist2_slot, 0, sizeof(hist2_slot));
+		memset(&mcv2_slot, 0, sizeof(AttStatsSlot));
+		memset(&hist2_slot, 0, sizeof(AttStatsSlot));
 	}
 
 	opr_codenum = inet_opr_codenum(operator);
@@ -429,8 +429,8 @@ networkjoinsel_semi(Oid operator,
 	}
 	else
 	{
-		memset(&mcv1_slot, 0, sizeof(mcv1_slot));
-		memset(&hist1_slot, 0, sizeof(hist1_slot));
+		memset(&mcv1_slot, 0, sizeof(AttStatsSlot));
+		memset(&hist1_slot, 0, sizeof(AttStatsSlot));
 	}
 
 	if (HeapTupleIsValid(vardata2->statsTuple))
@@ -451,8 +451,8 @@ networkjoinsel_semi(Oid operator,
 	}
 	else
 	{
-		memset(&mcv2_slot, 0, sizeof(mcv2_slot));
-		memset(&hist2_slot, 0, sizeof(hist2_slot));
+		memset(&mcv2_slot, 0, sizeof(AttStatsSlot));
+		memset(&hist2_slot, 0, sizeof(AttStatsSlot));
 	}
 
 	opr_codenum = inet_opr_codenum(operator);
diff --git a/src/backend/utils/adt/pg_locale.c b/src/backend/utils/adt/pg_locale.c
index a0490a7522..5262b47902 100644
--- a/src/backend/utils/adt/pg_locale.c
+++ b/src/backend/utils/adt/pg_locale.c
@@ -497,7 +497,7 @@ PGLC_localeconv(void)
 	 * allocated with strdup, to avoid premature elog(ERROR) and to allow
 	 * using a single cleanup routine.
 	 */
-	memset(&worklconv, 0, sizeof(worklconv));
+	memset(&worklconv, 0, sizeof(struct lconv));
 
 	/* Save prevailing values of monetary and numeric locales */
 	save_lc_monetary = setlocale(LC_MONETARY, NULL);
@@ -1548,7 +1548,7 @@ pg_newlocale_from_collation(Oid collid)
 		collform = (Form_pg_collation) GETSTRUCT(tp);
 
 		/* We'll fill in the result struct locally before allocating memory */
-		memset(&result, 0, sizeof(result));
+		memset(&result, 0, sizeof(struct pg_locale_struct));
 		result.provider = collform->collprovider;
 		result.deterministic = collform->collisdeterministic;
 
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 893690dad5..1828c2e0fe 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -731,7 +731,7 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 				nulls[11] = true;
 
 			/* A zeroed client addr means we don't know */
-			memset(&zero_clientaddr, 0, sizeof(zero_clientaddr));
+			memset(&zero_clientaddr, 0, sizeof(SockAddr));
 			if (memcmp(&(beentry->st_clientaddr), &zero_clientaddr,
 					   sizeof(zero_clientaddr)) == 0)
 			{
@@ -1103,7 +1103,7 @@ pg_stat_get_backend_client_addr(PG_FUNCTION_ARGS)
 		PG_RETURN_NULL();
 
 	/* A zeroed client addr means we don't know */
-	memset(&zero_clientaddr, 0, sizeof(zero_clientaddr));
+	memset(&zero_clientaddr, 0, sizeof(SockAddr));
 	if (memcmp(&(beentry->st_clientaddr), &zero_clientaddr,
 			   sizeof(zero_clientaddr)) == 0)
 		PG_RETURN_NULL();
@@ -1150,7 +1150,7 @@ pg_stat_get_backend_client_port(PG_FUNCTION_ARGS)
 		PG_RETURN_NULL();
 
 	/* A zeroed client addr means we don't know */
-	memset(&zero_clientaddr, 0, sizeof(zero_clientaddr));
+	memset(&zero_clientaddr, 0, sizeof(SockAddr));
 	if (memcmp(&(beentry->st_clientaddr), &zero_clientaddr,
 			   sizeof(zero_clientaddr)) == 0)
 		PG_RETURN_NULL();
diff --git a/src/backend/utils/adt/rangetypes_selfuncs.c b/src/backend/utils/adt/rangetypes_selfuncs.c
index c2795f4593..9222381181 100644
--- a/src/backend/utils/adt/rangetypes_selfuncs.c
+++ b/src/backend/utils/adt/rangetypes_selfuncs.c
@@ -446,7 +446,7 @@ calc_hist_selectivity(TypeCacheEntry *typcache, VariableStatData *vardata,
 		}
 	}
 	else
-		memset(&lslot, 0, sizeof(lslot));
+		memset(&lslot, 0, sizeof(AttStatsSlot));
 
 	/* Extract the bounds of the constant value. */
 	range_deserialize(typcache, constval, &const_lower, &const_upper, &empty);
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 49c4201dde..50fb6542ec 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -1057,7 +1057,7 @@ pg_get_triggerdef_worker(Oid trigid, bool pretty)
 		newrte->inFromCl = true;
 
 		/* Build two-element rtable */
-		memset(&dpns, 0, sizeof(dpns));
+		memset(&dpns, 0, sizeof(deparse_namespace));
 		dpns.rtable = list_make2(oldrte, newrte);
 		dpns.subplans = NIL;
 		dpns.ctes = NIL;
@@ -3804,7 +3804,7 @@ select_rtable_names_for_explain(List *rtable, Bitmapset *rels_used)
 {
 	deparse_namespace dpns;
 
-	memset(&dpns, 0, sizeof(dpns));
+	memset(&dpns, 0, sizeof(deparse_namespace));
 	dpns.rtable = rtable;
 	dpns.subplans = NIL;
 	dpns.ctes = NIL;
diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c
index fa1f589fad..0dec93f440 100644
--- a/src/backend/utils/adt/selfuncs.c
+++ b/src/backend/utils/adt/selfuncs.c
@@ -2271,8 +2271,8 @@ eqjoinsel(PG_FUNCTION_ARGS)
 
 	opfuncoid = get_opcode(operator);
 
-	memset(&sslot1, 0, sizeof(sslot1));
-	memset(&sslot2, 0, sizeof(sslot2));
+	memset(&sslot1, 0, sizeof(AttStatsSlot));
+	memset(&sslot2, 0, sizeof(AttStatsSlot));
 
 	if (HeapTupleIsValid(vardata1.statsTuple))
 	{
@@ -6797,7 +6797,7 @@ btcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	/*
 	 * Now do generic index cost estimation.
 	 */
-	MemSet(&costs, 0, sizeof(costs));
+	MemSet(&costs, 0, sizeof(GenericCosts));
 	costs.numIndexTuples = numIndexTuples;
 
 	genericcostestimate(root, path, loop_count, &costs);
@@ -6842,7 +6842,7 @@ btcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	 * ordering, but don't negate it entirely.  Before 8.0 we divided the
 	 * correlation by the number of columns, but that seems too strong.)
 	 */
-	MemSet(&vardata, 0, sizeof(vardata));
+	MemSet(&vardata, 0, sizeof(VariableStatData));
 
 	if (index->indexkeys[0] != 0)
 	{
@@ -6949,7 +6949,7 @@ hashcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 {
 	GenericCosts costs;
 
-	MemSet(&costs, 0, sizeof(costs));
+	MemSet(&costs, 0, sizeof(GenericCosts));
 
 	genericcostestimate(root, path, loop_count, &costs);
 
@@ -6995,7 +6995,7 @@ gistcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	GenericCosts costs;
 	Cost		descentCost;
 
-	MemSet(&costs, 0, sizeof(costs));
+	MemSet(&costs, 0, sizeof(GenericCosts));
 
 	genericcostestimate(root, path, loop_count, &costs);
 
@@ -7052,7 +7052,7 @@ spgcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	GenericCosts costs;
 	Cost		descentCost;
 
-	MemSet(&costs, 0, sizeof(costs));
+	MemSet(&costs, 0, sizeof(GenericCosts));
 
 	genericcostestimate(root, path, loop_count, &costs);
 
@@ -7339,7 +7339,7 @@ gincost_scalararrayopexpr(PlannerInfo *root,
 					  elmlen, elmbyval, elmalign,
 					  &elemValues, &elemNulls, &numElems);
 
-	memset(&arraycounts, 0, sizeof(arraycounts));
+	memset(&arraycounts, 0, sizeof(GinQualCounts));
 
 	for (i = 0; i < numElems; i++)
 	{
@@ -7350,7 +7350,7 @@ gincost_scalararrayopexpr(PlannerInfo *root,
 			continue;
 
 		/* Otherwise, apply extractQuery and get the actual term counts */
-		memset(&elemcounts, 0, sizeof(elemcounts));
+		memset(&elemcounts, 0, sizeof(GinQualCounts));
 
 		if (gincost_pattern(index, indexcol, clause_op, elemValues[i],
 							&elemcounts))
@@ -7443,7 +7443,7 @@ gincostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	}
 	else
 	{
-		memset(&ginStats, 0, sizeof(ginStats));
+		memset(&ginStats, 0, sizeof(GinStatsData));
 	}
 
 	/*
@@ -7532,7 +7532,7 @@ gincostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	/*
 	 * Examine quals to estimate number of search entries & partial matches
 	 */
-	memset(&counts, 0, sizeof(counts));
+	memset(&counts, 0, sizeof(GinQualCounts));
 	counts.arrayScans = 1;
 	matchPossible = true;
 
diff --git a/src/backend/utils/adt/tsvector_op.c b/src/backend/utils/adt/tsvector_op.c
index addc349151..9394a02ba2 100644
--- a/src/backend/utils/adt/tsvector_op.c
+++ b/src/backend/utils/adt/tsvector_op.c
@@ -1671,8 +1671,8 @@ TS_phrase_execute(QueryItem *curitem, void *arg, uint32 flags,
 
 		case OP_PHRASE:
 		case OP_AND:
-			memset(&Ldata, 0, sizeof(Ldata));
-			memset(&Rdata, 0, sizeof(Rdata));
+			memset(&Ldata, 0, sizeof(ExecPhraseData));
+			memset(&Rdata, 0, sizeof(ExecPhraseData));
 
 			lmatch = TS_phrase_execute(curitem + curitem->qoperator.left,
 									   arg, flags, chkcond, &Ldata);
@@ -1753,8 +1753,8 @@ TS_phrase_execute(QueryItem *curitem, void *arg, uint32 flags,
 			}
 
 		case OP_OR:
-			memset(&Ldata, 0, sizeof(Ldata));
-			memset(&Rdata, 0, sizeof(Rdata));
+			memset(&Ldata, 0, sizeof(ExecPhraseData));
+			memset(&Rdata, 0, sizeof(ExecPhraseData));
 
 			lmatch = TS_phrase_execute(curitem + curitem->qoperator.left,
 									   arg, flags, chkcond, &Ldata);
diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c
index 919138eaf3..40d4bbb48a 100644
--- a/src/backend/utils/adt/varlena.c
+++ b/src/backend/utils/adt/varlena.c
@@ -4775,7 +4775,7 @@ text_to_array(PG_FUNCTION_ARGS)
 	SplitTextOutputData tstate;
 
 	/* For array output, tstate should start as all zeroes */
-	memset(&tstate, 0, sizeof(tstate));
+	memset(&tstate, 0, sizeof(SplitTextOutputData));
 
 	if (!split_text(fcinfo, &tstate))
 		PG_RETURN_NULL();
diff --git a/src/backend/utils/cache/attoptcache.c b/src/backend/utils/cache/attoptcache.c
index 9e252a0891..ce4c66962f 100644
--- a/src/backend/utils/cache/attoptcache.c
+++ b/src/backend/utils/cache/attoptcache.c
@@ -110,7 +110,7 @@ get_attribute_options(Oid attrelid, int attnum)
 	/* Find existing cache entry, if any. */
 	if (!AttoptCacheHash)
 		InitializeAttoptCache();
-	memset(&key, 0, sizeof(key));	/* make sure any padding bits are unset */
+	memset(&key, 0, sizeof(AttoptCacheKey));	/* make sure any padding bits are unset */
 	key.attrelid = attrelid;
 	key.attnum = attnum;
 	attopt =
diff --git a/src/backend/utils/cache/relfilenodemap.c b/src/backend/utils/cache/relfilenodemap.c
index 70c323c720..266d9aef5e 100644
--- a/src/backend/utils/cache/relfilenodemap.c
+++ b/src/backend/utils/cache/relfilenodemap.c
@@ -153,7 +153,7 @@ RelidByRelfilenode(Oid reltablespace, Oid relfilenode)
 	if (reltablespace == MyDatabaseTableSpace)
 		reltablespace = 0;
 
-	MemSet(&key, 0, sizeof(key));
+	MemSet(&key, 0, sizeof(RelfilenodeMapKey));
 	key.reltablespace = reltablespace;
 	key.relfilenode = relfilenode;
 
diff --git a/src/backend/utils/fmgr/funcapi.c b/src/backend/utils/fmgr/funcapi.c
index 9197b0f1e2..6c49d4f948 100644
--- a/src/backend/utils/fmgr/funcapi.c
+++ b/src/backend/utils/fmgr/funcapi.c
@@ -776,8 +776,8 @@ resolve_polymorphic_tupdesc(TupleDesc tupdesc, oidvector *declared_args,
 	if (!call_expr)
 		return false;			/* no hope */
 
-	memset(&poly_actuals, 0, sizeof(poly_actuals));
-	memset(&anyc_actuals, 0, sizeof(anyc_actuals));
+	memset(&poly_actuals, 0, sizeof(polymorphic_actuals));
+	memset(&anyc_actuals, 0, sizeof(polymorphic_actuals));
 
 	for (i = 0; i < nargs; i++)
 	{
@@ -1041,8 +1041,8 @@ resolve_polymorphic_argtypes(int numargs, Oid *argtypes, char *argmodes,
 	 * resolve_polymorphic_tupdesc, we rely on the parser to have enforced
 	 * type consistency and coerced ANYCOMPATIBLE args to a common supertype.
 	 */
-	memset(&poly_actuals, 0, sizeof(poly_actuals));
-	memset(&anyc_actuals, 0, sizeof(anyc_actuals));
+	memset(&poly_actuals, 0, sizeof(polymorphic_actuals));
+	memset(&anyc_actuals, 0, sizeof(polymorphic_actuals));
 	inargno = 0;
 	for (i = 0; i < numargs; i++)
 	{
diff --git a/src/backend/utils/mmgr/mcxt.c b/src/backend/utils/mmgr/mcxt.c
index e12be1b9bd..76ec50e5dc 100644
--- a/src/backend/utils/mmgr/mcxt.c
+++ b/src/backend/utils/mmgr/mcxt.c
@@ -522,7 +522,7 @@ MemoryContextStatsDetail(MemoryContext context, int max_children,
 {
 	MemoryContextCounters grand_totals;
 
-	memset(&grand_totals, 0, sizeof(grand_totals));
+	memset(&grand_totals, 0, sizeof(MemoryContextCounters));
 
 	MemoryContextStatsInternal(context, 0, true, max_children, &grand_totals, print_to_stderr);
 
@@ -582,7 +582,7 @@ MemoryContextStatsInternal(MemoryContext context, int level,
 	 * Examine children.  If there are more than max_children of them, we do
 	 * not print the rest explicitly, but just summarize them.
 	 */
-	memset(&local_totals, 0, sizeof(local_totals));
+	memset(&local_totals, 0, sizeof(MemoryContextCounters));
 
 	for (child = context->firstchild, ichild = 0;
 		 child != NULL;
diff --git a/src/backend/utils/time/snapmgr.c b/src/backend/utils/time/snapmgr.c
index 5bc2a15160..84aecf64ec 100644
--- a/src/backend/utils/time/snapmgr.c
+++ b/src/backend/utils/time/snapmgr.c
@@ -1462,7 +1462,7 @@ ImportSnapshot(const char *idstr)
 	/*
 	 * Construct a snapshot struct by parsing the file content.
 	 */
-	memset(&snapshot, 0, sizeof(snapshot));
+	memset(&snapshot, 0, sizeof(SnapshotData));
 
 	parseVxidFromText("vxid:", &filebuf, path, &src_vxid);
 	src_pid = parseIntFromText("pid:", &filebuf, path);
diff --git a/src/bin/initdb/findtimezone.c b/src/bin/initdb/findtimezone.c
index ddb65e6489..7ff01ffef6 100644
--- a/src/bin/initdb/findtimezone.c
+++ b/src/bin/initdb/findtimezone.c
@@ -191,7 +191,7 @@ build_time_t(int year, int month, int day)
 {
 	struct tm	tm;
 
-	memset(&tm, 0, sizeof(tm));
+	memset(&tm, 0, sizeof(struct tm));
 	tm.tm_mday = day;
 	tm.tm_mon = month - 1;
 	tm.tm_year = year - 1900;
diff --git a/src/bin/initdb/initdb.c b/src/bin/initdb/initdb.c
index ed6de7ca94..547efef1df 100644
--- a/src/bin/initdb/initdb.c
+++ b/src/bin/initdb/initdb.c
@@ -1959,7 +1959,7 @@ locale_date_order(const char *locale)
 
 	setlocale(LC_TIME, locale);
 
-	memset(&testtime, 0, sizeof(testtime));
+	memset(&testtime, 0, sizeof(struct tm));
 	testtime.tm_mday = 22;
 	testtime.tm_mon = 10;		/* November, should come out as "11" */
 	testtime.tm_year = 133;		/* 2033 */
diff --git a/src/bin/pg_basebackup/pg_basebackup.c b/src/bin/pg_basebackup/pg_basebackup.c
index 4adb170d46..56aed21433 100644
--- a/src/bin/pg_basebackup/pg_basebackup.c
+++ b/src/bin/pg_basebackup/pg_basebackup.c
@@ -457,7 +457,7 @@ reached_end_position(XLogRecPtr segendpos, uint32 timeline,
 		FD_ZERO(&fds);
 		FD_SET(bgpipe[0], &fds);
 
-		MemSet(&tv, 0, sizeof(tv));
+		MemSet(&tv, 0, sizeof(struct timeval));
 
 		r = select(bgpipe[0] + 1, &fds, NULL, NULL, &tv);
 		if (r == 1)
@@ -532,7 +532,7 @@ LogStreamerMain(logstreamer_param *param)
 
 	in_log_streamer = true;
 
-	MemSet(&stream, 0, sizeof(stream));
+	MemSet(&stream, 0, sizeof(StreamCtl));
 	stream.startpos = param->startptr;
 	stream.timeline = param->timeline;
 	stream.sysidentifier = param->sysidentifier;
@@ -1293,7 +1293,7 @@ ReceiveArchiveStream(PGconn *conn, pg_compress_specification *compress)
 	ArchiveStreamState state;
 
 	/* Set up initial state. */
-	memset(&state, 0, sizeof(state));
+	memset(&state, 0, sizeof(ArchiveStreamState));
 	state.tablespacenum = -1;
 	state.compress = compress;
 
@@ -1612,7 +1612,7 @@ ReceiveTarFile(PGconn *conn, char *archive_name, char *spclocation,
 	bool		expect_unterminated_tarfile;
 
 	/* Pass all COPY data through to the backup streamer. */
-	memset(&state, 0, sizeof(state));
+	memset(&state, 0, sizeof(WriteTarState));
 	is_recovery_guc_supported =
 		PQserverVersion(conn) >= MINIMUM_VERSION_FOR_RECOVERY_GUC;
 	expect_unterminated_tarfile =
diff --git a/src/bin/pg_basebackup/pg_receivewal.c b/src/bin/pg_basebackup/pg_receivewal.c
index ea3902c971..7c19e2ee24 100644
--- a/src/bin/pg_basebackup/pg_receivewal.c
+++ b/src/bin/pg_basebackup/pg_receivewal.c
@@ -439,7 +439,7 @@ FindStreamingStart(uint32 *tli)
 			LZ4F_decompressOptions_t dec_opt;
 			LZ4F_errorCode_t status;
 
-			memset(&dec_opt, 0, sizeof(dec_opt));
+			memset(&dec_opt, 0, sizeof(LZ4F_decompressOptions_t));
 			snprintf(fullpath, sizeof(fullpath), "%s/%s", basedir, dirent->d_name);
 
 			fd = open(fullpath, O_RDONLY | PG_BINARY, 0);
@@ -567,7 +567,7 @@ StreamLog(void)
 	StreamCtl	stream;
 	char	   *sysidentifier;
 
-	MemSet(&stream, 0, sizeof(stream));
+	MemSet(&stream, 0, sizeof(StreamCtl));
 
 	/*
 	 * Connect in replication mode to the server
diff --git a/src/bin/pg_basebackup/walmethods.c b/src/bin/pg_basebackup/walmethods.c
index cc292718da..6c119a6757 100644
--- a/src/bin/pg_basebackup/walmethods.c
+++ b/src/bin/pg_basebackup/walmethods.c
@@ -179,7 +179,7 @@ dir_open_for_write(const char *pathname, const char *temp_suffix, size_t pad_to_
 		lz4buf = pg_malloc0(lz4bufsize);
 
 		/* assign the compression level, default is 0 */
-		memset(&prefs, 0, sizeof(prefs));
+		memset(&prefs, 0, sizeof(LZ4F_preferences_t));
 		prefs.compressionLevel = dir_data->compression_level;
 
 		/* add the header */
diff --git a/src/bin/pg_ctl/pg_ctl.c b/src/bin/pg_ctl/pg_ctl.c
index dd78e5bc66..6e31fabb8d 100644
--- a/src/bin/pg_ctl/pg_ctl.c
+++ b/src/bin/pg_ctl/pg_ctl.c
@@ -1632,7 +1632,7 @@ pgwin32_ServiceMain(DWORD argc, LPTSTR *argv)
 	status.dwServiceSpecificExitCode = 0;
 	status.dwCurrentState = SERVICE_START_PENDING;
 
-	memset(&pi, 0, sizeof(pi));
+	memset(&pi, 0, sizeof(PROCESS_INFORMATION));
 
 	read_post_opts();
 
diff --git a/src/bin/pg_verifybackup/pg_verifybackup.c b/src/bin/pg_verifybackup/pg_verifybackup.c
index bd18b4491d..9bb61ba6a2 100644
--- a/src/bin/pg_verifybackup/pg_verifybackup.c
+++ b/src/bin/pg_verifybackup/pg_verifybackup.c
@@ -182,7 +182,7 @@ main(int argc, char **argv)
 	set_pglocale_pgservice(argv[0], PG_TEXTDOMAIN("pg_verifybackup"));
 	progname = get_progname(argv[0]);
 
-	memset(&context, 0, sizeof(context));
+	memset(&context, 0, sizeof(verifier_context));
 
 	if (argc > 1)
 	{
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index b51d28780b..00a44e3589 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -5172,7 +5172,7 @@ do_watch(PQExpBuffer query_buf, double sleep)
 
 #ifdef HAVE_POSIX_DECL_SIGWAIT
 	/* Disable the interval timer. */
-	memset(&interval, 0, sizeof(interval));
+	memset(&interval, 0, sizeof(struct itimerval));
 	setitimer(ITIMER_REAL, &interval, NULL);
 	/* Unblock SIGINT, SIGCHLD and SIGALRM. */
 	sigprocmask(SIG_UNBLOCK, &sigalrm_sigchld_sigint, NULL);
diff --git a/src/bin/scripts/vacuumdb.c b/src/bin/scripts/vacuumdb.c
index 92f1ffe147..b444256482 100644
--- a/src/bin/scripts/vacuumdb.c
+++ b/src/bin/scripts/vacuumdb.c
@@ -127,7 +127,7 @@ main(int argc, char *argv[])
 	int			tbl_count = 0;
 
 	/* initialize options */
-	memset(&vacopts, 0, sizeof(vacopts));
+	memset(&vacopts, 0, sizeof(vacuumingOptions));
 	vacopts.parallel_workers = -1;
 	vacopts.no_index_cleanup = false;
 	vacopts.force_index_cleanup = false;
diff --git a/src/common/ip.c b/src/common/ip.c
index cd73d49679..771d752a8a 100644
--- a/src/common/ip.c
+++ b/src/common/ip.c
@@ -171,7 +171,7 @@ getaddrinfo_unix(const char *path, const struct addrinfo *hintsp,
 
 	*result = NULL;
 
-	MemSet(&hints, 0, sizeof(hints));
+	MemSet(&hints, 0, sizeof(struct addrinfo));
 
 	if (strlen(path) >= sizeof(unp->sun_path))
 		return EAI_FAIL;
@@ -182,7 +182,7 @@ getaddrinfo_unix(const char *path, const struct addrinfo *hintsp,
 		hints.ai_socktype = SOCK_STREAM;
 	}
 	else
-		memcpy(&hints, hintsp, sizeof(hints));
+		memcpy(&hints, hintsp, sizeof(struct addrinfo));
 
 	if (hints.ai_socktype == 0)
 		hints.ai_socktype = SOCK_STREAM;
diff --git a/src/interfaces/libpq/fe-auth.c b/src/interfaces/libpq/fe-auth.c
index 0a072a36dc..9c96c94d4a 100644
--- a/src/interfaces/libpq/fe-auth.c
+++ b/src/interfaces/libpq/fe-auth.c
@@ -737,12 +737,12 @@ pg_local_sendauth(PGconn *conn)
 	iov.iov_base = &buf;
 	iov.iov_len = 1;
 
-	memset(&msg, 0, sizeof(msg));
+	memset(&msg, 0, sizeof(struct msghdr));
 	msg.msg_iov = &iov;
 	msg.msg_iovlen = 1;
 
 	/* We must set up a message that will be filled in by kernel */
-	memset(&cmsgbuf, 0, sizeof(cmsgbuf));
+	memset(&cmsgbuf, 0, sizeof(struct cmsghdr));
 	msg.msg_control = &cmsgbuf.buf;
 	msg.msg_controllen = sizeof(cmsgbuf.buf);
 	cmsg = CMSG_FIRSTHDR(&msg);
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 6e936bbff3..bb70a90d5e 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -2378,7 +2378,7 @@ keep_going:						/* We will come back to here until there is
 		ch = &conn->connhost[conn->whichhost];
 
 		/* Initialize hint structure */
-		MemSet(&hint, 0, sizeof(hint));
+		MemSet(&hint, 0, sizeof(struct addrinfo));
 		hint.ai_socktype = SOCK_STREAM;
 		conn->addrlist_family = hint.ai_family = AF_UNSPEC;
 
diff --git a/src/pl/plperl/plperl.c b/src/pl/plperl/plperl.c
index edb93ec1c4..c7c7930951 100644
--- a/src/pl/plperl/plperl.c
+++ b/src/pl/plperl/plperl.c
@@ -1844,7 +1844,7 @@ plperl_call_handler(PG_FUNCTION_ARGS)
 	plperl_call_data this_call_data;
 
 	/* Initialize current-call status record */
-	MemSet(&this_call_data, 0, sizeof(this_call_data));
+	MemSet(&this_call_data, 0, sizeof(plperl_call_data));
 	this_call_data.fcinfo = fcinfo;
 
 	PG_TRY();
@@ -1890,7 +1890,7 @@ plperl_inline_handler(PG_FUNCTION_ARGS)
 	ErrorContextCallback pl_error_context;
 
 	/* Initialize current-call status record */
-	MemSet(&this_call_data, 0, sizeof(this_call_data));
+	MemSet(&this_call_data, 0, sizeof(plperl_call_data));
 
 	/* Set up a callback for error reporting */
 	pl_error_context.callback = plperl_inline_callback;
@@ -1904,8 +1904,8 @@ plperl_inline_handler(PG_FUNCTION_ARGS)
 	 * with no arguments passed, and a result type of VOID.
 	 */
 	MemSet(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
-	MemSet(&flinfo, 0, sizeof(flinfo));
-	MemSet(&desc, 0, sizeof(desc));
+	MemSet(&flinfo, 0, sizeof(FmgrInfo));
+	MemSet(&desc, 0, sizeof(plperl_proc_desc));
 	fake_fcinfo->flinfo = &flinfo;
 	flinfo.fn_oid = InvalidOid;
 	flinfo.fn_mcxt = CurrentMemoryContext;
diff --git a/src/pl/plpgsql/src/pl_handler.c b/src/pl/plpgsql/src/pl_handler.c
index 190d286f1c..2b58c3202c 100644
--- a/src/pl/plpgsql/src/pl_handler.c
+++ b/src/pl/plpgsql/src/pl_handler.c
@@ -341,7 +341,7 @@ plpgsql_inline_handler(PG_FUNCTION_ARGS)
 	 * with no arguments passed.
 	 */
 	MemSet(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
-	MemSet(&flinfo, 0, sizeof(flinfo));
+	MemSet(&flinfo, 0, sizeof(FmgrInfo));
 	fake_fcinfo->flinfo = &flinfo;
 	flinfo.fn_oid = InvalidOid;
 	flinfo.fn_mcxt = CurrentMemoryContext;
@@ -518,19 +518,19 @@ plpgsql_validator(PG_FUNCTION_ARGS)
 		 * plpgsql_compile().
 		 */
 		MemSet(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
-		MemSet(&flinfo, 0, sizeof(flinfo));
+		MemSet(&flinfo, 0, sizeof(FmgrInfo));
 		fake_fcinfo->flinfo = &flinfo;
 		flinfo.fn_oid = funcoid;
 		flinfo.fn_mcxt = CurrentMemoryContext;
 		if (is_dml_trigger)
 		{
-			MemSet(&trigdata, 0, sizeof(trigdata));
+			MemSet(&trigdata, 0, sizeof(TriggerData));
 			trigdata.type = T_TriggerData;
 			fake_fcinfo->context = (Node *) &trigdata;
 		}
 		else if (is_event_trigger)
 		{
-			MemSet(&etrigdata, 0, sizeof(etrigdata));
+			MemSet(&etrigdata, 0, sizeof(EventTriggerData));
 			etrigdata.type = T_EventTriggerData;
 			fake_fcinfo->context = (Node *) &etrigdata;
 		}
diff --git a/src/pl/plpython/plpy_main.c b/src/pl/plpython/plpy_main.c
index 0bce106495..0d84d66684 100644
--- a/src/pl/plpython/plpy_main.c
+++ b/src/pl/plpython/plpy_main.c
@@ -278,7 +278,7 @@ plpython3_inline_handler(PG_FUNCTION_ARGS)
 		elog(ERROR, "SPI_connect failed");
 
 	MemSet(fcinfo, 0, SizeForFunctionCallInfo(0));
-	MemSet(&flinfo, 0, sizeof(flinfo));
+	MemSet(&flinfo, 0, sizeof(FmgrInfo));
 	fake_fcinfo->flinfo = &flinfo;
 	flinfo.fn_oid = InvalidOid;
 	flinfo.fn_mcxt = CurrentMemoryContext;
diff --git a/src/port/getaddrinfo.c b/src/port/getaddrinfo.c
index 3284c6eb52..818fc6151d 100644
--- a/src/port/getaddrinfo.c
+++ b/src/port/getaddrinfo.c
@@ -146,12 +146,12 @@ getaddrinfo(const char *node, const char *service,
 
 	if (hintp == NULL)
 	{
-		memset(&hints, 0, sizeof(hints));
+		memset(&hints, 0, sizeof(struct addrinfo));
 		hints.ai_family = AF_INET;
 		hints.ai_socktype = SOCK_STREAM;
 	}
 	else
-		memcpy(&hints, hintp, sizeof(hints));
+		memcpy(&hints, hintp, sizeof(struct addrinfo));
 
 	if (hints.ai_family != AF_INET && hints.ai_family != AF_UNSPEC)
 		return EAI_FAMILY;
@@ -162,7 +162,7 @@ getaddrinfo(const char *node, const char *service,
 	if (!node && !service)
 		return EAI_NONAME;
 
-	memset(&sin, 0, sizeof(sin));
+	memset(&sin, 0, sizeof(struct sockaddr_in));
 
 	sin.sin_family = AF_INET;
 
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 12179f2514..c409694539 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -1121,7 +1121,7 @@ printResultSet(PGresult *res)
 {
 	PQprintOpt	popt;
 
-	memset(&popt, 0, sizeof(popt));
+	memset(&popt, 0, sizeof(PQprintOpt));
 	popt.header = true;
 	popt.align = true;
 	popt.fieldSep = "|";
diff --git a/src/test/modules/test_shm_mq/setup.c b/src/test/modules/test_shm_mq/setup.c
index 6f1f4cf9c6..6a0e40db8e 100644
--- a/src/test/modules/test_shm_mq/setup.c
+++ b/src/test/modules/test_shm_mq/setup.c
@@ -212,7 +212,7 @@ setup_background_workers(int nworkers, dsm_segment *seg)
 				  PointerGetDatum(wstate));
 
 	/* Configure a worker. */
-	memset(&worker, 0, sizeof(worker));
+	memset(&worker, 0, sizeof(BackgroundWorker));
 	worker.bgw_flags = BGWORKER_SHMEM_ACCESS;
 	worker.bgw_start_time = BgWorkerStart_ConsistentState;
 	worker.bgw_restart_time = BGW_NEVER_RESTART;
diff --git a/src/test/modules/worker_spi/worker_spi.c b/src/test/modules/worker_spi/worker_spi.c
index 5b541ec47f..13c6afa694 100644
--- a/src/test/modules/worker_spi/worker_spi.c
+++ b/src/test/modules/worker_spi/worker_spi.c
@@ -325,7 +325,7 @@ _PG_init(void)
 	MarkGUCPrefixReserved("worker_spi");
 
 	/* set up common data for all our workers */
-	memset(&worker, 0, sizeof(worker));
+	memset(&worker, 0, sizeof(BackgroundWorker));
 	worker.bgw_flags = BGWORKER_SHMEM_ACCESS |
 		BGWORKER_BACKEND_DATABASE_CONNECTION;
 	worker.bgw_start_time = BgWorkerStart_RecoveryFinished;
@@ -359,7 +359,7 @@ worker_spi_launch(PG_FUNCTION_ARGS)
 	BgwHandleStatus status;
 	pid_t		pid;
 
-	memset(&worker, 0, sizeof(worker));
+	memset(&worker, 0, sizeof(BackgroundWorker));
 	worker.bgw_flags = BGWORKER_SHMEM_ACCESS |
 		BGWORKER_BACKEND_DATABASE_CONNECTION;
 	worker.bgw_start_time = BgWorkerStart_RecoveryFinished;
diff --git a/src/test/regress/pg_regress.c b/src/test/regress/pg_regress.c
index 982801e029..66e8eae77c 100644
--- a/src/test/regress/pg_regress.c
+++ b/src/test/regress/pg_regress.c
@@ -1125,7 +1125,7 @@ spawn_process(const char *cmdline)
 	if (comspec == NULL)
 		comspec = "CMD";
 
-	memset(&pi, 0, sizeof(pi));
+	memset(&pi, 0, sizeof(PROCESS_INFORMATION));
 	cmdline2 = psprintf("\"%s\" /c \"%s\"", comspec, cmdline);
 
 	if ((restrictedToken =
diff --git a/src/tools/msvc/MSBuildProject.pm b/src/tools/msvc/MSBuildProject.pm
index f24d9e5348..5e2a300127 100644
--- a/src/tools/msvc/MSBuildProject.pm
+++ b/src/tools/msvc/MSBuildProject.pm
@@ -331,7 +331,7 @@ sub WriteItemDefinitionGroup
       <ObjectFileName>.\\$cfgname\\$self->{name}\\</ObjectFileName>
       <ProgramDataBaseFileName>.\\$cfgname\\$self->{name}\\</ProgramDataBaseFileName>
       <BrowseInformation>false</BrowseInformation>
-      <WarningLevel>Level3</WarningLevel>
+      <WarningLevel>Level4</WarningLevel>
       <SuppressStartupBanner>true</SuppressStartupBanner>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <CompileAs>Default</CompileAs>

diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index 60e72f9e8b..6da7a5cf7f 100644
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -6265,7 +6265,7 @@ load_relcache_init_file(bool shared)
 		rel->rd_firstRelfilenodeSubid = InvalidSubTransactionId;
 		rel->rd_droppedSubid = InvalidSubTransactionId;
 		rel->rd_amcache = NULL;
-		MemSet(&rel->pgstat_info, 0, sizeof(rel->pgstat_info));
+		rel->pgstat_info = NULL;

diff --git a/contrib/amcheck/verify_heapam.c b/contrib/amcheck/verify_heapam.c
index c875f3e5a2..71defb9cc6 100644
--- a/contrib/amcheck/verify_heapam.c
+++ b/contrib/amcheck/verify_heapam.c
@@ -558,8 +558,8 @@ report_corruption_internal(Tuplestorestate *tupstore, TupleDesc tupdesc,
 	bool		nulls[HEAPCHECK_RELATION_COLS];
 	HeapTuple	tuple;
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(values, 0, sizeof(values));
+	memset(nulls, 0, sizeof(nulls));
 	values[0] = Int64GetDatum(blkno);
 	values[1] = Int32GetDatum(offnum);
 	values[2] = Int32GetDatum(attnum);
diff --git a/contrib/bloom/blcost.c b/contrib/bloom/blcost.c
index d42e4e9628..cf3291375e 100644
--- a/contrib/bloom/blcost.c
+++ b/contrib/bloom/blcost.c
@@ -28,7 +28,7 @@ blcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	IndexOptInfo *index = path->indexinfo;
 	GenericCosts costs;
 
-	MemSet(&costs, 0, sizeof(costs));
+	memset(&costs, 0, sizeof(costs));
 
 	/* We have to visit all index tuples anyway */
 	costs.numIndexTuples = index->tuples;
diff --git a/contrib/hstore/hstore_gist.c b/contrib/hstore/hstore_gist.c
index 102c9cea72..016bfa4a4c 100644
--- a/contrib/hstore/hstore_gist.c
+++ b/contrib/hstore/hstore_gist.c
@@ -459,7 +459,7 @@ ghstore_picksplit(PG_FUNCTION_ARGS)
 			if (ISALLTRUE(datum_l) || ISALLTRUE(_j))
 			{
 				if (!ISALLTRUE(datum_l))
-					MemSet((void *) union_l, 0xff, siglen);
+					memset((void *) union_l, 0xff, siglen);
 			}
 			else
 			{
@@ -475,7 +475,7 @@ ghstore_picksplit(PG_FUNCTION_ARGS)
 			if (ISALLTRUE(datum_r) || ISALLTRUE(_j))
 			{
 				if (!ISALLTRUE(datum_r))
-					MemSet((void *) union_r, 0xff, siglen);
+					memset((void *) union_r, 0xff, siglen);
 			}
 			else
 			{
diff --git a/contrib/hstore/hstore_io.c b/contrib/hstore/hstore_io.c
index b3304ff844..2c871c6d93 100644
--- a/contrib/hstore/hstore_io.c
+++ b/contrib/hstore/hstore_io.c
@@ -841,7 +841,7 @@ hstore_from_record(PG_FUNCTION_ARGS)
 	if (my_extra->record_type != tupType ||
 		my_extra->record_typmod != tupTypmod)
 	{
-		MemSet(my_extra, 0,
+		memset(my_extra, 0,
 			   offsetof(RecordIOData, columns) +
 			   ncolumns * sizeof(ColumnIOData));
 		my_extra->record_type = tupType;
@@ -1035,7 +1035,7 @@ hstore_populate_record(PG_FUNCTION_ARGS)
 	if (my_extra->record_type != tupType ||
 		my_extra->record_typmod != tupTypmod)
 	{
-		MemSet(my_extra, 0,
+		memset(my_extra, 0,
 			   offsetof(RecordIOData, columns) +
 			   ncolumns * sizeof(ColumnIOData));
 		my_extra->record_type = tupType;
diff --git a/contrib/intarray/_intbig_gist.c b/contrib/intarray/_intbig_gist.c
index 18ecd8cda6..c9d8f9b84d 100644
--- a/contrib/intarray/_intbig_gist.c
+++ b/contrib/intarray/_intbig_gist.c
@@ -420,7 +420,7 @@ g_intbig_picksplit(PG_FUNCTION_ARGS)
 			if (ISALLTRUE(datum_l) || ISALLTRUE(_j))
 			{
 				if (!ISALLTRUE(datum_l))
-					MemSet((void *) union_l, 0xff, siglen);
+					memset((void *) union_l, 0xff, siglen);
 			}
 			else
 			{
@@ -436,7 +436,7 @@ g_intbig_picksplit(PG_FUNCTION_ARGS)
 			if (ISALLTRUE(datum_r) || ISALLTRUE(_j))
 			{
 				if (!ISALLTRUE(datum_r))
-					MemSet((void *) union_r, 0xff, siglen);
+					memset((void *) union_r, 0xff, siglen);
 			}
 			else
 			{
diff --git a/contrib/ltree/_ltree_gist.c b/contrib/ltree/_ltree_gist.c
index 72516c3b6b..2dc59f8a0f 100644
--- a/contrib/ltree/_ltree_gist.c
+++ b/contrib/ltree/_ltree_gist.c
@@ -345,7 +345,7 @@ _ltree_picksplit(PG_FUNCTION_ARGS)
 			if (LTG_ISALLTRUE(datum_l) || LTG_ISALLTRUE(_j))
 			{
 				if (!LTG_ISALLTRUE(datum_l))
-					MemSet((void *) union_l, 0xff, siglen);
+					memset((void *) union_l, 0xff, siglen);
 			}
 			else
 			{
@@ -361,7 +361,7 @@ _ltree_picksplit(PG_FUNCTION_ARGS)
 			if (LTG_ISALLTRUE(datum_r) || LTG_ISALLTRUE(_j))
 			{
 				if (!LTG_ISALLTRUE(datum_r))
-					MemSet((void *) union_r, 0xff, siglen);
+					memset((void *) union_r, 0xff, siglen);
 			}
 			else
 			{
diff --git a/contrib/oid2name/oid2name.c b/contrib/oid2name/oid2name.c
index a62a5eedb1..a3e358bb1b 100644
--- a/contrib/oid2name/oid2name.c
+++ b/contrib/oid2name/oid2name.c
@@ -424,7 +424,7 @@ sql_exec(PGconn *conn, const char *todo, bool quiet)
 		}
 		fprintf(stdout, "\n");
 		pad = (char *) pg_malloc(l + 1);
-		MemSet(pad, '-', l);
+		memset(pad, '-', l);
 		pad[l] = '\0';
 		fprintf(stdout, "%s\n", pad);
 		free(pad);
diff --git a/contrib/pageinspect/brinfuncs.c b/contrib/pageinspect/brinfuncs.c
index 879276e6de..b82cb2b5a1 100644
--- a/contrib/pageinspect/brinfuncs.c
+++ b/contrib/pageinspect/brinfuncs.c
@@ -230,7 +230,7 @@ brin_page_items(PG_FUNCTION_ARGS)
 		else
 			attno++;
 
-		MemSet(nulls, 0, sizeof(nulls));
+		memset(nulls, 0, sizeof(nulls));
 
 		if (unusedItem)
 		{
@@ -354,7 +354,7 @@ brin_metapage_info(PG_FUNCTION_ARGS)
 
 	/* Extract values from the metapage */
 	meta = (BrinMetaPageData *) PageGetContents(page);
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(nulls, 0, sizeof(nulls));
 	values[0] = CStringGetTextDatum(psprintf("0x%08X", meta->brinMagic));
 	values[1] = Int32GetDatum(meta->brinVersion);
 	values[2] = Int32GetDatum(meta->pagesPerRange);
diff --git a/contrib/pageinspect/hashfuncs.c b/contrib/pageinspect/hashfuncs.c
index 69af7b962f..4ae6bc0518 100644
--- a/contrib/pageinspect/hashfuncs.c
+++ b/contrib/pageinspect/hashfuncs.c
@@ -261,7 +261,7 @@ hash_page_stats(PG_FUNCTION_ARGS)
 		elog(ERROR, "return type must be a row type");
 	tupleDesc = BlessTupleDesc(tupleDesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(nulls, 0, sizeof(nulls));
 
 	j = 0;
 	values[j++] = Int32GetDatum(stat.live_items);
@@ -361,7 +361,7 @@ hash_page_items(PG_FUNCTION_ARGS)
 
 		itup = (IndexTuple) PageGetItem(uargs->page, id);
 
-		MemSet(nulls, 0, sizeof(nulls));
+		memset(nulls, 0, sizeof(nulls));
 
 		j = 0;
 		values[j++] = Int32GetDatum((int32) uargs->offset);
@@ -495,7 +495,7 @@ hash_bitmap_info(PG_FUNCTION_ARGS)
 		elog(ERROR, "return type must be a row type");
 	tupleDesc = BlessTupleDesc(tupleDesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(nulls, 0, sizeof(nulls));
 
 	j = 0;
 	values[j++] = Int64GetDatum((int64) bitmapblkno);
@@ -544,7 +544,7 @@ hash_metapage_info(PG_FUNCTION_ARGS)
 
 	metad = HashPageGetMeta(page);
 
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(nulls, 0, sizeof(nulls));
 
 	j = 0;
 	values[j++] = Int64GetDatum((int64) metad->hashm_magic);
diff --git a/contrib/pageinspect/heapfuncs.c b/contrib/pageinspect/heapfuncs.c
index 3dd1a9bc2a..dac5b78efe 100644
--- a/contrib/pageinspect/heapfuncs.c
+++ b/contrib/pageinspect/heapfuncs.c
@@ -531,8 +531,8 @@ heap_tuple_infomask_flags(PG_FUNCTION_ARGS)
 		pg_popcount((const char *) &t_infomask2, sizeof(uint16));
 
 	/* Initialize values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(values, 0, sizeof(values));
+	memset(nulls, 0, sizeof(nulls));
 
 	/* If no flags, return a set of empty arrays */
 	if (bitcnt <= 0)
@@ -598,7 +598,7 @@ heap_tuple_infomask_flags(PG_FUNCTION_ARGS)
 	 * keeps the code simple.
 	 */
 	cnt = 0;
-	MemSet(flags, 0, sizeof(Datum) * bitcnt);
+	memset(flags, 0, sizeof(Datum) * bitcnt);
 
 	/* decode combined masks of t_infomask */
 	if ((t_infomask & HEAP_XMAX_SHR_LOCK) == HEAP_XMAX_SHR_LOCK)
diff --git a/contrib/pg_prewarm/autoprewarm.c b/contrib/pg_prewarm/autoprewarm.c
index c0c4f5d9ca..9daeb06950 100644
--- a/contrib/pg_prewarm/autoprewarm.c
+++ b/contrib/pg_prewarm/autoprewarm.c
@@ -819,7 +819,7 @@ apw_start_leader_worker(void)
 	BgwHandleStatus status;
 	pid_t		pid;
 
-	MemSet(&worker, 0, sizeof(BackgroundWorker));
+	memset(&worker, 0, sizeof(BackgroundWorker));
 	worker.bgw_flags = BGWORKER_SHMEM_ACCESS;
 	worker.bgw_start_time = BgWorkerStart_ConsistentState;
 	strcpy(worker.bgw_library_name, "pg_prewarm");
@@ -859,7 +859,7 @@ apw_start_database_worker(void)
 	BackgroundWorker worker;
 	BackgroundWorkerHandle *handle;
 
-	MemSet(&worker, 0, sizeof(BackgroundWorker));
+	memset(&worker, 0, sizeof(BackgroundWorker));
 	worker.bgw_flags =
 		BGWORKER_SHMEM_ACCESS | BGWORKER_BACKEND_DATABASE_CONNECTION;
 	worker.bgw_start_time = BgWorkerStart_ConsistentState;
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index 768cedd91a..cdf1267c0a 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -1869,8 +1869,8 @@ pg_stat_statements_info(PG_FUNCTION_ARGS)
 	if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
 		elog(ERROR, "return type must be a row type");
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(values, 0, sizeof(values));
+	memset(nulls, 0, sizeof(nulls));
 
 	/* Read global statistics for pg_stat_statements */
 	{
diff --git a/contrib/pg_trgm/trgm_gist.c b/contrib/pg_trgm/trgm_gist.c
index 6f28db7d1e..36f4f41019 100644
--- a/contrib/pg_trgm/trgm_gist.c
+++ b/contrib/pg_trgm/trgm_gist.c
@@ -95,7 +95,7 @@ makesign(BITVECP sign, TRGM *a, int siglen)
 	trgm	   *ptr = GETARR(a);
 	int32		tmp = 0;
 
-	MemSet((void *) sign, 0, siglen);
+	memset((void *) sign, 0, siglen);
 	SETBIT(sign, SIGLENBIT(siglen));	/* set last unused bit */
 	for (k = 0; k < len; k++)
 	{
@@ -914,7 +914,7 @@ gtrgm_picksplit(PG_FUNCTION_ARGS)
 			if (ISALLTRUE(datum_l) || cache[j].allistrue)
 			{
 				if (!ISALLTRUE(datum_l))
-					MemSet((void *) GETSIGN(datum_l), 0xff, siglen);
+					memset((void *) GETSIGN(datum_l), 0xff, siglen);
 			}
 			else
 			{
@@ -930,7 +930,7 @@ gtrgm_picksplit(PG_FUNCTION_ARGS)
 			if (ISALLTRUE(datum_r) || cache[j].allistrue)
 			{
 				if (!ISALLTRUE(datum_r))
-					MemSet((void *) GETSIGN(datum_r), 0xff, siglen);
+					memset((void *) GETSIGN(datum_r), 0xff, siglen);
 			}
 			else
 			{
diff --git a/contrib/pg_trgm/trgm_regexp.c b/contrib/pg_trgm/trgm_regexp.c
index 58d32ba946..0eabafdd0f 100644
--- a/contrib/pg_trgm/trgm_regexp.c
+++ b/contrib/pg_trgm/trgm_regexp.c
@@ -926,7 +926,7 @@ transformGraph(TrgmNFA *trgmNFA)
 	trgmNFA->nstates = 0;
 
 	/* Create initial state: ambiguous prefix, NFA's initial state */
-	MemSet(&initkey, 0, sizeof(initkey));
+	memset(&initkey, 0, sizeof(initkey));
 	initkey.prefix.colors[0] = COLOR_UNKNOWN;
 	initkey.prefix.colors[1] = COLOR_UNKNOWN;
 	initkey.nstate = pg_reg_getinitialstate(trgmNFA->regex);
@@ -1028,7 +1028,7 @@ addKey(TrgmNFA *trgmNFA, TrgmState *state, TrgmStateKey *key)
 	 * Ensure any pad bytes in destKey are zero, since it may get used as a
 	 * hashtable key by getState.
 	 */
-	MemSet(&destKey, 0, sizeof(destKey));
+	memset(&destKey, 0, sizeof(destKey));
 
 	/*
 	 * Compare key to each existing enter key of the state to check for
@@ -1209,7 +1209,7 @@ addArcs(TrgmNFA *trgmNFA, TrgmState *state)
 	 * Ensure any pad bytes in destKey are zero, since it may get used as a
 	 * hashtable key by getState.
 	 */
-	MemSet(&destKey, 0, sizeof(destKey));
+	memset(&destKey, 0, sizeof(destKey));
 
 	/*
 	 * Iterate over enter keys associated with this expanded-graph state. This
diff --git a/contrib/pg_visibility/pg_visibility.c b/contrib/pg_visibility/pg_visibility.c
index 1853c354e3..fbb37bd003 100644
--- a/contrib/pg_visibility/pg_visibility.c
+++ b/contrib/pg_visibility/pg_visibility.c
@@ -88,7 +88,7 @@ pg_visibility_map(PG_FUNCTION_ARGS)
 				 errmsg("invalid block number")));
 
 	tupdesc = pg_visibility_tupdesc(false, false);
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(nulls, 0, sizeof(nulls));
 
 	mapbits = (int32) visibilitymap_get_status(rel, blkno, &vmbuffer);
 	if (vmbuffer != InvalidBuffer)
@@ -130,7 +130,7 @@ pg_visibility(PG_FUNCTION_ARGS)
 				 errmsg("invalid block number")));
 
 	tupdesc = pg_visibility_tupdesc(false, true);
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(nulls, 0, sizeof(nulls));
 
 	mapbits = (int32) visibilitymap_get_status(rel, blkno, &vmbuffer);
 	if (vmbuffer != InvalidBuffer)
@@ -191,7 +191,7 @@ pg_visibility_map_rel(PG_FUNCTION_ARGS)
 		bool		nulls[3];
 		HeapTuple	tuple;
 
-		MemSet(nulls, 0, sizeof(nulls));
+		memset(nulls, 0, sizeof(nulls));
 		values[0] = Int64GetDatum(info->next);
 		values[1] = BoolGetDatum((info->bits[info->next] & (1 << 0)) != 0);
 		values[2] = BoolGetDatum((info->bits[info->next] & (1 << 1)) != 0);
@@ -236,7 +236,7 @@ pg_visibility_rel(PG_FUNCTION_ARGS)
 		bool		nulls[4];
 		HeapTuple	tuple;
 
-		MemSet(nulls, 0, sizeof(nulls));
+		memset(nulls, 0, sizeof(nulls));
 		values[0] = Int64GetDatum(info->next);
 		values[1] = BoolGetDatum((info->bits[info->next] & (1 << 0)) != 0);
 		values[2] = BoolGetDatum((info->bits[info->next] & (1 << 1)) != 0);
@@ -300,7 +300,7 @@ pg_visibility_map_summary(PG_FUNCTION_ARGS)
 	TupleDescInitEntry(tupdesc, (AttrNumber) 2, "all_frozen", INT8OID, -1, 0);
 	tupdesc = BlessTupleDesc(tupdesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(nulls, 0, sizeof(nulls));
 	values[0] = Int64GetDatum(all_visible);
 	values[1] = Int64GetDatum(all_frozen);
 
diff --git a/contrib/pg_walinspect/pg_walinspect.c b/contrib/pg_walinspect/pg_walinspect.c
index a082dfb331..7589f80b0e 100644
--- a/contrib/pg_walinspect/pg_walinspect.c
+++ b/contrib/pg_walinspect/pg_walinspect.c
@@ -266,8 +266,8 @@ pg_get_wal_record_info(PG_FUNCTION_ARGS)
 				 errmsg("could not read WAL at %X/%X",
 						LSN_FORMAT_ARGS(first_record))));
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(values, 0, sizeof(values));
+	memset(nulls, 0, sizeof(nulls));
 
 	GetWALRecordInfo(xlogreader, first_record, values, nulls,
 					 PG_GET_WAL_RECORD_INFO_COLS);
@@ -343,8 +343,8 @@ GetWALRecordsInfo(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
 
 	Assert(xlogreader);
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(values, 0, sizeof(values));
+	memset(nulls, 0, sizeof(nulls));
 
 	while (ReadNextXLogRecord(xlogreader, first_record) &&
 		   xlogreader->EndRecPtr <= end_lsn)
@@ -565,7 +565,7 @@ GetWalStats(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
 
 	xlogreader = InitXLogReaderState(start_lsn, &first_record);
 
-	MemSet(&stats, 0, sizeof(stats));
+	memset(&stats, 0, sizeof(stats));
 
 	while (ReadNextXLogRecord(xlogreader, first_record) &&
 		   xlogreader->EndRecPtr <= end_lsn)
@@ -578,8 +578,8 @@ GetWalStats(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
 	pfree(xlogreader->private_data);
 	XLogReaderFree(xlogreader);
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(values, 0, sizeof(values));
+	memset(nulls, 0, sizeof(nulls));
 
 	GetXLogSummaryStats(&stats, rsinfo, values, nulls,
 						PG_GET_WAL_STATS_COLS,
diff --git a/contrib/pgstattuple/pgstatindex.c b/contrib/pgstattuple/pgstatindex.c
index e1048e47ff..eae3909664 100644
--- a/contrib/pgstattuple/pgstatindex.c
+++ b/contrib/pgstattuple/pgstatindex.c
@@ -697,7 +697,7 @@ pgstathashindex(PG_FUNCTION_ARGS)
 	/*
 	 * Build and return the tuple
 	 */
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(nulls, 0, sizeof(nulls));
 	values[0] = Int32GetDatum(stats.version);
 	values[1] = Int64GetDatum((int64) stats.bucket_pages);
 	values[2] = Int64GetDatum((int64) stats.overflow_pages);
diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c
index 061ffaf329..aa6dbac347 100644
--- a/contrib/postgres_fdw/connection.c
+++ b/contrib/postgres_fdw/connection.c
@@ -1687,8 +1687,8 @@ postgres_fdw_get_connections(PG_FUNCTION_ARGS)
 
 		server = GetForeignServerExtended(entry->serverid, FSV_MISSING_OK);
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
+		memset(values, 0, sizeof(values));
+		memset(nulls, 0, sizeof(nulls));
 
 		/*
 		 * The foreign server may have been dropped in current explicit
diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c
index d56951153b..38b5c46f40 100644
--- a/contrib/postgres_fdw/postgres_fdw.c
+++ b/contrib/postgres_fdw/postgres_fdw.c
@@ -3332,7 +3332,7 @@ estimate_path_cost_size(PlannerInfo *root,
 			input_rows = ofpinfo->rows;
 
 			/* Collect statistics about aggregates for estimating costs. */
-			MemSet(&aggcosts, 0, sizeof(AggClauseCosts));
+			memset(&aggcosts, 0, sizeof(AggClauseCosts));
 			if (root->parse->hasAggs)
 			{
 				get_agg_clause_costs(root, AGGSPLIT_SIMPLE, &aggcosts);
diff --git a/contrib/tablefunc/tablefunc.c b/contrib/tablefunc/tablefunc.c
index e308228bde..bd6f6614f6 100644
--- a/contrib/tablefunc/tablefunc.c
+++ b/contrib/tablefunc/tablefunc.c
@@ -129,7 +129,7 @@ typedef struct crosstab_cat_desc
 do { \
 	crosstab_HashEnt *hentry; char key[MAX_CATNAME_LEN]; \
 	\
-	MemSet(key, 0, MAX_CATNAME_LEN); \
+	memset(key, 0, MAX_CATNAME_LEN); \
 	snprintf(key, MAX_CATNAME_LEN - 1, "%s", CATNAME); \
 	hentry = (crosstab_HashEnt*) hash_search(HASHTAB, \
 										 key, HASH_FIND, NULL); \
@@ -143,7 +143,7 @@ do { \
 do { \
 	crosstab_HashEnt *hentry; bool found; char key[MAX_CATNAME_LEN]; \
 	\
-	MemSet(key, 0, MAX_CATNAME_LEN); \
+	memset(key, 0, MAX_CATNAME_LEN); \
 	snprintf(key, MAX_CATNAME_LEN - 1, "%s", CATDESC->catname); \
 	hentry = (crosstab_HashEnt*) hash_search(HASHTAB, \
 										 key, HASH_ENTER, &found); \
diff --git a/src/backend/access/common/scankey.c b/src/backend/access/common/scankey.c
index ff2b608f2e..2355ac54ef 100644
--- a/src/backend/access/common/scankey.c
+++ b/src/backend/access/common/scankey.c
@@ -51,7 +51,7 @@ ScanKeyEntryInitialize(ScanKey entry,
 	else
 	{
 		Assert(flags & (SK_SEARCHNULL | SK_SEARCHNOTNULL));
-		MemSet(&entry->sk_func, 0, sizeof(entry->sk_func));
+		memset(&entry->sk_func, 0, sizeof(entry->sk_func));
 	}
 }
 
diff --git a/src/backend/access/common/tupdesc.c b/src/backend/access/common/tupdesc.c
index 9f41b1e854..8eb8575a5d 100644
--- a/src/backend/access/common/tupdesc.c
+++ b/src/backend/access/common/tupdesc.c
@@ -611,7 +611,7 @@ TupleDescInitEntry(TupleDesc desc,
 	 * attributes. Also, do nothing if caller wants to re-use the old attname.
 	 */
 	if (attributeName == NULL)
-		MemSet(NameStr(att->attname), 0, NAMEDATALEN);
+		memset(NameStr(att->attname), 0, NAMEDATALEN);
 	else if (attributeName != NameStr(att->attname))
 		namestrcpy(&(att->attname), attributeName);
 
diff --git a/src/backend/access/gin/ginutil.c b/src/backend/access/gin/ginutil.c
index 3d15701a01..01a365aad6 100644
--- a/src/backend/access/gin/ginutil.c
+++ b/src/backend/access/gin/ginutil.c
@@ -98,7 +98,7 @@ initGinState(GinState *state, Relation index)
 	TupleDesc	origTupdesc = RelationGetDescr(index);
 	int			i;
 
-	MemSet(state, 0, sizeof(GinState));
+	memset(state, 0, sizeof(GinState));
 
 	state->index = index;
 	state->oneCol = (origTupdesc->natts == 1);
diff --git a/src/backend/access/hash/hashovfl.c b/src/backend/access/hash/hashovfl.c
index e34cfc302d..86aa48d520 100644
--- a/src/backend/access/hash/hashovfl.c
+++ b/src/backend/access/hash/hashovfl.c
@@ -760,7 +760,7 @@ _hash_initbitmapbuffer(Buffer buf, uint16 bmsize, bool initpage)
 
 	/* set all of the bits to 1 */
 	freep = HashPageGetBitmap(pg);
-	MemSet(freep, 0xFF, bmsize);
+	memset(freep, 0xFF, bmsize);
 
 	/*
 	 * Set pd_lower just past the end of the bitmap page data.  We could even
diff --git a/src/backend/access/hash/hashpage.c b/src/backend/access/hash/hashpage.c
index 39206d1942..3f31dad231 100644
--- a/src/backend/access/hash/hashpage.c
+++ b/src/backend/access/hash/hashpage.c
@@ -572,8 +572,8 @@ _hash_init_metabuffer(Buffer buf, double num_tuples, RegProcedure procid,
 	metap->hashm_highmask = pg_nextpower2_32(num_buckets + 1) - 1;
 	metap->hashm_lowmask = (metap->hashm_highmask >> 1);
 
-	MemSet(metap->hashm_spares, 0, sizeof(metap->hashm_spares));
-	MemSet(metap->hashm_mapp, 0, sizeof(metap->hashm_mapp));
+	memset(metap->hashm_spares, 0, sizeof(metap->hashm_spares));
+	memset(metap->hashm_mapp, 0, sizeof(metap->hashm_mapp));
 
 	/* Set up mapping for one spare page after the initial splitpoints */
 	metap->hashm_spares[spare_index] = 1;
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index 7421851027..dffa798aad 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -9141,7 +9141,7 @@ heap_xlog_insert(XLogReaderState *record)
 		data += SizeOfHeapHeader;
 
 		htup = &tbuf.hdr;
-		MemSet((char *) htup, 0, SizeofHeapTupleHeader);
+		memset((char *) htup, 0, SizeofHeapTupleHeader);
 		/* PG73FORMAT: get bitmap [+ padding] [+ oid] + data */
 		memcpy((char *) htup + SizeofHeapTupleHeader,
 			   data,
@@ -9282,7 +9282,7 @@ heap_xlog_multi_insert(XLogReaderState *record)
 			newlen = xlhdr->datalen;
 			Assert(newlen <= MaxHeapTupleSize);
 			htup = &tbuf.hdr;
-			MemSet((char *) htup, 0, SizeofHeapTupleHeader);
+			memset((char *) htup, 0, SizeofHeapTupleHeader);
 			/* PG73FORMAT: get bitmap [+ padding] [+ oid] + data */
 			memcpy((char *) htup + SizeofHeapTupleHeader,
 				   (char *) tupdata,
@@ -9518,7 +9518,7 @@ heap_xlog_update(XLogReaderState *record, bool hot_update)
 		Assert(tuplen <= MaxHeapTupleSize);
 
 		htup = &tbuf.hdr;
-		MemSet((char *) htup, 0, SizeofHeapTupleHeader);
+		memset((char *) htup, 0, SizeofHeapTupleHeader);
 
 		/*
 		 * Reconstruct the new tuple using the prefix and/or suffix from the
diff --git a/src/backend/access/heap/pruneheap.c b/src/backend/access/heap/pruneheap.c
index 9f43bbe25f..c375c01804 100644
--- a/src/backend/access/heap/pruneheap.c
+++ b/src/backend/access/heap/pruneheap.c
@@ -1113,7 +1113,7 @@ heap_get_root_tuples(Page page, OffsetNumber *root_offsets)
 	OffsetNumber offnum,
 				maxoff;
 
-	MemSet(root_offsets, InvalidOffsetNumber,
+	memset(root_offsets, InvalidOffsetNumber,
 		   MaxHeapTuplesPerPage * sizeof(OffsetNumber));
 
 	maxoff = PageGetMaxOffsetNumber(page);
diff --git a/src/backend/access/heap/visibilitymap.c b/src/backend/access/heap/visibilitymap.c
index e09f25a684..f3fa73df81 100644
--- a/src/backend/access/heap/visibilitymap.c
+++ b/src/backend/access/heap/visibilitymap.c
@@ -494,7 +494,7 @@ visibilitymap_prepare_truncate(Relation rel, BlockNumber nheapblocks)
 		START_CRIT_SECTION();
 
 		/* Clear out the unwanted bytes. */
-		MemSet(&map[truncByte + 1], 0, MAPSIZE - (truncByte + 1));
+		memset(&map[truncByte + 1], 0, MAPSIZE - (truncByte + 1));
 
 		/*----
 		 * Mask out the unwanted bits of the last remaining byte.
diff --git a/src/backend/access/nbtree/nbtpage.c b/src/backend/access/nbtree/nbtpage.c
index 20adb602a4..129c4383ae 100644
--- a/src/backend/access/nbtree/nbtpage.c
+++ b/src/backend/access/nbtree/nbtpage.c
@@ -2220,7 +2220,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack)
 	opaque->btpo_flags |= BTP_HALF_DEAD;
 
 	Assert(PageGetMaxOffsetNumber(page) == P_HIKEY);
-	MemSet(&trunctuple, 0, sizeof(IndexTupleData));
+	memset(&trunctuple, 0, sizeof(IndexTupleData));
 	trunctuple.t_info = sizeof(IndexTupleData);
 	if (topparent != leafblkno)
 		BTreeTupleSetTopParent(&trunctuple, topparent);
diff --git a/src/backend/access/nbtree/nbtxlog.c b/src/backend/access/nbtree/nbtxlog.c
index f9186ca233..e40b586e97 100644
--- a/src/backend/access/nbtree/nbtxlog.c
+++ b/src/backend/access/nbtree/nbtxlog.c
@@ -780,7 +780,7 @@ btree_xlog_mark_page_halfdead(uint8 info, XLogReaderState *record)
 	 * Construct a dummy high key item that points to top parent page (value
 	 * is InvalidBlockNumber when the top parent page is the leaf page itself)
 	 */
-	MemSet(&trunctuple, 0, sizeof(IndexTupleData));
+	memset(&trunctuple, 0, sizeof(IndexTupleData));
 	trunctuple.t_info = sizeof(IndexTupleData);
 	BTreeTupleSetTopParent(&trunctuple, xlrec->topparent);
 
@@ -915,7 +915,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record)
 		pageop->btpo_cycleid = 0;
 
 		/* Add a dummy hikey item */
-		MemSet(&trunctuple, 0, sizeof(IndexTupleData));
+		memset(&trunctuple, 0, sizeof(IndexTupleData));
 		trunctuple.t_info = sizeof(IndexTupleData);
 		BTreeTupleSetTopParent(&trunctuple, xlrec->leaftopparent);
 
diff --git a/src/backend/access/transam/clog.c b/src/backend/access/transam/clog.c
index 3d9088a704..7e655c49b6 100644
--- a/src/backend/access/transam/clog.c
+++ b/src/backend/access/transam/clog.c
@@ -804,7 +804,7 @@ TrimCLOG(void)
 		/* Zero so-far-unused positions in the current byte */
 		*byteptr &= (1 << bshift) - 1;
 		/* Zero the rest of the page */
-		MemSet(byteptr + 1, 0, BLCKSZ - byteno - 1);
+		memset(byteptr + 1, 0, BLCKSZ - byteno - 1);
 
 		XactCtl->shared->page_dirty[slotno] = true;
 	}
diff --git a/src/backend/access/transam/multixact.c b/src/backend/access/transam/multixact.c
index 8f7d12950e..8b52f73800 100644
--- a/src/backend/access/transam/multixact.c
+++ b/src/backend/access/transam/multixact.c
@@ -1872,7 +1872,7 @@ MultiXactShmemInit(void)
 		Assert(!found);
 
 		/* Make sure we zero out the per-backend state */
-		MemSet(MultiXactState, 0, SHARED_MULTIXACT_STATE_SIZE);
+		memset(MultiXactState, 0, SHARED_MULTIXACT_STATE_SIZE);
 	}
 	else
 		Assert(found);
@@ -2072,7 +2072,7 @@ TrimMultiXact(void)
 		offptr = (MultiXactOffset *) MultiXactOffsetCtl->shared->page_buffer[slotno];
 		offptr += entryno;
 
-		MemSet(offptr, 0, BLCKSZ - (entryno * sizeof(MultiXactOffset)));
+		memset(offptr, 0, BLCKSZ - (entryno * sizeof(MultiXactOffset)));
 
 		MultiXactOffsetCtl->shared->page_dirty[slotno] = true;
 	}
@@ -2104,7 +2104,7 @@ TrimMultiXact(void)
 		xidptr = (TransactionId *)
 			(MultiXactMemberCtl->shared->page_buffer[slotno] + memberoff);
 
-		MemSet(xidptr, 0, BLCKSZ - memberoff);
+		memset(xidptr, 0, BLCKSZ - memberoff);
 
 		/*
 		 * Note: we don't need to zero out the flag bits in the remaining
diff --git a/src/backend/access/transam/slru.c b/src/backend/access/transam/slru.c
index b65cb49d7f..3781af2dee 100644
--- a/src/backend/access/transam/slru.c
+++ b/src/backend/access/transam/slru.c
@@ -296,7 +296,7 @@ SimpleLruZeroPage(SlruCtl ctl, int pageno)
 	SlruRecentlyUsed(shared, slotno);
 
 	/* Set the buffer to zeroes */
-	MemSet(shared->page_buffer[slotno], 0, BLCKSZ);
+	memset(shared->page_buffer[slotno], 0, BLCKSZ);
 
 	/* Set the LSNs for this new page to zero */
 	SimpleLruZeroLSNs(ctl, slotno);
@@ -326,7 +326,7 @@ SimpleLruZeroLSNs(SlruCtl ctl, int slotno)
 	SlruShared	shared = ctl->shared;
 
 	if (shared->lsn_groups_per_page > 0)
-		MemSet(&shared->group_lsn[slotno * shared->lsn_groups_per_page], 0,
+		memset(&shared->group_lsn[slotno * shared->lsn_groups_per_page], 0,
 			   shared->lsn_groups_per_page * sizeof(XLogRecPtr));
 }
 
@@ -712,7 +712,7 @@ SlruPhysicalReadPage(SlruCtl ctl, int pageno, int slotno)
 		ereport(LOG,
 				(errmsg("file \"%s\" doesn't exist, reading as zeroes",
 						path)));
-		MemSet(shared->page_buffer[slotno], 0, BLCKSZ);
+		memset(shared->page_buffer[slotno], 0, BLCKSZ);
 		return true;
 	}
 
diff --git a/src/backend/access/transam/twophase.c b/src/backend/access/transam/twophase.c
index 75551f60cb..1fd2e20ece 100644
--- a/src/backend/access/transam/twophase.c
+++ b/src/backend/access/transam/twophase.c
@@ -459,7 +459,7 @@ MarkAsPreparingGuts(GlobalTransaction gxact, TransactionId xid, const char *gid,
 	proc = &ProcGlobal->allProcs[gxact->pgprocno];
 
 	/* Initialize the PGPROC entry */
-	MemSet(proc, 0, sizeof(PGPROC));
+	memset(proc, 0, sizeof(PGPROC));
 	proc->pgprocno = gxact->pgprocno;
 	SHMQueueElemInit(&(proc->links));
 	proc->waitStatus = PROC_WAIT_STATUS_OK;
@@ -791,8 +791,8 @@ pg_prepared_xact(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
+		memset(values, 0, sizeof(values));
+		memset(nulls, 0, sizeof(nulls));
 
 		values[0] = TransactionIdGetDatum(proc->xid);
 		values[1] = CStringGetTextDatum(gxact->gid);
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 71136b11a2..46a24d5a73 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1280,7 +1280,7 @@ CopyXLogRecordToWAL(int write_len, bool isLogSwitch, XLogRecData *rdata,
 			 * and zero most of the page.  Then we just zero the page header.
 			 */
 			currpos = GetXLogBuffer(CurrPos, tli);
-			MemSet(currpos, 0, SizeOfXLogShortPHD);
+			memset(currpos, 0, SizeOfXLogShortPHD);
 
 			CurrPos += XLOG_BLCKSZ;
 		}
@@ -1868,7 +1868,7 @@ AdvanceXLInsertBuffer(XLogRecPtr upto, TimeLineID tli, bool opportunistic)
 		 * Be sure to re-zero the buffer so that bytes beyond what we've
 		 * written will look like zeroes and not valid XLOG records...
 		 */
-		MemSet((char *) NewPage, 0, XLOG_BLCKSZ);
+		memset((char *) NewPage, 0, XLOG_BLCKSZ);
 
 		/*
 		 * Fill the new page's header
@@ -6302,7 +6302,7 @@ CreateCheckPoint(int flags)
 	 * checkpoint proceeds, we always accumulate stats, even if
 	 * log_checkpoints is currently off.
 	 */
-	MemSet(&CheckpointStats, 0, sizeof(CheckpointStats));
+	memset(&CheckpointStats, 0, sizeof(CheckpointStats));
 	CheckpointStats.ckpt_start_t = GetCurrentTimestamp();
 
 	/*
@@ -6327,7 +6327,7 @@ CreateCheckPoint(int flags)
 	}
 
 	/* Begin filling in the checkpoint WAL record */
-	MemSet(&checkPoint, 0, sizeof(checkPoint));
+	memset(&checkPoint, 0, sizeof(checkPoint));
 	checkPoint.time = (pg_time_t) time(NULL);
 
 	/*
@@ -6999,7 +6999,7 @@ CreateRestartPoint(int flags)
 	 * checkpoint proceeds, we always accumulate stats, even if
 	 * log_checkpoints is currently off.
 	 */
-	MemSet(&CheckpointStats, 0, sizeof(CheckpointStats));
+	memset(&CheckpointStats, 0, sizeof(CheckpointStats));
 	CheckpointStats.ckpt_start_t = GetCurrentTimestamp();
 
 	if (log_checkpoints)
diff --git a/src/backend/access/transam/xlogfuncs.c b/src/backend/access/transam/xlogfuncs.c
index 02bd919ff6..7bc2fa360a 100644
--- a/src/backend/access/transam/xlogfuncs.c
+++ b/src/backend/access/transam/xlogfuncs.c
@@ -117,8 +117,8 @@ pg_backup_stop(PG_FUNCTION_ARGS)
 	if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
 		elog(ERROR, "return type must be a row type");
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(values, 0, sizeof(values));
+	memset(nulls, 0, sizeof(nulls));
 
 	if (status != SESSION_BACKUP_RUNNING)
 		ereport(ERROR,
diff --git a/src/backend/access/transam/xloginsert.c b/src/backend/access/transam/xloginsert.c
index 2ce9be2cc7..5255401524 100644
--- a/src/backend/access/transam/xloginsert.c
+++ b/src/backend/access/transam/xloginsert.c
@@ -204,7 +204,7 @@ XLogEnsureRecordSpace(int max_block_id, int ndatas)
 		 * At least the padding bytes in the structs must be zeroed, because
 		 * they are included in WAL data, but initialize it all for tidiness.
 		 */
-		MemSet(&registered_buffers[max_registered_buffers], 0,
+		memset(&registered_buffers[max_registered_buffers], 0,
 			   (nbuffers - max_registered_buffers) * sizeof(registered_buffer));
 		max_registered_buffers = nbuffers;
 	}
diff --git a/src/backend/access/transam/xlogreader.c b/src/backend/access/transam/xlogreader.c
index cf5db23cb8..28dc1e02c5 100644
--- a/src/backend/access/transam/xlogreader.c
+++ b/src/backend/access/transam/xlogreader.c
@@ -2093,7 +2093,7 @@ RestoreBlockImage(XLogReaderState *record, uint8 block_id, char *page)
 	{
 		memcpy(page, ptr, bkpb->hole_offset);
 		/* must zero-fill the hole */
-		MemSet(page + bkpb->hole_offset, 0, bkpb->hole_length);
+		memset(page + bkpb->hole_offset, 0, bkpb->hole_length);
 		memcpy(page + (bkpb->hole_offset + bkpb->hole_length),
 			   ptr + bkpb->hole_offset,
 			   BLCKSZ - (bkpb->hole_offset + bkpb->hole_length));
diff --git a/src/backend/bootstrap/bootstrap.c b/src/backend/bootstrap/bootstrap.c
index 9fa8fdd4cf..9cf2f1348c 100644
--- a/src/backend/bootstrap/bootstrap.c
+++ b/src/backend/bootstrap/bootstrap.c
@@ -513,7 +513,7 @@ DefineAttr(char *name, char *type, int attnum, int nullness)
 
 	if (attrtypes[attnum] == NULL)
 		attrtypes[attnum] = AllocateAttribute();
-	MemSet(attrtypes[attnum], 0, ATTRIBUTE_FIXED_PART_SIZE);
+	memset(attrtypes[attnum], 0, ATTRIBUTE_FIXED_PART_SIZE);
 
 	namestrcpy(&attrtypes[attnum]->attname, name);
 	elog(DEBUG4, "column %s %s", NameStr(attrtypes[attnum]->attname), type);
diff --git a/src/backend/catalog/aclchk.c b/src/backend/catalog/aclchk.c
index 5f1726c095..2bc981ace0 100644
--- a/src/backend/catalog/aclchk.c
+++ b/src/backend/catalog/aclchk.c
@@ -1344,9 +1344,9 @@ SetDefaultACL(InternalDefaultACL *iacls)
 		Oid			defAclOid;
 
 		/* Prepare to insert or update pg_default_acl entry */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
+		memset(values, 0, sizeof(values));
+		memset(nulls, false, sizeof(nulls));
+		memset(replaces, false, sizeof(replaces));
 
 		if (isNew)
 		{
@@ -1745,9 +1745,9 @@ ExecGrant_Attribute(InternalGrant *istmt, Oid relOid, const char *relname,
 	nnewmembers = aclmembers(new_acl, &newmembers);
 
 	/* finished building new ACL value, now insert it */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, false, sizeof(nulls));
-	MemSet(replaces, false, sizeof(replaces));
+	memset(values, 0, sizeof(values));
+	memset(nulls, false, sizeof(nulls));
+	memset(replaces, false, sizeof(replaces));
 
 	/*
 	 * If the updated ACL is empty, we can set attacl to null, and maybe even
@@ -2027,9 +2027,9 @@ ExecGrant_Relation(InternalGrant *istmt)
 			nnewmembers = aclmembers(new_acl, &newmembers);
 
 			/* finished building new ACL value, now insert it */
-			MemSet(values, 0, sizeof(values));
-			MemSet(nulls, false, sizeof(nulls));
-			MemSet(replaces, false, sizeof(replaces));
+			memset(values, 0, sizeof(values));
+			memset(nulls, false, sizeof(nulls));
+			memset(replaces, false, sizeof(replaces));
 
 			replaces[Anum_pg_class_relacl - 1] = true;
 			values[Anum_pg_class_relacl - 1] = PointerGetDatum(new_acl);
@@ -2217,9 +2217,9 @@ ExecGrant_Database(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
+		memset(values, 0, sizeof(values));
+		memset(nulls, false, sizeof(nulls));
+		memset(replaces, false, sizeof(replaces));
 
 		replaces[Anum_pg_database_datacl - 1] = true;
 		values[Anum_pg_database_datacl - 1] = PointerGetDatum(new_acl);
@@ -2339,9 +2339,9 @@ ExecGrant_Fdw(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
+		memset(values, 0, sizeof(values));
+		memset(nulls, false, sizeof(nulls));
+		memset(replaces, false, sizeof(replaces));
 
 		replaces[Anum_pg_foreign_data_wrapper_fdwacl - 1] = true;
 		values[Anum_pg_foreign_data_wrapper_fdwacl - 1] = PointerGetDatum(new_acl);
@@ -2465,9 +2465,9 @@ ExecGrant_ForeignServer(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
+		memset(values, 0, sizeof(values));
+		memset(nulls, false, sizeof(nulls));
+		memset(replaces, false, sizeof(replaces));
 
 		replaces[Anum_pg_foreign_server_srvacl - 1] = true;
 		values[Anum_pg_foreign_server_srvacl - 1] = PointerGetDatum(new_acl);
@@ -2589,9 +2589,9 @@ ExecGrant_Function(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
+		memset(values, 0, sizeof(values));
+		memset(nulls, false, sizeof(nulls));
+		memset(replaces, false, sizeof(replaces));
 
 		replaces[Anum_pg_proc_proacl - 1] = true;
 		values[Anum_pg_proc_proacl - 1] = PointerGetDatum(new_acl);
@@ -2720,9 +2720,9 @@ ExecGrant_Language(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
+		memset(values, 0, sizeof(values));
+		memset(nulls, false, sizeof(nulls));
+		memset(replaces, false, sizeof(replaces));
 
 		replaces[Anum_pg_language_lanacl - 1] = true;
 		values[Anum_pg_language_lanacl - 1] = PointerGetDatum(new_acl);
@@ -2858,9 +2858,9 @@ ExecGrant_Largeobject(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
+		memset(values, 0, sizeof(values));
+		memset(nulls, false, sizeof(nulls));
+		memset(replaces, false, sizeof(replaces));
 
 		replaces[Anum_pg_largeobject_metadata_lomacl - 1] = true;
 		values[Anum_pg_largeobject_metadata_lomacl - 1]
@@ -2984,9 +2984,9 @@ ExecGrant_Namespace(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
+		memset(values, 0, sizeof(values));
+		memset(nulls, false, sizeof(nulls));
+		memset(replaces, false, sizeof(replaces));
 
 		replaces[Anum_pg_namespace_nspacl - 1] = true;
 		values[Anum_pg_namespace_nspacl - 1] = PointerGetDatum(new_acl);
@@ -3108,9 +3108,9 @@ ExecGrant_Tablespace(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
+		memset(values, 0, sizeof(values));
+		memset(nulls, false, sizeof(nulls));
+		memset(replaces, false, sizeof(replaces));
 
 		replaces[Anum_pg_tablespace_spcacl - 1] = true;
 		values[Anum_pg_tablespace_spcacl - 1] = PointerGetDatum(new_acl);
@@ -3242,9 +3242,9 @@ ExecGrant_Type(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
+		memset(values, 0, sizeof(values));
+		memset(nulls, false, sizeof(nulls));
+		memset(replaces, false, sizeof(replaces));
 
 		replaces[Anum_pg_type_typacl - 1] = true;
 		values[Anum_pg_type_typacl - 1] = PointerGetDatum(new_acl);
@@ -3388,9 +3388,9 @@ ExecGrant_Parameter(InternalGrant *istmt)
 			bool		nulls[Natts_pg_parameter_acl];
 			bool		replaces[Natts_pg_parameter_acl];
 
-			MemSet(values, 0, sizeof(values));
-			MemSet(nulls, false, sizeof(nulls));
-			MemSet(replaces, false, sizeof(replaces));
+			memset(values, 0, sizeof(values));
+			memset(nulls, false, sizeof(nulls));
+			memset(replaces, false, sizeof(replaces));
 
 			replaces[Anum_pg_parameter_acl_paracl - 1] = true;
 			values[Anum_pg_parameter_acl_paracl - 1] = PointerGetDatum(new_acl);
@@ -6426,9 +6426,9 @@ recordExtensionInitPrivWorker(Oid objoid, Oid classoid, int objsubid, Acl *new_a
 		/* If we have a new ACL to set, then update the row with it. */
 		if (new_acl)
 		{
-			MemSet(values, 0, sizeof(values));
-			MemSet(nulls, false, sizeof(nulls));
-			MemSet(replace, false, sizeof(replace));
+			memset(values, 0, sizeof(values));
+			memset(nulls, false, sizeof(nulls));
+			memset(replace, false, sizeof(replace));
 
 			values[Anum_pg_init_privs_initprivs - 1] = PointerGetDatum(new_acl);
 			replace[Anum_pg_init_privs_initprivs - 1] = true;
@@ -6458,7 +6458,7 @@ recordExtensionInitPrivWorker(Oid objoid, Oid classoid, int objsubid, Acl *new_a
 		if (new_acl)
 		{
 			/* No entry found, so add it. */
-			MemSet(nulls, false, sizeof(nulls));
+			memset(nulls, false, sizeof(nulls));
 
 			values[Anum_pg_init_privs_objoid - 1] = ObjectIdGetDatum(objoid);
 			values[Anum_pg_init_privs_classoid - 1] = ObjectIdGetDatum(classoid);
diff --git a/src/backend/catalog/dependency.c b/src/backend/catalog/dependency.c
index de10923391..e853de5bac 100644
--- a/src/backend/catalog/dependency.c
+++ b/src/backend/catalog/dependency.c
@@ -1640,7 +1640,7 @@ recordDependencyOnSingleRelExpr(const ObjectAddress *depender,
 	context.addrs = new_object_addresses();
 
 	/* We gin up a rather bogus rangetable list to handle Vars */
-	MemSet(&rte, 0, sizeof(rte));
+	memset(&rte, 0, sizeof(rte));
 	rte.type = T_RangeTblEntry;
 	rte.rtekind = RTE_RELATION;
 	rte.relid = relId;
diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c
index 1803194db9..75c0610e46 100644
--- a/src/backend/catalog/heap.c
+++ b/src/backend/catalog/heap.c
@@ -1714,9 +1714,9 @@ RemoveAttributeById(Oid relid, AttrNumber attnum)
 			bool		replacesAtt[Natts_pg_attribute];
 
 			/* update the tuple - set atthasmissing and attmissingval */
-			MemSet(valuesAtt, 0, sizeof(valuesAtt));
-			MemSet(nullsAtt, false, sizeof(nullsAtt));
-			MemSet(replacesAtt, false, sizeof(replacesAtt));
+			memset(valuesAtt, 0, sizeof(valuesAtt));
+			memset(nullsAtt, false, sizeof(nullsAtt));
+			memset(replacesAtt, false, sizeof(replacesAtt));
 
 			valuesAtt[Anum_pg_attribute_atthasmissing - 1] =
 				BoolGetDatum(false);
@@ -2041,9 +2041,9 @@ SetAttrMissing(Oid relid, char *attname, char *value)
 								  Int32GetDatum(attStruct->atttypmod));
 
 	/* update the tuple - set atthasmissing and attmissingval */
-	MemSet(valuesAtt, 0, sizeof(valuesAtt));
-	MemSet(nullsAtt, false, sizeof(nullsAtt));
-	MemSet(replacesAtt, false, sizeof(replacesAtt));
+	memset(valuesAtt, 0, sizeof(valuesAtt));
+	memset(nullsAtt, false, sizeof(nullsAtt));
+	memset(replacesAtt, false, sizeof(replacesAtt));
 
 	valuesAtt[Anum_pg_attribute_atthasmissing - 1] = BoolGetDatum(true);
 	replacesAtt[Anum_pg_attribute_atthasmissing - 1] = true;
@@ -3347,7 +3347,7 @@ StorePartitionKey(Relation rel,
 
 	pg_partitioned_table = table_open(PartitionedRelationId, RowExclusiveLock);
 
-	MemSet(nulls, false, sizeof(nulls));
+	memset(nulls, false, sizeof(nulls));
 
 	/* Only this can ever be NULL */
 	if (!partexprDatum)
diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c
index bdd3c34841..99d176846c 100644
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@@ -309,7 +309,7 @@ ConstructTupleDescriptor(Relation heapRelation,
 		Form_pg_opclass opclassTup;
 		Oid			keyType;
 
-		MemSet(to, 0, ATTRIBUTE_FIXED_PART_SIZE);
+		memset(to, 0, ATTRIBUTE_FIXED_PART_SIZE);
 		to->attnum = i + 1;
 		to->attstattarget = -1;
 		to->attcacheoff = -1;
@@ -607,7 +607,7 @@ UpdateIndexRelation(Oid indexoid,
 	/*
 	 * Build a pg_index tuple
 	 */
-	MemSet(nulls, false, sizeof(nulls));
+	memset(nulls, false, sizeof(nulls));
 
 	values[Anum_pg_index_indexrelid - 1] = ObjectIdGetDatum(indexoid);
 	values[Anum_pg_index_indrelid - 1] = ObjectIdGetDatum(heapoid);
diff --git a/src/backend/catalog/pg_attrdef.c b/src/backend/catalog/pg_attrdef.c
index c5d4a9912e..11c61f4970 100644
--- a/src/backend/catalog/pg_attrdef.c
+++ b/src/backend/catalog/pg_attrdef.c
@@ -117,9 +117,9 @@ StoreAttrDefault(Relation rel, AttrNumber attnum,
 		Datum		missingval = (Datum) 0;
 		bool		missingIsNull = true;
 
-		MemSet(valuesAtt, 0, sizeof(valuesAtt));
-		MemSet(nullsAtt, false, sizeof(nullsAtt));
-		MemSet(replacesAtt, false, sizeof(replacesAtt));
+		memset(valuesAtt, 0, sizeof(valuesAtt));
+		memset(nullsAtt, false, sizeof(nullsAtt));
+		memset(replacesAtt, false, sizeof(replacesAtt));
 		valuesAtt[Anum_pg_attribute_atthasdef - 1] = true;
 		replacesAtt[Anum_pg_attribute_atthasdef - 1] = true;
 
diff --git a/src/backend/catalog/pg_cast.c b/src/backend/catalog/pg_cast.c
index 4857f6468d..cbf49817cf 100644
--- a/src/backend/catalog/pg_cast.c
+++ b/src/backend/catalog/pg_cast.c
@@ -78,7 +78,7 @@ CastCreate(Oid sourcetypeid, Oid targettypeid, Oid funcid, char castcontext,
 	values[Anum_pg_cast_castcontext - 1] = CharGetDatum(castcontext);
 	values[Anum_pg_cast_castmethod - 1] = CharGetDatum(castmethod);
 
-	MemSet(nulls, false, sizeof(nulls));
+	memset(nulls, false, sizeof(nulls));
 
 	tuple = heap_form_tuple(RelationGetDescr(relation), values, nulls);
 
diff --git a/src/backend/catalog/pg_parameter_acl.c b/src/backend/catalog/pg_parameter_acl.c
index 2decee909b..4afeb7218c 100644
--- a/src/backend/catalog/pg_parameter_acl.c
+++ b/src/backend/catalog/pg_parameter_acl.c
@@ -98,8 +98,8 @@ ParameterAclCreate(const char *parameter)
 	 */
 	rel = table_open(ParameterAclRelationId, RowExclusiveLock);
 	tupDesc = RelationGetDescr(rel);
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, false, sizeof(nulls));
+	memset(values, 0, sizeof(values));
+	memset(nulls, false, sizeof(nulls));
 	parameterId = GetNewOidWithIndex(rel,
 									 ParameterAclOidIndexId,
 									 Anum_pg_parameter_acl_oid);
diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 8c7fca62de..7aa7a019c9 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -1168,8 +1168,8 @@ pg_get_publication_tables(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(nulls, 0, sizeof(nulls));
-		MemSet(values, 0, sizeof(values));
+		memset(nulls, 0, sizeof(nulls));
+		memset(values, 0, sizeof(values));
 
 		publication = GetPublicationByName(pubname, false);
 
diff --git a/src/backend/catalog/storage.c b/src/backend/catalog/storage.c
index c06e414a38..b8ce4749ed 100644
--- a/src/backend/catalog/storage.c
+++ b/src/backend/catalog/storage.c
@@ -613,7 +613,7 @@ SerializePendingSyncs(Size maxSize, char *startAddress)
 	hash_destroy(tmphash);
 
 terminate:
-	MemSet(dest, 0, sizeof(RelFileNode));
+	memset(dest, 0, sizeof(RelFileNode));
 }
 
 /*
diff --git a/src/backend/commands/copyfromparse.c b/src/backend/commands/copyfromparse.c
index edb80e2cd5..b1d07f911d 100644
--- a/src/backend/commands/copyfromparse.c
+++ b/src/backend/commands/copyfromparse.c
@@ -867,8 +867,8 @@ NextCopyFrom(CopyFromState cstate, ExprContext *econtext,
 	attr_count = list_length(cstate->attnumlist);
 
 	/* Initialize all values for row to NULL */
-	MemSet(values, 0, num_phys_attrs * sizeof(Datum));
-	MemSet(nulls, true, num_phys_attrs * sizeof(bool));
+	memset(values, 0, num_phys_attrs * sizeof(Datum));
+	memset(nulls, true, num_phys_attrs * sizeof(bool));
 
 	if (!cstate->opts.binary)
 	{
diff --git a/src/backend/commands/dbcommands.c b/src/backend/commands/dbcommands.c
index f269168401..70e87ee559 100644
--- a/src/backend/commands/dbcommands.c
+++ b/src/backend/commands/dbcommands.c
@@ -1296,8 +1296,8 @@ createdb(ParseState *pstate, const CreatedbStmt *stmt)
 		   (dblocprovider != COLLPROVIDER_ICU && !dbiculocale));
 
 	/* Form tuple */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
+	memset(new_record, 0, sizeof(new_record));
+	memset(new_record_nulls, false, sizeof(new_record_nulls));
 
 	new_record[Anum_pg_database_oid - 1] = ObjectIdGetDatum(dboid);
 	new_record[Anum_pg_database_datname - 1] =
@@ -2042,9 +2042,9 @@ movedb(const char *dbname, const char *tblspcname)
 					(errcode(ERRCODE_UNDEFINED_DATABASE),
 					 errmsg("database \"%s\" does not exist", dbname)));
 
-		MemSet(new_record, 0, sizeof(new_record));
-		MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-		MemSet(new_record_repl, false, sizeof(new_record_repl));
+		memset(new_record, 0, sizeof(new_record));
+		memset(new_record_nulls, false, sizeof(new_record_nulls));
+		memset(new_record_repl, false, sizeof(new_record_repl));
 
 		new_record[Anum_pg_database_dattablespace - 1] = ObjectIdGetDatum(dst_tblspcoid);
 		new_record_repl[Anum_pg_database_dattablespace - 1] = true;
@@ -2305,9 +2305,9 @@ AlterDatabase(ParseState *pstate, AlterDatabaseStmt *stmt, bool isTopLevel)
 	/*
 	 * Build an updated tuple, perusing the information just obtained
 	 */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-	MemSet(new_record_repl, false, sizeof(new_record_repl));
+	memset(new_record, 0, sizeof(new_record));
+	memset(new_record_nulls, false, sizeof(new_record_nulls));
+	memset(new_record_repl, false, sizeof(new_record_repl));
 
 	if (distemplate)
 	{
diff --git a/src/backend/commands/event_trigger.c b/src/backend/commands/event_trigger.c
index 4642527881..b927a3f479 100644
--- a/src/backend/commands/event_trigger.c
+++ b/src/backend/commands/event_trigger.c
@@ -1316,8 +1316,8 @@ pg_event_trigger_dropped_objects(PG_FUNCTION_ARGS)
 
 		obj = slist_container(SQLDropObject, next, iter.cur);
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
+		memset(values, 0, sizeof(values));
+		memset(nulls, 0, sizeof(nulls));
 
 		/* classid */
 		values[i++] = ObjectIdGetDatum(obj->address.classId);
@@ -1859,7 +1859,7 @@ pg_event_trigger_ddl_commands(PG_FUNCTION_ARGS)
 			!OidIsValid(cmd->d.simple.address.objectId))
 			continue;
 
-		MemSet(nulls, 0, sizeof(nulls));
+		memset(nulls, 0, sizeof(nulls));
 
 		switch (cmd->type)
 		{
diff --git a/src/backend/commands/functioncmds.c b/src/backend/commands/functioncmds.c
index 00a6d282cf..b14cc774c0 100644
--- a/src/backend/commands/functioncmds.c
+++ b/src/backend/commands/functioncmds.c
@@ -1917,7 +1917,7 @@ CreateTransform(CreateTransformStmt *stmt)
 	values[Anum_pg_transform_trffromsql - 1] = ObjectIdGetDatum(fromsqlfuncid);
 	values[Anum_pg_transform_trftosql - 1] = ObjectIdGetDatum(tosqlfuncid);
 
-	MemSet(nulls, false, sizeof(nulls));
+	memset(nulls, false, sizeof(nulls));
 
 	relation = table_open(TransformRelationId, RowExclusiveLock);
 
@@ -1935,7 +1935,7 @@ CreateTransform(CreateTransformStmt *stmt)
 							format_type_be(typeid),
 							stmt->lang)));
 
-		MemSet(replaces, false, sizeof(replaces));
+		memset(replaces, false, sizeof(replaces));
 		replaces[Anum_pg_transform_trffromsql - 1] = true;
 		replaces[Anum_pg_transform_trftosql - 1] = true;
 
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 80738547ed..eeb77991b0 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -686,7 +686,7 @@ pg_prepared_statement(PG_FUNCTION_ARGS)
 			Datum		values[7];
 			bool		nulls[7];
 
-			MemSet(nulls, 0, sizeof(nulls));
+			memset(nulls, 0, sizeof(nulls));
 
 			values[0] = CStringGetTextDatum(prep_stmt->stmt_name);
 			values[1] = CStringGetTextDatum(prep_stmt->plansource->query_string);
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 2de0ebacec..1f180306c2 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -9112,15 +9112,15 @@ ATAddForeignKeyConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
 	 * Look up the referencing attributes to make sure they exist, and record
 	 * their attnums and type OIDs.
 	 */
-	MemSet(pkattnum, 0, sizeof(pkattnum));
-	MemSet(fkattnum, 0, sizeof(fkattnum));
-	MemSet(pktypoid, 0, sizeof(pktypoid));
-	MemSet(fktypoid, 0, sizeof(fktypoid));
-	MemSet(opclasses, 0, sizeof(opclasses));
-	MemSet(pfeqoperators, 0, sizeof(pfeqoperators));
-	MemSet(ppeqoperators, 0, sizeof(ppeqoperators));
-	MemSet(ffeqoperators, 0, sizeof(ffeqoperators));
-	MemSet(fkdelsetcols, 0, sizeof(fkdelsetcols));
+	memset(pkattnum, 0, sizeof(pkattnum));
+	memset(fkattnum, 0, sizeof(fkattnum));
+	memset(pktypoid, 0, sizeof(pktypoid));
+	memset(fktypoid, 0, sizeof(fktypoid));
+	memset(opclasses, 0, sizeof(opclasses));
+	memset(pfeqoperators, 0, sizeof(pfeqoperators));
+	memset(ppeqoperators, 0, sizeof(ppeqoperators));
+	memset(ffeqoperators, 0, sizeof(ffeqoperators));
+	memset(fkdelsetcols, 0, sizeof(fkdelsetcols));
 
 	numfks = transformColumnNameList(RelationGetRelid(rel),
 									 fkconstraint->fk_attrs,
@@ -11508,7 +11508,7 @@ validateForeignKeyConstraint(char *conname,
 	/*
 	 * Build a trigger call structure; we'll need it either way.
 	 */
-	MemSet(&trig, 0, sizeof(trig));
+	memset(&trig, 0, sizeof(trig));
 	trig.tgoid = InvalidOid;
 	trig.tgname = conname;
 	trig.tgenabled = TRIGGER_FIRES_ON_ORIGIN;
@@ -11553,7 +11553,7 @@ validateForeignKeyConstraint(char *conname,
 		 *
 		 * No parameters are passed, but we do set a context
 		 */
-		MemSet(fcinfo, 0, SizeForFunctionCallInfo(0));
+		memset(fcinfo, 0, SizeForFunctionCallInfo(0));
 
 		/*
 		 * We assume RI_FKey_check_ins won't look at flinfo...
@@ -12787,9 +12787,9 @@ ATExecAlterColumnType(AlteredTableInfo *tab, Relation rel,
 			bool		replacesAtt[Natts_pg_attribute];
 			HeapTuple	newTup;
 
-			MemSet(valuesAtt, 0, sizeof(valuesAtt));
-			MemSet(nullsAtt, false, sizeof(nullsAtt));
-			MemSet(replacesAtt, false, sizeof(replacesAtt));
+			memset(valuesAtt, 0, sizeof(valuesAtt));
+			memset(nullsAtt, false, sizeof(nullsAtt));
+			memset(replacesAtt, false, sizeof(replacesAtt));
 
 			missingval = array_get_element(missingval,
 										   1,
@@ -19231,7 +19231,7 @@ ATDetachCheckNoForeignKeyRefs(Relation partition)
 		/* prevent data changes into the referencing table until commit */
 		rel = table_open(constrForm->conrelid, ShareLock);
 
-		MemSet(&trig, 0, sizeof(trig));
+		memset(&trig, 0, sizeof(trig));
 		trig.tgoid = InvalidOid;
 		trig.tgname = NameStr(constrForm->conname);
 		trig.tgenabled = TRIGGER_FIRES_ON_ORIGIN;
diff --git a/src/backend/commands/tablespace.c b/src/backend/commands/tablespace.c
index 00ca397fe8..b55f07f092 100644
--- a/src/backend/commands/tablespace.c
+++ b/src/backend/commands/tablespace.c
@@ -340,7 +340,7 @@ CreateTableSpace(CreateTableSpaceStmt *stmt)
 	 */
 	rel = table_open(TableSpaceRelationId, RowExclusiveLock);
 
-	MemSet(nulls, false, sizeof(nulls));
+	memset(nulls, false, sizeof(nulls));
 
 	if (IsBinaryUpgrade)
 	{
diff --git a/src/backend/commands/typecmds.c b/src/backend/commands/typecmds.c
index 9b92b04242..5b91f14a7e 100644
--- a/src/backend/commands/typecmds.c
+++ b/src/backend/commands/typecmds.c
@@ -2596,9 +2596,9 @@ AlterDomainDefault(List *names, Node *defaultRaw)
 	checkDomainOwner(tup);
 
 	/* Setup new tuple */
-	MemSet(new_record, (Datum) 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-	MemSet(new_record_repl, false, sizeof(new_record_repl));
+	memset(new_record, (Datum) 0, sizeof(new_record));
+	memset(new_record_nulls, false, sizeof(new_record_nulls));
+	memset(new_record_repl, false, sizeof(new_record_repl));
 
 	/* Store the new default into the tuple */
 	if (defaultRaw)
diff --git a/src/backend/commands/user.c b/src/backend/commands/user.c
index 984305ba31..61a28e2098 100644
--- a/src/backend/commands/user.c
+++ b/src/backend/commands/user.c
@@ -338,8 +338,8 @@ CreateRole(ParseState *pstate, CreateRoleStmt *stmt)
 	/*
 	 * Build a tuple to insert
 	 */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
+	memset(new_record, 0, sizeof(new_record));
+	memset(new_record_nulls, false, sizeof(new_record_nulls));
 
 	new_record[Anum_pg_authid_rolname - 1] =
 		DirectFunctionCall1(namein, CStringGetDatum(stmt->role));
@@ -691,9 +691,9 @@ AlterRole(ParseState *pstate, AlterRoleStmt *stmt)
 	/*
 	 * Build an updated tuple, perusing the information just obtained
 	 */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-	MemSet(new_record_repl, false, sizeof(new_record_repl));
+	memset(new_record, 0, sizeof(new_record));
+	memset(new_record_nulls, false, sizeof(new_record_nulls));
+	memset(new_record_repl, false, sizeof(new_record_repl));
 
 	/*
 	 * issuper/createrole/etc
@@ -1500,9 +1500,9 @@ AddRoleMems(const char *rolename, Oid roleid,
 		}
 
 		/* Build a tuple to insert or update */
-		MemSet(new_record, 0, sizeof(new_record));
-		MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-		MemSet(new_record_repl, false, sizeof(new_record_repl));
+		memset(new_record, 0, sizeof(new_record));
+		memset(new_record_nulls, false, sizeof(new_record_nulls));
+		memset(new_record_repl, false, sizeof(new_record_repl));
 
 		new_record[Anum_pg_auth_members_roleid - 1] = ObjectIdGetDatum(roleid);
 		new_record[Anum_pg_auth_members_member - 1] = ObjectIdGetDatum(memberid);
@@ -1619,9 +1619,9 @@ DelRoleMems(const char *rolename, Oid roleid,
 			bool		new_record_repl[Natts_pg_auth_members];
 
 			/* Build a tuple to update with */
-			MemSet(new_record, 0, sizeof(new_record));
-			MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-			MemSet(new_record_repl, false, sizeof(new_record_repl));
+			memset(new_record, 0, sizeof(new_record));
+			memset(new_record_nulls, false, sizeof(new_record_nulls));
+			memset(new_record_repl, false, sizeof(new_record_repl));
 
 			new_record[Anum_pg_auth_members_admin_option - 1] = BoolGetDatum(false);
 			new_record_repl[Anum_pg_auth_members_admin_option - 1] = true;
diff --git a/src/backend/commands/vacuumparallel.c b/src/backend/commands/vacuumparallel.c
index 1753da6c83..6278a97106 100644
--- a/src/backend/commands/vacuumparallel.c
+++ b/src/backend/commands/vacuumparallel.c
@@ -352,7 +352,7 @@ parallel_vacuum_init(Relation rel, Relation *indrels, int nindexes,
 
 	/* Prepare shared information */
 	shared = (PVShared *) shm_toc_allocate(pcxt->toc, est_shared_len);
-	MemSet(shared, 0, est_shared_len);
+	memset(shared, 0, est_shared_len);
 	shared->relid = RelationGetRelid(rel);
 	shared->elevel = elevel;
 	shared->maintenance_work_mem_worker =
@@ -372,7 +372,7 @@ parallel_vacuum_init(Relation rel, Relation *indrels, int nindexes,
 												   est_dead_items_len);
 	dead_items->max_items = max_items;
 	dead_items->num_items = 0;
-	MemSet(dead_items->items, 0, sizeof(ItemPointerData) * max_items);
+	memset(dead_items->items, 0, sizeof(ItemPointerData) * max_items);
 	shm_toc_insert(pcxt->toc, PARALLEL_VACUUM_KEY_DEAD_ITEMS, dead_items);
 	pvs->dead_items = dead_items;
 
diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c
index ef2fd46092..6905edfa9e 100644
--- a/src/backend/executor/execMain.c
+++ b/src/backend/executor/execMain.c
@@ -1198,7 +1198,7 @@ InitResultRelInfo(ResultRelInfo *resultRelInfo,
 				  ResultRelInfo *partition_root_rri,
 				  int instrument_options)
 {
-	MemSet(resultRelInfo, 0, sizeof(ResultRelInfo));
+	memset(resultRelInfo, 0, sizeof(ResultRelInfo));
 	resultRelInfo->type = T_ResultRelInfo;
 	resultRelInfo->ri_RangeTableIndex = resultRelationIndex;
 	resultRelInfo->ri_RelationDesc = resultRelationDesc;
@@ -2735,7 +2735,7 @@ EvalPlanQualBegin(EPQState *epqstate)
 		Index		rtsize = parentestate->es_range_table_size;
 		PlanState  *rcplanstate = epqstate->recheckplanstate;
 
-		MemSet(epqstate->relsubs_done, 0, rtsize * sizeof(bool));
+		memset(epqstate->relsubs_done, 0, rtsize * sizeof(bool));
 
 		/* Recopy current values of parent parameters */
 		if (parentestate->es_plannedstmt->paramExecTypes != NIL)
diff --git a/src/backend/executor/execTuples.c b/src/backend/executor/execTuples.c
index 06ac253ea0..c29309a882 100644
--- a/src/backend/executor/execTuples.c
+++ b/src/backend/executor/execTuples.c
@@ -1587,7 +1587,7 @@ ExecStoreAllNullTuple(TupleTableSlot *slot)
 	/*
 	 * Fill all the columns of the virtual tuple with nulls
 	 */
-	MemSet(slot->tts_values, 0,
+	memset(slot->tts_values, 0,
 		   slot->tts_tupleDescriptor->natts * sizeof(Datum));
 	memset(slot->tts_isnull, true,
 		   slot->tts_tupleDescriptor->natts * sizeof(bool));
diff --git a/src/backend/executor/nodeAgg.c b/src/backend/executor/nodeAgg.c
index 139b2bd5f9..7768b0168e 100644
--- a/src/backend/executor/nodeAgg.c
+++ b/src/backend/executor/nodeAgg.c
@@ -2599,7 +2599,7 @@ agg_refill_hash_table(AggState *aggstate)
 	 * we rescan later. The expressions for sorted grouping sets will not be
 	 * evaluated after we recompile anyway.
 	 */
-	MemSet(aggstate->hash_pergroup, 0,
+	memset(aggstate->hash_pergroup, 0,
 		   sizeof(AggStatePerGroup) * aggstate->num_hashes);
 
 	/* free memory and reset hash tables */
@@ -4413,8 +4413,8 @@ ExecReScanAgg(AggState *node)
 	ExecClearTuple(node->ss.ss_ScanTupleSlot);
 
 	/* Forget current agg values */
-	MemSet(econtext->ecxt_aggvalues, 0, sizeof(Datum) * node->numaggs);
-	MemSet(econtext->ecxt_aggnulls, 0, sizeof(bool) * node->numaggs);
+	memset(econtext->ecxt_aggvalues, 0, sizeof(Datum) * node->numaggs);
+	memset(econtext->ecxt_aggnulls, 0, sizeof(bool) * node->numaggs);
 
 	/*
 	 * With AGG_HASHED/MIXED, the hash table is allocated in a sub-context of
@@ -4445,7 +4445,7 @@ ExecReScanAgg(AggState *node)
 		 */
 		for (setno = 0; setno < numGroupingSets; setno++)
 		{
-			MemSet(node->pergroups[setno], 0,
+			memset(node->pergroups[setno], 0,
 				   sizeof(AggStatePerGroupData) * node->numaggs);
 		}
 
diff --git a/src/backend/executor/nodeHash.c b/src/backend/executor/nodeHash.c
index 3510a4247c..f706b7510a 100644
--- a/src/backend/executor/nodeHash.c
+++ b/src/backend/executor/nodeHash.c
@@ -948,9 +948,9 @@ ExecHashIncreaseNumBatches(HashJoinTable hashtable)
 			repalloc(hashtable->innerBatchFile, nbatch * sizeof(BufFile *));
 		hashtable->outerBatchFile = (BufFile **)
 			repalloc(hashtable->outerBatchFile, nbatch * sizeof(BufFile *));
-		MemSet(hashtable->innerBatchFile + oldnbatch, 0,
+		memset(hashtable->innerBatchFile + oldnbatch, 0,
 			   (nbatch - oldnbatch) * sizeof(BufFile *));
-		MemSet(hashtable->outerBatchFile + oldnbatch, 0,
+		memset(hashtable->outerBatchFile + oldnbatch, 0,
 			   (nbatch - oldnbatch) * sizeof(BufFile *));
 	}
 
diff --git a/src/backend/executor/nodeIndexscan.c b/src/backend/executor/nodeIndexscan.c
index 5ef5c6930f..78774796a0 100644
--- a/src/backend/executor/nodeIndexscan.c
+++ b/src/backend/executor/nodeIndexscan.c
@@ -1437,7 +1437,7 @@ ExecIndexBuildScanKeys(PlanState *planstate, Relation index,
 			 * We don't use ScanKeyEntryInitialize for the header because it
 			 * isn't going to contain a valid sk_func pointer.
 			 */
-			MemSet(this_scan_key, 0, sizeof(ScanKeyData));
+			memset(this_scan_key, 0, sizeof(ScanKeyData));
 			this_scan_key->sk_flags = SK_ROW_HEADER;
 			this_scan_key->sk_attno = first_sub_key->sk_attno;
 			this_scan_key->sk_strategy = rc->rctype;
diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c
index 4b104c4d98..510f93f0b7 100644
--- a/src/backend/executor/nodeWindowAgg.c
+++ b/src/backend/executor/nodeWindowAgg.c
@@ -2723,8 +2723,8 @@ ExecReScanWindowAgg(WindowAggState *node)
 		ExecClearTuple(node->frametail_slot);
 
 	/* Forget current wfunc values */
-	MemSet(econtext->ecxt_aggvalues, 0, sizeof(Datum) * node->numfuncs);
-	MemSet(econtext->ecxt_aggnulls, 0, sizeof(bool) * node->numfuncs);
+	memset(econtext->ecxt_aggvalues, 0, sizeof(Datum) * node->numfuncs);
+	memset(econtext->ecxt_aggnulls, 0, sizeof(bool) * node->numfuncs);
 
 	/*
 	 * if chgParam of subnode is not null then plan will be re-scanned by
diff --git a/src/backend/libpq/auth.c b/src/backend/libpq/auth.c
index efc53f3135..7c4494c064 100644
--- a/src/backend/libpq/auth.c
+++ b/src/backend/libpq/auth.c
@@ -3041,7 +3041,7 @@ PerformRadiusTransaction(const char *server, const char *secret, const char *por
 	if (identifier == NULL)
 		identifier = "postgresql";
 
-	MemSet(&hint, 0, sizeof(hint));
+	memset(&hint, 0, sizeof(hint));
 	hint.ai_socktype = SOCK_DGRAM;
 	hint.ai_family = AF_UNSPEC;
 	port = atoi(portstr);
diff --git a/src/backend/libpq/be-fsstubs.c b/src/backend/libpq/be-fsstubs.c
index 5804532881..fc4811aa8a 100644
--- a/src/backend/libpq/be-fsstubs.c
+++ b/src/backend/libpq/be-fsstubs.c
@@ -688,7 +688,7 @@ newLOfd(void)
 		newsize = cookies_size * 2;
 		cookies = (LargeObjectDesc **)
 			repalloc(cookies, newsize * sizeof(LargeObjectDesc *));
-		MemSet(cookies + cookies_size, 0,
+		memset(cookies + cookies_size, 0,
 			   (newsize - cookies_size) * sizeof(LargeObjectDesc *));
 		cookies_size = newsize;
 	}
diff --git a/src/backend/libpq/hba.c b/src/backend/libpq/hba.c
index 327a4b42af..30fd58e4ca 100644
--- a/src/backend/libpq/hba.c
+++ b/src/backend/libpq/hba.c
@@ -1964,7 +1964,7 @@ parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline,
 		/* For each entry in the list, translate it */
 		foreach(l, parsed_servers)
 		{
-			MemSet(&hints, 0, sizeof(hints));
+			memset(&hints, 0, sizeof(hints));
 			hints.ai_socktype = SOCK_DGRAM;
 			hints.ai_family = AF_UNSPEC;
 
diff --git a/src/backend/libpq/pqcomm.c b/src/backend/libpq/pqcomm.c
index 75392a8bb7..f75304cea1 100644
--- a/src/backend/libpq/pqcomm.c
+++ b/src/backend/libpq/pqcomm.c
@@ -343,7 +343,7 @@ StreamServerPort(int family, const char *hostName, unsigned short portNumber,
 #endif
 
 	/* Initialize hint structure */
-	MemSet(&hint, 0, sizeof(hint));
+	memset(&hint, 0, sizeof(hint));
 	hint.ai_family = family;
 	hint.ai_flags = AI_PASSIVE;
 	hint.ai_socktype = SOCK_STREAM;
diff --git a/src/backend/libpq/pqmq.c b/src/backend/libpq/pqmq.c
index 4d0415e379..139bb90dc5 100644
--- a/src/backend/libpq/pqmq.c
+++ b/src/backend/libpq/pqmq.c
@@ -204,7 +204,7 @@ void
 pq_parse_errornotice(StringInfo msg, ErrorData *edata)
 {
 	/* Initialize edata with reasonable defaults. */
-	MemSet(edata, 0, sizeof(ErrorData));
+	memset(edata, 0, sizeof(ErrorData));
 	edata->elevel = ERROR;
 	edata->assoc_context = CurrentMemoryContext;
 
diff --git a/src/backend/nodes/tidbitmap.c b/src/backend/nodes/tidbitmap.c
index a7a6b26668..dd0260512d 100644
--- a/src/backend/nodes/tidbitmap.c
+++ b/src/backend/nodes/tidbitmap.c
@@ -1230,7 +1230,7 @@ tbm_get_pageentry(TIDBitmap *tbm, BlockNumber pageno)
 	{
 		char		oldstatus = page->status;
 
-		MemSet(page, 0, sizeof(PagetableEntry));
+		memset(page, 0, sizeof(PagetableEntry));
 		page->status = oldstatus;
 		page->blockno = pageno;
 		/* must count it too */
@@ -1317,7 +1317,7 @@ tbm_mark_page_lossy(TIDBitmap *tbm, BlockNumber pageno)
 	{
 		char		oldstatus = page->status;
 
-		MemSet(page, 0, sizeof(PagetableEntry));
+		memset(page, 0, sizeof(PagetableEntry));
 		page->status = oldstatus;
 		page->blockno = chunk_pageno;
 		page->ischunk = true;
@@ -1330,7 +1330,7 @@ tbm_mark_page_lossy(TIDBitmap *tbm, BlockNumber pageno)
 		char		oldstatus = page->status;
 
 		/* chunk header page was formerly non-lossy, make it lossy */
-		MemSet(page, 0, sizeof(PagetableEntry));
+		memset(page, 0, sizeof(PagetableEntry));
 		page->status = oldstatus;
 		page->blockno = chunk_pageno;
 		page->ischunk = true;
diff --git a/src/backend/optimizer/path/costsize.c b/src/backend/optimizer/path/costsize.c
index ed98ba7dbd..d2da6e5f0a 100644
--- a/src/backend/optimizer/path/costsize.c
+++ b/src/backend/optimizer/path/costsize.c
@@ -2905,7 +2905,7 @@ cost_agg(Path *path, PlannerInfo *root,
 	if (aggcosts == NULL)
 	{
 		Assert(aggstrategy == AGG_HASHED);
-		MemSet(&dummy_aggcosts, 0, sizeof(AggClauseCosts));
+		memset(&dummy_aggcosts, 0, sizeof(AggClauseCosts));
 		aggcosts = &dummy_aggcosts;
 	}
 
diff --git a/src/backend/optimizer/path/indxpath.c b/src/backend/optimizer/path/indxpath.c
index 0ef70ad7f1..f6c2cd8974 100644
--- a/src/backend/optimizer/path/indxpath.c
+++ b/src/backend/optimizer/path/indxpath.c
@@ -269,7 +269,7 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
 		/*
 		 * Identify the restriction clauses that can match the index.
 		 */
-		MemSet(&rclauseset, 0, sizeof(rclauseset));
+		memset(&rclauseset, 0, sizeof(rclauseset));
 		match_restriction_clauses_to_index(root, index, &rclauseset);
 
 		/*
@@ -286,7 +286,7 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
 		 * step finds only "loose" join clauses that have not been merged into
 		 * EquivalenceClasses.  Also, collect join OR clauses for later.
 		 */
-		MemSet(&jclauseset, 0, sizeof(jclauseset));
+		memset(&jclauseset, 0, sizeof(jclauseset));
 		match_join_clauses_to_index(root, rel, index,
 									&jclauseset, &joinorclauses);
 
@@ -294,7 +294,7 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
 		 * Look for EquivalenceClasses that can generate joinclauses matching
 		 * the index.
 		 */
-		MemSet(&eclauseset, 0, sizeof(eclauseset));
+		memset(&eclauseset, 0, sizeof(eclauseset));
 		match_eclass_clauses_to_index(root, index,
 									  &eclauseset);
 
@@ -616,7 +616,7 @@ get_join_index_paths(PlannerInfo *root, RelOptInfo *rel,
 		return;
 
 	/* Identify indexclauses usable with this relids set */
-	MemSet(&clauseset, 0, sizeof(clauseset));
+	memset(&clauseset, 0, sizeof(clauseset));
 
 	for (indexcol = 0; indexcol < index->nkeycolumns; indexcol++)
 	{
@@ -1211,7 +1211,7 @@ build_paths_for_OR(PlannerInfo *root, RelOptInfo *rel,
 		/*
 		 * Identify the restriction clauses that can match the index.
 		 */
-		MemSet(&clauseset, 0, sizeof(clauseset));
+		memset(&clauseset, 0, sizeof(clauseset));
 		match_clauses_to_index(root, clauses, index, &clauseset);
 
 		/*
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c
index a0f2390334..340e902a15 100644
--- a/src/backend/optimizer/plan/planner.c
+++ b/src/backend/optimizer/plan/planner.c
@@ -3352,7 +3352,7 @@ create_grouping_paths(PlannerInfo *root,
 	RelOptInfo *partially_grouped_rel;
 	AggClauseCosts agg_costs;
 
-	MemSet(&agg_costs, 0, sizeof(AggClauseCosts));
+	memset(&agg_costs, 0, sizeof(AggClauseCosts));
 	get_agg_clause_costs(root, AGGSPLIT_SIMPLE, &agg_costs);
 
 	/*
@@ -5915,12 +5915,12 @@ expression_planner_with_deps(Expr *expr,
 	PlannerInfo root;
 
 	/* Make up dummy planner state so we can use setrefs machinery */
-	MemSet(&glob, 0, sizeof(glob));
+	memset(&glob, 0, sizeof(glob));
 	glob.type = T_PlannerGlobal;
 	glob.relationOids = NIL;
 	glob.invalItems = NIL;
 
-	MemSet(&root, 0, sizeof(root));
+	memset(&root, 0, sizeof(root));
 	root.type = T_PlannerInfo;
 	root.glob = &glob;
 
@@ -6688,8 +6688,8 @@ create_partial_grouping_paths(PlannerInfo *root,
 		 * Collect statistics about aggregates for estimating costs of
 		 * performing aggregation in parallel.
 		 */
-		MemSet(agg_partial_costs, 0, sizeof(AggClauseCosts));
-		MemSet(agg_final_costs, 0, sizeof(AggClauseCosts));
+		memset(agg_partial_costs, 0, sizeof(AggClauseCosts));
+		memset(agg_final_costs, 0, sizeof(AggClauseCosts));
 		if (parse->hasAggs)
 		{
 			/* partial phase */
diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c
index d95fd89807..3cb86fdba0 100644
--- a/src/backend/optimizer/plan/setrefs.c
+++ b/src/backend/optimizer/plan/setrefs.c
@@ -3274,14 +3274,14 @@ extract_query_dependencies(Node *query,
 	PlannerInfo root;
 
 	/* Make up dummy planner state so we can use this module's machinery */
-	MemSet(&glob, 0, sizeof(glob));
+	memset(&glob, 0, sizeof(glob));
 	glob.type = T_PlannerGlobal;
 	glob.relationOids = NIL;
 	glob.invalItems = NIL;
 	/* Hack: we use glob.dependsOnRole to collect hasRowSecurity flags */
 	glob.dependsOnRole = false;
 
-	MemSet(&root, 0, sizeof(root));
+	memset(&root, 0, sizeof(root));
 	root.type = T_PlannerInfo;
 	root.glob = &glob;
 
diff --git a/src/backend/optimizer/util/relnode.c b/src/backend/optimizer/util/relnode.c
index 520409f4ba..9ebe594fcb 100644
--- a/src/backend/optimizer/util/relnode.c
+++ b/src/backend/optimizer/util/relnode.c
@@ -160,13 +160,13 @@ expand_planner_arrays(PlannerInfo *root, int add_size)
 	root->simple_rel_array = (RelOptInfo **)
 		repalloc(root->simple_rel_array,
 				 sizeof(RelOptInfo *) * new_size);
-	MemSet(root->simple_rel_array + root->simple_rel_array_size,
+	memset(root->simple_rel_array + root->simple_rel_array_size,
 		   0, sizeof(RelOptInfo *) * add_size);
 
 	root->simple_rte_array = (RangeTblEntry **)
 		repalloc(root->simple_rte_array,
 				 sizeof(RangeTblEntry *) * new_size);
-	MemSet(root->simple_rte_array + root->simple_rel_array_size,
+	memset(root->simple_rte_array + root->simple_rel_array_size,
 		   0, sizeof(RangeTblEntry *) * add_size);
 
 	if (root->append_rel_array)
@@ -174,7 +174,7 @@ expand_planner_arrays(PlannerInfo *root, int add_size)
 		root->append_rel_array = (AppendRelInfo **)
 			repalloc(root->append_rel_array,
 					 sizeof(AppendRelInfo *) * new_size);
-		MemSet(root->append_rel_array + root->simple_rel_array_size,
+		memset(root->append_rel_array + root->simple_rel_array_size,
 			   0, sizeof(AppendRelInfo *) * add_size);
 	}
 	else
diff --git a/src/backend/parser/parse_oper.c b/src/backend/parser/parse_oper.c
index cf64afbd85..084d45e7e1 100644
--- a/src/backend/parser/parse_oper.c
+++ b/src/backend/parser/parse_oper.c
@@ -958,7 +958,7 @@ make_oper_cache_key(ParseState *pstate, OprCacheKey *key, List *opname,
 	DeconstructQualifiedName(opname, &schemaname, &opername);
 
 	/* ensure zero-fill for stable hashing */
-	MemSet(key, 0, sizeof(OprCacheKey));
+	memset(key, 0, sizeof(OprCacheKey));
 
 	/* save operator name and input types into key */
 	strlcpy(key->oprname, opername, NAMEDATALEN);
diff --git a/src/backend/parser/parse_param.c b/src/backend/parser/parse_param.c
index f668abfcb3..03f022d6c9 100644
--- a/src/backend/parser/parse_param.c
+++ b/src/backend/parser/parse_param.c
@@ -150,7 +150,7 @@ variable_paramref_hook(ParseState *pstate, ParamRef *pref)
 		else
 			*parstate->paramTypes = (Oid *) palloc(paramno * sizeof(Oid));
 		/* Zero out the previously-unreferenced slots */
-		MemSet(*parstate->paramTypes + *parstate->numParams,
+		memset(*parstate->paramTypes + *parstate->numParams,
 			   0,
 			   (paramno - *parstate->numParams) * sizeof(Oid));
 		*parstate->numParams = paramno;
diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c
index 2a1d44b813..cb3b64afde 100644
--- a/src/backend/parser/parse_target.c
+++ b/src/backend/parser/parse_target.c
@@ -1596,7 +1596,7 @@ expandRecordVariable(ParseState *pstate, Var *var, int levelsup)
 					 */
 					ParseState	mypstate;
 
-					MemSet(&mypstate, 0, sizeof(mypstate));
+					memset(&mypstate, 0, sizeof(mypstate));
 					mypstate.parentParseState = pstate;
 					mypstate.p_rtable = rte->subquery->rtable;
 					/* don't bother filling the rest of the fake pstate */
@@ -1652,7 +1652,7 @@ expandRecordVariable(ParseState *pstate, Var *var, int levelsup)
 					ParseState	mypstate;
 					Index		levelsup;
 
-					MemSet(&mypstate, 0, sizeof(mypstate));
+					memset(&mypstate, 0, sizeof(mypstate));
 					/* this loop must work, since GetCTEForRTE did */
 					for (levelsup = 0;
 						 levelsup < rte->ctelevelsup + netlevelsup;
diff --git a/src/backend/port/win32/timer.c b/src/backend/port/win32/timer.c
index 3405253af3..67a434ab9e 100644
--- a/src/backend/port/win32/timer.c
+++ b/src/backend/port/win32/timer.c
@@ -98,7 +98,7 @@ setitimer(int which, const struct itimerval *value, struct itimerval *ovalue)
 					(errmsg_internal("could not create timer event: error code %lu",
 									 GetLastError())));
 
-		MemSet(&timerCommArea.value, 0, sizeof(struct itimerval));
+		memset(&timerCommArea.value, 0, sizeof(struct itimerval));
 
 		InitializeCriticalSection(&timerCommArea.crit_sec);
 
diff --git a/src/backend/postmaster/checkpointer.c b/src/backend/postmaster/checkpointer.c
index c937c39f50..02b1d2533e 100644
--- a/src/backend/postmaster/checkpointer.c
+++ b/src/backend/postmaster/checkpointer.c
@@ -902,7 +902,7 @@ CheckpointerShmemInit(void)
 		 * requests array; this is so that CompactCheckpointerRequestQueue can
 		 * assume that any pad bytes in the request structs are zeroes.
 		 */
-		MemSet(CheckpointerShmem, 0, size);
+		memset(CheckpointerShmem, 0, size);
 		SpinLockInit(&CheckpointerShmem->ckpt_lck);
 		CheckpointerShmem->max_requests = NBuffers;
 		ConditionVariableInit(&CheckpointerShmem->start_cv);
diff --git a/src/backend/postmaster/pgarch.c b/src/backend/postmaster/pgarch.c
index 25e31c42e1..bd673df1b0 100644
--- a/src/backend/postmaster/pgarch.c
+++ b/src/backend/postmaster/pgarch.c
@@ -169,7 +169,7 @@ PgArchShmemInit(void)
 	if (!found)
 	{
 		/* First time through, so initialize */
-		MemSet(PgArch, 0, PgArchShmemSize());
+		memset(PgArch, 0, PgArchShmemSize());
 		PgArch->pgprocno = INVALID_PGPROCNO;
 		SpinLockInit(&PgArch->arch_lck);
 	}
diff --git a/src/backend/replication/basebackup.c b/src/backend/replication/basebackup.c
index 5244823ff8..ce53e628b6 100644
--- a/src/backend/replication/basebackup.c
+++ b/src/backend/replication/basebackup.c
@@ -688,7 +688,7 @@ parse_basebackup_options(List *options, basebackup_options *opt)
 	bool		o_compression_detail = false;
 	char	   *compression_detail_str = NULL;
 
-	MemSet(opt, 0, sizeof(*opt));
+	memset(opt, 0, sizeof(*opt));
 	opt->manifest = MANIFEST_OPTION_NO;
 	opt->manifest_checksum_type = CHECKSUM_TYPE_CRC32C;
 	opt->compression = PG_COMPRESSION_NONE;
@@ -1687,7 +1687,7 @@ sendFile(bbsink *sink, const char *readfilename, const char *tarfilename,
 		size_t		remaining = statbuf->st_size - len;
 		size_t		nbytes = Min(sink->bbs_buffer_length, remaining);
 
-		MemSet(sink->bbs_buffer, 0, nbytes);
+		memset(sink->bbs_buffer, 0, nbytes);
 		if (pg_checksum_update(&checksum_ctx,
 							   (uint8 *) sink->bbs_buffer,
 							   nbytes) < 0)
@@ -1790,7 +1790,7 @@ _tarWritePadding(bbsink *sink, int len)
 
 	if (pad > 0)
 	{
-		MemSet(sink->bbs_buffer, 0, pad);
+		memset(sink->bbs_buffer, 0, pad);
 		bbsink_archive_contents(sink, pad);
 	}
 }
diff --git a/src/backend/replication/logical/launcher.c b/src/backend/replication/logical/launcher.c
index bd5f78cf9a..4c4ad80f9a 100644
--- a/src/backend/replication/logical/launcher.c
+++ b/src/backend/replication/logical/launcher.c
@@ -953,8 +953,8 @@ pg_stat_get_subscription(PG_FUNCTION_ARGS)
 
 		worker_pid = worker.proc->pid;
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
+		memset(values, 0, sizeof(values));
+		memset(nulls, 0, sizeof(nulls));
 
 		values[0] = ObjectIdGetDatum(worker.subid);
 		if (OidIsValid(worker.relid))
diff --git a/src/backend/replication/logical/origin.c b/src/backend/replication/logical/origin.c
index 21937ab2d3..f5cb766f66 100644
--- a/src/backend/replication/logical/origin.c
+++ b/src/backend/replication/logical/origin.c
@@ -524,7 +524,7 @@ ReplicationOriginShmemInit(void)
 	{
 		int			i;
 
-		MemSet(replication_states_ctl, 0, ReplicationOriginShmemSize());
+		memset(replication_states_ctl, 0, ReplicationOriginShmemSize());
 
 		replication_states_ctl->tranche_id = LWTRANCHE_REPLICATION_ORIGIN_STATE;
 
diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c
index e5c2102bcd..7071d04aaa 100644
--- a/src/backend/replication/slot.c
+++ b/src/backend/replication/slot.c
@@ -147,7 +147,7 @@ ReplicationSlotsShmemInit(void)
 		int			i;
 
 		/* First time through, so initialize */
-		MemSet(ReplicationSlotCtl, 0, ReplicationSlotsShmemSize());
+		memset(ReplicationSlotCtl, 0, ReplicationSlotsShmemSize());
 
 		for (i = 0; i < max_replication_slots; i++)
 		{
diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index 9452932d59..3d37c1fe62 100644
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -1410,7 +1410,7 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 		 * see details. Other users only get the pid value to know whether it
 		 * is a WAL receiver, but no details.
 		 */
-		MemSet(&nulls[1], true, sizeof(bool) * (tupdesc->natts - 1));
+		memset(&nulls[1], true, sizeof(bool) * (tupdesc->natts - 1));
 	}
 	else
 	{
diff --git a/src/backend/replication/walreceiverfuncs.c b/src/backend/replication/walreceiverfuncs.c
index 90798b9d53..3e4ac0788e 100644
--- a/src/backend/replication/walreceiverfuncs.c
+++ b/src/backend/replication/walreceiverfuncs.c
@@ -62,7 +62,7 @@ WalRcvShmemInit(void)
 	if (!found)
 	{
 		/* First time through, so initialize */
-		MemSet(WalRcv, 0, WalRcvShmemSize());
+		memset(WalRcv, 0, WalRcvShmemSize());
 		WalRcv->walRcvState = WALRCV_STOPPED;
 		ConditionVariableInit(&WalRcv->walRcvStoppedCV);
 		SpinLockInit(&WalRcv->mutex);
diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c
index e42671722a..800a831c69 100644
--- a/src/backend/replication/walsender.c
+++ b/src/backend/replication/walsender.c
@@ -437,7 +437,7 @@ IdentifySystem(void)
 	}
 
 	dest = CreateDestReceiver(DestRemoteSimple);
-	MemSet(nulls, false, sizeof(nulls));
+	memset(nulls, false, sizeof(nulls));
 
 	/* need a tuple descriptor representing four columns */
 	tupdesc = CreateTemplateTupleDesc(4);
@@ -495,8 +495,8 @@ ReadReplicationSlot(ReadReplicationSlotCmd *cmd)
 	TupleDescInitBuiltinEntry(tupdesc, (AttrNumber) 3, "restart_tli",
 							  INT8OID, -1, 0);
 
-	MemSet(values, 0, READ_REPLICATION_SLOT_COLS * sizeof(Datum));
-	MemSet(nulls, true, READ_REPLICATION_SLOT_COLS * sizeof(bool));
+	memset(values, 0, READ_REPLICATION_SLOT_COLS * sizeof(Datum));
+	memset(nulls, true, READ_REPLICATION_SLOT_COLS * sizeof(bool));
 
 	LWLockAcquire(ReplicationSlotControlLock, LW_SHARED);
 	slot = SearchNamedReplicationSlot(cmd->slotname, false);
@@ -878,7 +878,7 @@ StartReplication(StartReplicationCmd *cmd)
 				 LSN_FORMAT_ARGS(sendTimeLineValidUpto));
 
 		dest = CreateDestReceiver(DestRemoteSimple);
-		MemSet(nulls, false, sizeof(nulls));
+		memset(nulls, false, sizeof(nulls));
 
 		/*
 		 * Need a tuple descriptor representing two columns. int8 may seem
@@ -1191,7 +1191,7 @@ CreateReplicationSlot(CreateReplicationSlotCmd *cmd)
 			 LSN_FORMAT_ARGS(MyReplicationSlot->data.confirmed_flush));
 
 	dest = CreateDestReceiver(DestRemoteSimple);
-	MemSet(nulls, false, sizeof(nulls));
+	memset(nulls, false, sizeof(nulls));
 
 	/*----------
 	 * Need a tuple descriptor representing four columns:
@@ -3285,7 +3285,7 @@ WalSndShmemInit(void)
 	if (!found)
 	{
 		/* First time through, so initialize */
-		MemSet(WalSndCtl, 0, WalSndShmemSize());
+		memset(WalSndCtl, 0, WalSndShmemSize());
 
 		for (i = 0; i < NUM_SYNC_REP_WAIT_MODE; i++)
 			SHMQueueInit(&(WalSndCtl->SyncRepQueue[i]));
@@ -3550,7 +3550,7 @@ pg_stat_get_wal_senders(PG_FUNCTION_ARGS)
 			 * can see details. Other users only get the pid value to know
 			 * it's a walsender, but no details.
 			 */
-			MemSet(&nulls[1], true, PG_STAT_GET_WAL_SENDERS_COLS - 1);
+			memset(&nulls[1], true, PG_STAT_GET_WAL_SENDERS_COLS - 1);
 		}
 		else
 		{
diff --git a/src/backend/rewrite/rewriteDefine.c b/src/backend/rewrite/rewriteDefine.c
index 185bf5fbff..862aafeab7 100644
--- a/src/backend/rewrite/rewriteDefine.c
+++ b/src/backend/rewrite/rewriteDefine.c
@@ -81,7 +81,7 @@ InsertRule(const char *rulname,
 	/*
 	 * Set up *nulls and *values arrays
 	 */
-	MemSet(nulls, false, sizeof(nulls));
+	memset(nulls, false, sizeof(nulls));
 
 	namestrcpy(&rname, rulname);
 	values[Anum_pg_rewrite_rulename - 1] = NameGetDatum(&rname);
@@ -115,7 +115,7 @@ InsertRule(const char *rulname,
 		/*
 		 * When replacing, we don't need to replace every attribute
 		 */
-		MemSet(replaces, false, sizeof(replaces));
+		memset(replaces, false, sizeof(replaces));
 		replaces[Anum_pg_rewrite_ev_type - 1] = true;
 		replaces[Anum_pg_rewrite_is_instead - 1] = true;
 		replaces[Anum_pg_rewrite_ev_qual - 1] = true;
diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index ae13011d27..eecf64aa98 100644
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -981,7 +981,7 @@ ReadBuffer_common(SMgrRelation smgr, char relpersistence, ForkNumber forkNum,
 	if (isExtend)
 	{
 		/* new buffers are zero-filled */
-		MemSet((char *) bufBlock, 0, BLCKSZ);
+		memset((char *) bufBlock, 0, BLCKSZ);
 		/* don't set checksum for all-zero page */
 		smgrextend(smgr, forkNum, blockNum, (char *) bufBlock, false);
 
@@ -999,7 +999,7 @@ ReadBuffer_common(SMgrRelation smgr, char relpersistence, ForkNumber forkNum,
 		 * just wants us to allocate a buffer.
 		 */
 		if (mode == RBM_ZERO_AND_LOCK || mode == RBM_ZERO_AND_CLEANUP_LOCK)
-			MemSet((char *) bufBlock, 0, BLCKSZ);
+			memset((char *) bufBlock, 0, BLCKSZ);
 		else
 		{
 			instr_time	io_start,
@@ -1029,7 +1029,7 @@ ReadBuffer_common(SMgrRelation smgr, char relpersistence, ForkNumber forkNum,
 							 errmsg("invalid page in block %u of relation %s; zeroing out page",
 									blockNum,
 									relpath(smgr->smgr_rnode, forkNum))));
-					MemSet((char *) bufBlock, 0, BLCKSZ);
+					memset((char *) bufBlock, 0, BLCKSZ);
 				}
 				else
 					ereport(ERROR,
diff --git a/src/backend/storage/file/fd.c b/src/backend/storage/file/fd.c
index 24704b6a02..b13cbd18ae 100644
--- a/src/backend/storage/file/fd.c
+++ b/src/backend/storage/file/fd.c
@@ -891,7 +891,7 @@ InitFileAccess(void)
 				(errcode(ERRCODE_OUT_OF_MEMORY),
 				 errmsg("out of memory")));
 
-	MemSet((char *) &(VfdCache[0]), 0, sizeof(Vfd));
+	memset((char *) &(VfdCache[0]), 0, sizeof(Vfd));
 	VfdCache->fd = VFD_CLOSED;
 
 	SizeVfdCache = 1;
@@ -1439,7 +1439,7 @@ AllocateVfd(void)
 		 */
 		for (i = SizeVfdCache; i < newCacheSize; i++)
 		{
-			MemSet((char *) &(VfdCache[i]), 0, sizeof(Vfd));
+			memset((char *) &(VfdCache[i]), 0, sizeof(Vfd));
 			VfdCache[i].nextFree = i + 1;
 			VfdCache[i].fd = VFD_CLOSED;
 		}
diff --git a/src/backend/storage/ipc/pmsignal.c b/src/backend/storage/ipc/pmsignal.c
index 1c668d183c..b8d40ad5f7 100644
--- a/src/backend/storage/ipc/pmsignal.c
+++ b/src/backend/storage/ipc/pmsignal.c
@@ -141,7 +141,7 @@ PMSignalShmemInit(void)
 	if (!found)
 	{
 		/* initialize all flags to zeroes */
-		MemSet(unvolatize(PMSignalData *, PMSignalState), 0, PMSignalShmemSize());
+		memset(unvolatize(PMSignalData *, PMSignalState), 0, PMSignalShmemSize());
 		PMSignalState->num_child_flags = MaxLivePostmasterChildren();
 	}
 }
diff --git a/src/backend/storage/ipc/procsignal.c b/src/backend/storage/ipc/procsignal.c
index 21a9fc0fdd..ac5fcdc6ed 100644
--- a/src/backend/storage/ipc/procsignal.c
+++ b/src/backend/storage/ipc/procsignal.c
@@ -142,7 +142,7 @@ ProcSignalShmemInit(void)
 			ProcSignalSlot *slot = &ProcSignal->psh_slot[i];
 
 			slot->pss_pid = 0;
-			MemSet(slot->pss_signalFlags, 0, sizeof(slot->pss_signalFlags));
+			memset(slot->pss_signalFlags, 0, sizeof(slot->pss_signalFlags));
 			pg_atomic_init_u64(&slot->pss_barrierGeneration, PG_UINT64_MAX);
 			pg_atomic_init_u32(&slot->pss_barrierCheckMask, 0);
 			ConditionVariableInit(&slot->pss_barrierCV);
@@ -173,7 +173,7 @@ ProcSignalInit(int pss_idx)
 			 MyProcPid, pss_idx);
 
 	/* Clear out any leftover signal reasons */
-	MemSet(slot->pss_signalFlags, 0, NUM_PROCSIGNALS * sizeof(sig_atomic_t));
+	memset(slot->pss_signalFlags, 0, NUM_PROCSIGNALS * sizeof(sig_atomic_t));
 
 	/*
 	 * Initialize barrier state. Since we're a brand-new process, there
diff --git a/src/backend/storage/large_object/inv_api.c b/src/backend/storage/large_object/inv_api.c
index d204482a61..bf5016bbbf 100644
--- a/src/backend/storage/large_object/inv_api.c
+++ b/src/backend/storage/large_object/inv_api.c
@@ -546,7 +546,7 @@ inv_read(LargeObjectDesc *obj_desc, char *buf, int nbytes)
 		{
 			n = pageoff - obj_desc->offset;
 			n = (n <= (nbytes - nread)) ? n : (nbytes - nread);
-			MemSet(buf + nread, 0, n);
+			memset(buf + nread, 0, n);
 			nread += n;
 			obj_desc->offset += n;
 		}
@@ -689,7 +689,7 @@ inv_write(LargeObjectDesc *obj_desc, const char *buf, int nbytes)
 			 */
 			off = (int) (obj_desc->offset % LOBLKSIZE);
 			if (off > len)
-				MemSet(workb + len, 0, off - len);
+				memset(workb + len, 0, off - len);
 
 			/*
 			 * Insert appropriate portion of new data
@@ -734,7 +734,7 @@ inv_write(LargeObjectDesc *obj_desc, const char *buf, int nbytes)
 			 */
 			off = (int) (obj_desc->offset % LOBLKSIZE);
 			if (off > 0)
-				MemSet(workb, 0, off);
+				memset(workb, 0, off);
 
 			/*
 			 * Insert appropriate portion of new data
@@ -874,7 +874,7 @@ inv_truncate(LargeObjectDesc *obj_desc, int64 len)
 		 */
 		off = len % LOBLKSIZE;
 		if (off > pagelen)
-			MemSet(workb + pagelen, 0, off - pagelen);
+			memset(workb + pagelen, 0, off - pagelen);
 
 		/* compute length of new page */
 		SET_VARSIZE(&workbuf.hdr, off + VARHDRSZ);
@@ -913,7 +913,7 @@ inv_truncate(LargeObjectDesc *obj_desc, int64 len)
 		 */
 		off = len % LOBLKSIZE;
 		if (off > 0)
-			MemSet(workb, 0, off);
+			memset(workb, 0, off);
 
 		/* compute length of new page */
 		SET_VARSIZE(&workbuf.hdr, off + VARHDRSZ);
diff --git a/src/backend/storage/lmgr/deadlock.c b/src/backend/storage/lmgr/deadlock.c
index cd9c0418ec..6c6c1eb167 100644
--- a/src/backend/storage/lmgr/deadlock.c
+++ b/src/backend/storage/lmgr/deadlock.c
@@ -918,8 +918,8 @@ TopoSort(LOCK *lock,
 	 * present.  If so, the constraint is relevant to this wait queue; if not,
 	 * it isn't.
 	 */
-	MemSet(beforeConstraints, 0, queue_size * sizeof(int));
-	MemSet(afterConstraints, 0, queue_size * sizeof(int));
+	memset(beforeConstraints, 0, queue_size * sizeof(int));
+	memset(afterConstraints, 0, queue_size * sizeof(int));
 	for (i = 0; i < nConstraints; i++)
 	{
 		/*
diff --git a/src/backend/storage/lmgr/lock.c b/src/backend/storage/lmgr/lock.c
index 5f5803f681..ec2ea6c42e 100644
--- a/src/backend/storage/lmgr/lock.c
+++ b/src/backend/storage/lmgr/lock.c
@@ -603,7 +603,7 @@ LockHeldByMe(const LOCKTAG *locktag, LOCKMODE lockmode)
 	/*
 	 * See if there is a LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
+	memset(&localtag, 0, sizeof(localtag)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
@@ -658,7 +658,7 @@ LockHasWaiters(const LOCKTAG *locktag, LOCKMODE lockmode, bool sessionLock)
 	/*
 	 * Find the LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
+	memset(&localtag, 0, sizeof(localtag)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
@@ -820,7 +820,7 @@ LockAcquireExtended(const LOCKTAG *locktag,
 	/*
 	 * Find or create a LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
+	memset(&localtag, 0, sizeof(localtag)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
@@ -1198,8 +1198,8 @@ SetupLockInTable(LockMethod lockMethodTable, PGPROC *proc,
 		ProcQueueInit(&(lock->waitProcs));
 		lock->nRequested = 0;
 		lock->nGranted = 0;
-		MemSet(lock->requested, 0, sizeof(int) * MAX_LOCKMODES);
-		MemSet(lock->granted, 0, sizeof(int) * MAX_LOCKMODES);
+		memset(lock->requested, 0, sizeof(int) * MAX_LOCKMODES);
+		memset(lock->granted, 0, sizeof(int) * MAX_LOCKMODES);
 		LOCK_PRINT("LockAcquire: new", lock, lockmode);
 	}
 	else
@@ -1999,7 +1999,7 @@ LockRelease(const LOCKTAG *locktag, LOCKMODE lockmode, bool sessionLock)
 	/*
 	 * Find the LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
+	memset(&localtag, 0, sizeof(localtag)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
@@ -4271,8 +4271,8 @@ lock_twophase_recover(TransactionId xid, uint16 info,
 		ProcQueueInit(&(lock->waitProcs));
 		lock->nRequested = 0;
 		lock->nGranted = 0;
-		MemSet(lock->requested, 0, sizeof(int) * MAX_LOCKMODES);
-		MemSet(lock->granted, 0, sizeof(int) * MAX_LOCKMODES);
+		memset(lock->requested, 0, sizeof(int) * MAX_LOCKMODES);
+		memset(lock->granted, 0, sizeof(int) * MAX_LOCKMODES);
 		LOCK_PRINT("lock_twophase_recover: new", lock, lockmode);
 	}
 	else
diff --git a/src/backend/storage/lmgr/lwlock.c b/src/backend/storage/lmgr/lwlock.c
index 8aef909037..c09b127cf6 100644
--- a/src/backend/storage/lmgr/lwlock.c
+++ b/src/backend/storage/lmgr/lwlock.c
@@ -397,7 +397,7 @@ get_lwlock_stats_entry(LWLock *lock)
 		return &lwlock_stats_dummy;
 
 	/* Fetch or create the entry. */
-	MemSet(&key, 0, sizeof(key));
+	memset(&key, 0, sizeof(key));
 	key.tranche = lock->tranche;
 	key.instance = lock;
 	lwstats = hash_search(lwlock_stats_htab, &key, HASH_ENTER, &found);
diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c
index 37aaab1338..e732d61220 100644
--- a/src/backend/storage/lmgr/proc.c
+++ b/src/backend/storage/lmgr/proc.c
@@ -192,7 +192,7 @@ InitProcGlobal(void)
 	 * between groups.
 	 */
 	procs = (PGPROC *) ShmemAlloc(TotalProcs * sizeof(PGPROC));
-	MemSet(procs, 0, TotalProcs * sizeof(PGPROC));
+	memset(procs, 0, TotalProcs * sizeof(PGPROC));
 	ProcGlobal->allProcs = procs;
 	/* XXX allProcCount isn't really all of them; it excludes prepared xacts */
 	ProcGlobal->allProcCount = MaxBackends + NUM_AUXILIARY_PROCS;
@@ -206,11 +206,11 @@ InitProcGlobal(void)
 	 */
 	ProcGlobal->xids =
 		(TransactionId *) ShmemAlloc(TotalProcs * sizeof(*ProcGlobal->xids));
-	MemSet(ProcGlobal->xids, 0, TotalProcs * sizeof(*ProcGlobal->xids));
+	memset(ProcGlobal->xids, 0, TotalProcs * sizeof(*ProcGlobal->xids));
 	ProcGlobal->subxidStates = (XidCacheStatus *) ShmemAlloc(TotalProcs * sizeof(*ProcGlobal->subxidStates));
-	MemSet(ProcGlobal->subxidStates, 0, TotalProcs * sizeof(*ProcGlobal->subxidStates));
+	memset(ProcGlobal->subxidStates, 0, TotalProcs * sizeof(*ProcGlobal->subxidStates));
 	ProcGlobal->statusFlags = (uint8 *) ShmemAlloc(TotalProcs * sizeof(*ProcGlobal->statusFlags));
-	MemSet(ProcGlobal->statusFlags, 0, TotalProcs * sizeof(*ProcGlobal->statusFlags));
+	memset(ProcGlobal->statusFlags, 0, TotalProcs * sizeof(*ProcGlobal->statusFlags));
 
 	for (i = 0; i < TotalProcs; i++)
 	{
diff --git a/src/backend/storage/page/bufpage.c b/src/backend/storage/page/bufpage.c
index a3d367db51..b75cb7e943 100644
--- a/src/backend/storage/page/bufpage.c
+++ b/src/backend/storage/page/bufpage.c
@@ -49,14 +49,14 @@ PageInit(Page page, Size pageSize, Size specialSize)
 	Assert(pageSize > specialSize + SizeOfPageHeaderData);
 
 	/* Make sure all fields of page are zero, as well as unused space */
-	MemSet(p, 0, pageSize);
+	memset(p, 0, pageSize);
 
 	p->pd_flags = 0;
 	p->pd_lower = SizeOfPageHeaderData;
 	p->pd_upper = pageSize - specialSize;
 	p->pd_special = pageSize - specialSize;
 	PageSetPageSizeAndVersion(page, pageSize, PG_PAGE_LAYOUT_VERSION);
-	/* p->pd_prune_xid = InvalidTransactionId;		done by above MemSet */
+	/* p->pd_prune_xid = InvalidTransactionId;		done by above memset */
 }
 
 
diff --git a/src/backend/storage/smgr/md.c b/src/backend/storage/smgr/md.c
index 43edaf5d87..4aae2decbb 100644
--- a/src/backend/storage/smgr/md.c
+++ b/src/backend/storage/smgr/md.c
@@ -684,7 +684,7 @@ mdread(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 		 * update a block that was later truncated away.
 		 */
 		if (zero_damaged_pages || InRecovery)
-			MemSet(buffer, 0, BLCKSZ);
+			memset(buffer, 0, BLCKSZ);
 		else
 			ereport(ERROR,
 					(errcode(ERRCODE_DATA_CORRUPTED),
diff --git a/src/backend/tcop/fastpath.c b/src/backend/tcop/fastpath.c
index d429aa4663..c6ec536463 100644
--- a/src/backend/tcop/fastpath.c
+++ b/src/backend/tcop/fastpath.c
@@ -131,7 +131,7 @@ fetch_fp_info(Oid func_id, struct fp_info *fip)
 	 * time.  [No longer really an issue since we don't save the struct
 	 * fp_info across transactions anymore, but keep it anyway.]
 	 */
-	MemSet(fip, 0, sizeof(struct fp_info));
+	memset(fip, 0, sizeof(struct fp_info));
 	fip->funcid = InvalidOid;
 
 	func_htp = SearchSysCache1(PROCOID, ObjectIdGetDatum(func_id));
diff --git a/src/backend/utils/activity/backend_progress.c b/src/backend/utils/activity/backend_progress.c
index f29199725b..d12402a050 100644
--- a/src/backend/utils/activity/backend_progress.c
+++ b/src/backend/utils/activity/backend_progress.c
@@ -33,7 +33,7 @@ pgstat_progress_start_command(ProgressCommandType cmdtype, Oid relid)
 	PGSTAT_BEGIN_WRITE_ACTIVITY(beentry);
 	beentry->st_progress_command = cmdtype;
 	beentry->st_progress_command_target = relid;
-	MemSet(&beentry->st_progress_param, 0, sizeof(beentry->st_progress_param));
+	memset(&beentry->st_progress_param, 0, sizeof(beentry->st_progress_param));
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 }
 
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index c7ed1e6d7a..96f0a815c1 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -131,7 +131,7 @@ CreateSharedBackendStatus(void)
 		/*
 		 * We're the first - initialize.
 		 */
-		MemSet(BackendStatusArray, 0, size);
+		memset(BackendStatusArray, 0, size);
 	}
 
 	/* Create or attach to the shared appname buffer */
@@ -141,7 +141,7 @@ CreateSharedBackendStatus(void)
 
 	if (!found)
 	{
-		MemSet(BackendAppnameBuffer, 0, size);
+		memset(BackendAppnameBuffer, 0, size);
 
 		/* Initialize st_appname pointers. */
 		buffer = BackendAppnameBuffer;
@@ -159,7 +159,7 @@ CreateSharedBackendStatus(void)
 
 	if (!found)
 	{
-		MemSet(BackendClientHostnameBuffer, 0, size);
+		memset(BackendClientHostnameBuffer, 0, size);
 
 		/* Initialize st_clienthostname pointers. */
 		buffer = BackendClientHostnameBuffer;
@@ -180,7 +180,7 @@ CreateSharedBackendStatus(void)
 
 	if (!found)
 	{
-		MemSet(BackendActivityBuffer, 0, BackendActivityBufferSize);
+		memset(BackendActivityBuffer, 0, BackendActivityBufferSize);
 
 		/* Initialize st_activity pointers. */
 		buffer = BackendActivityBuffer;
@@ -201,7 +201,7 @@ CreateSharedBackendStatus(void)
 	{
 		PgBackendSSLStatus *ptr;
 
-		MemSet(BackendSslStatusBuffer, 0, size);
+		memset(BackendSslStatusBuffer, 0, size);
 
 		/* Initialize st_sslstatus pointers. */
 		ptr = BackendSslStatusBuffer;
@@ -223,7 +223,7 @@ CreateSharedBackendStatus(void)
 	{
 		PgBackendGSSStatus *ptr;
 
-		MemSet(BackendGssStatusBuffer, 0, size);
+		memset(BackendGssStatusBuffer, 0, size);
 
 		/* Initialize st_gssstatus pointers. */
 		ptr = BackendGssStatusBuffer;
@@ -355,7 +355,7 @@ pgstat_bestart(void)
 		memcpy(&lbeentry.st_clientaddr, &MyProcPort->raddr,
 			   sizeof(lbeentry.st_clientaddr));
 	else
-		MemSet(&lbeentry.st_clientaddr, 0, sizeof(lbeentry.st_clientaddr));
+		memset(&lbeentry.st_clientaddr, 0, sizeof(lbeentry.st_clientaddr));
 
 #ifdef USE_SSL
 	if (MyProcPort && MyProcPort->ssl_in_use)
diff --git a/src/backend/utils/activity/pgstat_bgwriter.c b/src/backend/utils/activity/pgstat_bgwriter.c
index fbb1edc527..ced6e10a2a 100644
--- a/src/backend/utils/activity/pgstat_bgwriter.c
+++ b/src/backend/utils/activity/pgstat_bgwriter.c
@@ -55,7 +55,7 @@ pgstat_report_bgwriter(void)
 	/*
 	 * Clear out the statistics buffer, so it can be re-used.
 	 */
-	MemSet(&PendingBgWriterStats, 0, sizeof(PendingBgWriterStats));
+	memset(&PendingBgWriterStats, 0, sizeof(PendingBgWriterStats));
 }
 
 /*
diff --git a/src/backend/utils/activity/pgstat_checkpointer.c b/src/backend/utils/activity/pgstat_checkpointer.c
index af8d513e7b..ba64aec5c5 100644
--- a/src/backend/utils/activity/pgstat_checkpointer.c
+++ b/src/backend/utils/activity/pgstat_checkpointer.c
@@ -61,7 +61,7 @@ pgstat_report_checkpointer(void)
 	/*
 	 * Clear out the statistics buffer, so it can be re-used.
 	 */
-	MemSet(&PendingCheckpointerStats, 0, sizeof(PendingCheckpointerStats));
+	memset(&PendingCheckpointerStats, 0, sizeof(PendingCheckpointerStats));
 }
 
 /*
diff --git a/src/backend/utils/activity/pgstat_slru.c b/src/backend/utils/activity/pgstat_slru.c
index d0b85b62a5..0c1eb70251 100644
--- a/src/backend/utils/activity/pgstat_slru.c
+++ b/src/backend/utils/activity/pgstat_slru.c
@@ -185,7 +185,7 @@ pgstat_slru_flush(bool nowait)
 	}
 
 	/* done, clear the pending entry */
-	MemSet(pending_SLRUStats, 0, sizeof(pending_SLRUStats));
+	memset(pending_SLRUStats, 0, sizeof(pending_SLRUStats));
 
 	LWLockRelease(&stats_shmem->lock);
 
diff --git a/src/backend/utils/activity/pgstat_wal.c b/src/backend/utils/activity/pgstat_wal.c
index 5a878bd115..d6f9866ba7 100644
--- a/src/backend/utils/activity/pgstat_wal.c
+++ b/src/backend/utils/activity/pgstat_wal.c
@@ -117,7 +117,7 @@ pgstat_flush_wal(bool nowait)
 	/*
 	 * Clear out the statistics buffer, so it can be re-used.
 	 */
-	MemSet(&PendingWalStats, 0, sizeof(PendingWalStats));
+	memset(&PendingWalStats, 0, sizeof(PendingWalStats));
 
 	return false;
 }
diff --git a/src/backend/utils/adt/acl.c b/src/backend/utils/adt/acl.c
index 772c04155c..2ee786dc6b 100644
--- a/src/backend/utils/adt/acl.c
+++ b/src/backend/utils/adt/acl.c
@@ -1819,7 +1819,7 @@ aclexplode(PG_FUNCTION_ARGS)
 			values[2] = CStringGetTextDatum(convert_aclright_to_string(priv_bit));
 			values[3] = BoolGetDatum((ACLITEM_GET_GOPTIONS(*aidata) & priv_bit) != 0);
 
-			MemSet(nulls, 0, sizeof(nulls));
+			memset(nulls, 0, sizeof(nulls));
 
 			tuple = heap_form_tuple(funcctx->tuple_desc, values, nulls);
 			result = HeapTupleGetDatum(tuple);
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index 2570e5e630..14b7532b67 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -746,7 +746,7 @@ ReadArrayStr(char *arrayStr,
 				prod[MAXDIM];
 
 	mda_get_prod(ndim, dim, prod);
-	MemSet(indx, 0, sizeof(indx));
+	memset(indx, 0, sizeof(indx));
 
 	/* Initialize is-null markers to true */
 	memset(nulls, true, nitems * sizeof(bool));
@@ -2460,7 +2460,7 @@ array_set_element(Datum arraydatum,
 		bits8	   *newnullbitmap = ARR_NULLBITMAP(newarray);
 
 		/* Zero the bitmap to take care of marking inserted positions null */
-		MemSet(newnullbitmap, 0, (newnitems + 7) / 8);
+		memset(newnullbitmap, 0, (newnitems + 7) / 8);
 		/* Fix the inserted value */
 		if (addedafter)
 			array_set_isnull(newnullbitmap, newnitems - 1, isNull);
@@ -3077,7 +3077,7 @@ array_set_slice(Datum arraydatum,
 			bits8	   *oldnullbitmap = ARR_NULLBITMAP(array);
 
 			/* Zero the bitmap to handle marking inserted positions null */
-			MemSet(newnullbitmap, 0, (nitems + 7) / 8);
+			memset(newnullbitmap, 0, (nitems + 7) / 8);
 			array_bitmap_copy(newnullbitmap, addedbefore,
 							  oldnullbitmap, 0,
 							  itemsbefore);
diff --git a/src/backend/utils/adt/datetime.c b/src/backend/utils/adt/datetime.c
index 4c12c4d663..99ef3df049 100644
--- a/src/backend/utils/adt/datetime.c
+++ b/src/backend/utils/adt/datetime.c
@@ -5011,7 +5011,7 @@ pg_timezone_abbrevs(PG_FUNCTION_ARGS)
 			break;
 	}
 
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(nulls, 0, sizeof(nulls));
 
 	/*
 	 * Convert name to text, using upcasing conversion that is the inverse of
@@ -5024,7 +5024,7 @@ pg_timezone_abbrevs(PG_FUNCTION_ARGS)
 	values[0] = CStringGetTextDatum(buffer);
 
 	/* Convert offset (in seconds) to an interval; can't overflow */
-	MemSet(&itm_in, 0, sizeof(struct pg_itm_in));
+	memset(&itm_in, 0, sizeof(struct pg_itm_in));
 	itm_in.tm_usec = (int64) gmtoffset * USECS_PER_SEC;
 	resInterval = (Interval *) palloc(sizeof(Interval));
 	(void) itmin2interval(&itm_in, resInterval);
@@ -5088,13 +5088,13 @@ pg_timezone_names(PG_FUNCTION_ARGS)
 		if (tzn && strlen(tzn) > 31)
 			continue;
 
-		MemSet(nulls, 0, sizeof(nulls));
+		memset(nulls, 0, sizeof(nulls));
 
 		values[0] = CStringGetTextDatum(pg_get_timezone_name(tz));
 		values[1] = CStringGetTextDatum(tzn ? tzn : "");
 
 		/* Convert tzoff to an interval; can't overflow */
-		MemSet(&itm_in, 0, sizeof(struct pg_itm_in));
+		memset(&itm_in, 0, sizeof(struct pg_itm_in));
 		itm_in.tm_usec = (int64) -tzoff * USECS_PER_SEC;
 		resInterval = (Interval *) palloc(sizeof(Interval));
 		(void) itmin2interval(&itm_in, resInterval);
diff --git a/src/backend/utils/adt/formatting.c b/src/backend/utils/adt/formatting.c
index e909c1a200..31105b9519 100644
--- a/src/backend/utils/adt/formatting.c
+++ b/src/backend/utils/adt/formatting.c
@@ -5626,7 +5626,7 @@ NUM_processor(FormatNode *node, NUMDesc *Num, char *inout,
 	const char *pattern;
 	int			pattern_len;
 
-	MemSet(Np, 0, sizeof(NUMProc));
+	memset(Np, 0, sizeof(NUMProc));
 
 	Np->Num = Num;
 	Np->is_to_char = is_to_char;
diff --git a/src/backend/utils/adt/jsonfuncs.c b/src/backend/utils/adt/jsonfuncs.c
index d427bdfbe0..52ff421e36 100644
--- a/src/backend/utils/adt/jsonfuncs.c
+++ b/src/backend/utils/adt/jsonfuncs.c
@@ -3190,7 +3190,7 @@ allocate_record_info(MemoryContext mcxt, int ncolumns)
 	data->record_type = InvalidOid;
 	data->record_typmod = 0;
 	data->ncolumns = ncolumns;
-	MemSet(data->columns, 0, sizeof(ColumnIOData) * ncolumns);
+	memset(data->columns, 0, sizeof(ColumnIOData) * ncolumns);
 
 	return data;
 }
@@ -3254,7 +3254,7 @@ populate_record(TupleDesc tupdesc,
 	if (record->record_type != tupdesc->tdtypeid ||
 		record->record_typmod != tupdesc->tdtypmod)
 	{
-		MemSet(record, 0, offsetof(RecordIOData, columns) +
+		memset(record, 0, offsetof(RecordIOData, columns) +
 			   ncolumns * sizeof(ColumnIOData));
 		record->record_type = tupdesc->tdtypeid;
 		record->record_typmod = tupdesc->tdtypmod;
diff --git a/src/backend/utils/adt/lockfuncs.c b/src/backend/utils/adt/lockfuncs.c
index 023a004ac8..6c5f9ebaee 100644
--- a/src/backend/utils/adt/lockfuncs.c
+++ b/src/backend/utils/adt/lockfuncs.c
@@ -230,8 +230,8 @@ pg_lock_status(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
+		memset(values, 0, sizeof(values));
+		memset(nulls, false, sizeof(nulls));
 
 		if (instance->locktag.locktag_type <= LOCKTAG_LAST_TYPE)
 			locktypename = LockTagTypeNames[instance->locktag.locktag_type];
@@ -369,8 +369,8 @@ pg_lock_status(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
+		memset(values, 0, sizeof(values));
+		memset(nulls, false, sizeof(nulls));
 
 		/* lock type */
 		lockType = GET_PREDICATELOCKTARGETTAG_TYPE(*predTag);
diff --git a/src/backend/utils/adt/partitionfuncs.c b/src/backend/utils/adt/partitionfuncs.c
index 0243bc061f..468bd7b34f 100644
--- a/src/backend/utils/adt/partitionfuncs.c
+++ b/src/backend/utils/adt/partitionfuncs.c
@@ -126,8 +126,8 @@ pg_partition_tree(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(nulls, 0, sizeof(nulls));
-		MemSet(values, 0, sizeof(values));
+		memset(nulls, 0, sizeof(nulls));
+		memset(values, 0, sizeof(values));
 
 		/* relid */
 		values[0] = ObjectIdGetDatum(relid);
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 893690dad5..94db404d02 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -492,8 +492,8 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 		bool		nulls[PG_STAT_GET_PROGRESS_COLS];
 		int			i;
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
+		memset(values, 0, sizeof(values));
+		memset(nulls, 0, sizeof(nulls));
 
 		local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
 
@@ -559,8 +559,8 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 		const char *wait_event_type = NULL;
 		const char *wait_event = NULL;
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
+		memset(values, 0, sizeof(values));
+		memset(nulls, 0, sizeof(nulls));
 
 		/* Get the next one in the list */
 		local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
@@ -1753,8 +1753,8 @@ pg_stat_get_wal(PG_FUNCTION_ARGS)
 	PgStat_WalStats *wal_stats;
 
 	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(values, 0, sizeof(values));
+	memset(nulls, 0, sizeof(nulls));
 
 	/* Initialise attributes information in the tuple descriptor */
 	tupdesc = CreateTemplateTupleDesc(PG_STAT_GET_WAL_COLS);
@@ -1837,8 +1837,8 @@ pg_stat_get_slru(PG_FUNCTION_ARGS)
 			break;
 
 		stat = stats[i];
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
+		memset(values, 0, sizeof(values));
+		memset(nulls, 0, sizeof(nulls));
 
 		values[0] = PointerGetDatum(cstring_to_text(name));
 		values[1] = Int64GetDatum(stat.blocks_zeroed);
@@ -2206,8 +2206,8 @@ pg_stat_get_archiver(PG_FUNCTION_ARGS)
 	PgStat_ArchiverStats *archiver_stats;
 
 	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(values, 0, sizeof(values));
+	memset(nulls, 0, sizeof(nulls));
 
 	/* Initialise attributes information in the tuple descriptor */
 	tupdesc = CreateTemplateTupleDesc(7);
@@ -2280,8 +2280,8 @@ pg_stat_get_replication_slot(PG_FUNCTION_ARGS)
 	PgStat_StatReplSlotEntry allzero;
 
 	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(values, 0, sizeof(values));
+	memset(nulls, 0, sizeof(nulls));
 
 	/* Initialise attributes information in the tuple descriptor */
 	tupdesc = CreateTemplateTupleDesc(PG_STAT_GET_REPLICATION_SLOT_COLS);
@@ -2369,8 +2369,8 @@ pg_stat_get_subscription_stats(PG_FUNCTION_ARGS)
 	BlessTupleDesc(tupdesc);
 
 	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(values, 0, sizeof(values));
+	memset(nulls, 0, sizeof(nulls));
 
 	if (!subentry)
 	{
diff --git a/src/backend/utils/adt/rowtypes.c b/src/backend/utils/adt/rowtypes.c
index db843a0fbf..7c9eefc741 100644
--- a/src/backend/utils/adt/rowtypes.c
+++ b/src/backend/utils/adt/rowtypes.c
@@ -132,7 +132,7 @@ record_in(PG_FUNCTION_ARGS)
 	if (my_extra->record_type != tupType ||
 		my_extra->record_typmod != tupTypmod)
 	{
-		MemSet(my_extra, 0,
+		memset(my_extra, 0,
 			   offsetof(RecordIOData, columns) +
 			   ncolumns * sizeof(ColumnIOData));
 		my_extra->record_type = tupType;
@@ -349,7 +349,7 @@ record_out(PG_FUNCTION_ARGS)
 	if (my_extra->record_type != tupType ||
 		my_extra->record_typmod != tupTypmod)
 	{
-		MemSet(my_extra, 0,
+		memset(my_extra, 0,
 			   offsetof(RecordIOData, columns) +
 			   ncolumns * sizeof(ColumnIOData));
 		my_extra->record_type = tupType;
@@ -505,7 +505,7 @@ record_recv(PG_FUNCTION_ARGS)
 	if (my_extra->record_type != tupType ||
 		my_extra->record_typmod != tupTypmod)
 	{
-		MemSet(my_extra, 0,
+		memset(my_extra, 0,
 			   offsetof(RecordIOData, columns) +
 			   ncolumns * sizeof(ColumnIOData));
 		my_extra->record_type = tupType;
@@ -716,7 +716,7 @@ record_send(PG_FUNCTION_ARGS)
 	if (my_extra->record_type != tupType ||
 		my_extra->record_typmod != tupTypmod)
 	{
-		MemSet(my_extra, 0,
+		memset(my_extra, 0,
 			   offsetof(RecordIOData, columns) +
 			   ncolumns * sizeof(ColumnIOData));
 		my_extra->record_type = tupType;
@@ -876,7 +876,7 @@ record_cmp(FunctionCallInfo fcinfo)
 		my_extra->record2_type != tupType2 ||
 		my_extra->record2_typmod != tupTypmod2)
 	{
-		MemSet(my_extra->columns, 0, ncols * sizeof(ColumnCompareData));
+		memset(my_extra->columns, 0, ncols * sizeof(ColumnCompareData));
 		my_extra->record1_type = tupType1;
 		my_extra->record1_typmod = tupTypmod1;
 		my_extra->record2_type = tupType2;
@@ -1120,7 +1120,7 @@ record_eq(PG_FUNCTION_ARGS)
 		my_extra->record2_type != tupType2 ||
 		my_extra->record2_typmod != tupTypmod2)
 	{
-		MemSet(my_extra->columns, 0, ncols * sizeof(ColumnCompareData));
+		memset(my_extra->columns, 0, ncols * sizeof(ColumnCompareData));
 		my_extra->record1_type = tupType1;
 		my_extra->record1_typmod = tupTypmod1;
 		my_extra->record2_type = tupType2;
@@ -1382,7 +1382,7 @@ record_image_cmp(FunctionCallInfo fcinfo)
 		my_extra->record2_type != tupType2 ||
 		my_extra->record2_typmod != tupTypmod2)
 	{
-		MemSet(my_extra->columns, 0, ncols * sizeof(ColumnCompareData));
+		memset(my_extra->columns, 0, ncols * sizeof(ColumnCompareData));
 		my_extra->record1_type = tupType1;
 		my_extra->record1_typmod = tupTypmod1;
 		my_extra->record2_type = tupType2;
@@ -1628,7 +1628,7 @@ record_image_eq(PG_FUNCTION_ARGS)
 		my_extra->record2_type != tupType2 ||
 		my_extra->record2_typmod != tupTypmod2)
 	{
-		MemSet(my_extra->columns, 0, ncols * sizeof(ColumnCompareData));
+		memset(my_extra->columns, 0, ncols * sizeof(ColumnCompareData));
 		my_extra->record1_type = tupType1;
 		my_extra->record1_typmod = tupTypmod1;
 		my_extra->record2_type = tupType2;
@@ -1822,7 +1822,7 @@ hash_record(PG_FUNCTION_ARGS)
 	if (my_extra->record1_type != tupType ||
 		my_extra->record1_typmod != tupTypmod)
 	{
-		MemSet(my_extra->columns, 0, ncolumns * sizeof(ColumnCompareData));
+		memset(my_extra->columns, 0, ncolumns * sizeof(ColumnCompareData));
 		my_extra->record1_type = tupType;
 		my_extra->record1_typmod = tupTypmod;
 	}
@@ -1943,7 +1943,7 @@ hash_record_extended(PG_FUNCTION_ARGS)
 	if (my_extra->record1_type != tupType ||
 		my_extra->record1_typmod != tupTypmod)
 	{
-		MemSet(my_extra->columns, 0, ncolumns * sizeof(ColumnCompareData));
+		memset(my_extra->columns, 0, ncolumns * sizeof(ColumnCompareData));
 		my_extra->record1_type = tupType;
 		my_extra->record1_typmod = tupTypmod;
 	}
diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c
index fa1f589fad..243feb2340 100644
--- a/src/backend/utils/adt/selfuncs.c
+++ b/src/backend/utils/adt/selfuncs.c
@@ -4992,7 +4992,7 @@ examine_variable(PlannerInfo *root, Node *node, int varRelid,
 	RelOptInfo *onerel;
 
 	/* Make sure we don't return dangling pointers in vardata */
-	MemSet(vardata, 0, sizeof(VariableStatData));
+	memset(vardata, 0, sizeof(VariableStatData));
 
 	/* Save the exposed type of the expression */
 	vardata->vartype = exprType(node);
@@ -6797,7 +6797,7 @@ btcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	/*
 	 * Now do generic index cost estimation.
 	 */
-	MemSet(&costs, 0, sizeof(costs));
+	memset(&costs, 0, sizeof(costs));
 	costs.numIndexTuples = numIndexTuples;
 
 	genericcostestimate(root, path, loop_count, &costs);
@@ -6842,7 +6842,7 @@ btcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	 * ordering, but don't negate it entirely.  Before 8.0 we divided the
 	 * correlation by the number of columns, but that seems too strong.)
 	 */
-	MemSet(&vardata, 0, sizeof(vardata));
+	memset(&vardata, 0, sizeof(vardata));
 
 	if (index->indexkeys[0] != 0)
 	{
@@ -6949,7 +6949,7 @@ hashcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 {
 	GenericCosts costs;
 
-	MemSet(&costs, 0, sizeof(costs));
+	memset(&costs, 0, sizeof(costs));
 
 	genericcostestimate(root, path, loop_count, &costs);
 
@@ -6995,7 +6995,7 @@ gistcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	GenericCosts costs;
 	Cost		descentCost;
 
-	MemSet(&costs, 0, sizeof(costs));
+	memset(&costs, 0, sizeof(costs));
 
 	genericcostestimate(root, path, loop_count, &costs);
 
@@ -7052,7 +7052,7 @@ spgcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	GenericCosts costs;
 	Cost		descentCost;
 
-	MemSet(&costs, 0, sizeof(costs));
+	memset(&costs, 0, sizeof(costs));
 
 	genericcostestimate(root, path, loop_count, &costs);
 
diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index f70f829d83..0821a4e639 100644
--- a/src/backend/utils/adt/timestamp.c
+++ b/src/backend/utils/adt/timestamp.c
@@ -5800,7 +5800,7 @@ generate_series_timestamp(PG_FUNCTION_ARGS)
 		fctx->step = *step;
 
 		/* Determine sign of the interval */
-		MemSet(&interval_zero, 0, sizeof(Interval));
+		memset(&interval_zero, 0, sizeof(Interval));
 		fctx->step_sign = interval_cmp_internal(&fctx->step, &interval_zero);
 
 		if (fctx->step_sign == 0)
@@ -5880,7 +5880,7 @@ generate_series_timestamptz(PG_FUNCTION_ARGS)
 		fctx->step = *step;
 
 		/* Determine sign of the interval */
-		MemSet(&interval_zero, 0, sizeof(Interval));
+		memset(&interval_zero, 0, sizeof(Interval));
 		fctx->step_sign = interval_cmp_internal(&fctx->step, &interval_zero);
 
 		if (fctx->step_sign == 0)
diff --git a/src/backend/utils/adt/tsgistidx.c b/src/backend/utils/adt/tsgistidx.c
index b8fd96dd7b..9b73030fa8 100644
--- a/src/backend/utils/adt/tsgistidx.c
+++ b/src/backend/utils/adt/tsgistidx.c
@@ -141,7 +141,7 @@ makesign(BITVECP sign, SignTSVector *a, int siglen)
 				len = ARRNELEM(a);
 	int32	   *ptr = GETARR(a);
 
-	MemSet((void *) sign, 0, siglen);
+	memset((void *) sign, 0, siglen);
 	for (k = 0; k < len; k++)
 		HASH(sign, ptr[k], siglen);
 }
@@ -753,7 +753,7 @@ gtsvector_picksplit(PG_FUNCTION_ARGS)
 			if (ISALLTRUE(datum_l) || cache[j].allistrue)
 			{
 				if (!ISALLTRUE(datum_l))
-					MemSet((void *) GETSIGN(datum_l), 0xff, siglen);
+					memset((void *) GETSIGN(datum_l), 0xff, siglen);
 			}
 			else
 			{
@@ -769,7 +769,7 @@ gtsvector_picksplit(PG_FUNCTION_ARGS)
 			if (ISALLTRUE(datum_r) || cache[j].allistrue)
 			{
 				if (!ISALLTRUE(datum_r))
-					MemSet((void *) GETSIGN(datum_r), 0xff, siglen);
+					memset((void *) GETSIGN(datum_r), 0xff, siglen);
 			}
 			else
 			{
diff --git a/src/backend/utils/adt/tsrank.c b/src/backend/utils/adt/tsrank.c
index 3858fc5928..da8a777fad 100644
--- a/src/backend/utils/adt/tsrank.c
+++ b/src/backend/utils/adt/tsrank.c
@@ -883,7 +883,7 @@ calc_rank_cd(const float4 *arrdata, TSVector txt, TSQuery query, int method)
 		return 0.0;
 	}
 
-	MemSet(&ext, 0, sizeof(CoverExt));
+	memset(&ext, 0, sizeof(CoverExt));
 	while (Cover(doc, doclen, &qr, &ext))
 	{
 		double		Cpos = 0.0;
diff --git a/src/backend/utils/adt/varbit.c b/src/backend/utils/adt/varbit.c
index 73e41e0808..b3541908e2 100644
--- a/src/backend/utils/adt/varbit.c
+++ b/src/backend/utils/adt/varbit.c
@@ -1419,7 +1419,7 @@ bitshiftleft(PG_FUNCTION_ARGS)
 	/* If we shifted all the bits out, return an all-zero string */
 	if (shft >= VARBITLEN(arg))
 	{
-		MemSet(r, 0, VARBITBYTES(arg));
+		memset(r, 0, VARBITBYTES(arg));
 		PG_RETURN_VARBIT_P(result);
 	}
 
@@ -1432,7 +1432,7 @@ bitshiftleft(PG_FUNCTION_ARGS)
 		/* Special case: we can do a memcpy */
 		len = VARBITBYTES(arg) - byte_shift;
 		memcpy(r, p, len);
-		MemSet(r + len, 0, byte_shift);
+		memset(r + len, 0, byte_shift);
 	}
 	else
 	{
@@ -1486,7 +1486,7 @@ bitshiftright(PG_FUNCTION_ARGS)
 	/* If we shifted all the bits out, return an all-zero string */
 	if (shft >= VARBITLEN(arg))
 	{
-		MemSet(r, 0, VARBITBYTES(arg));
+		memset(r, 0, VARBITBYTES(arg));
 		PG_RETURN_VARBIT_P(result);
 	}
 
@@ -1495,7 +1495,7 @@ bitshiftright(PG_FUNCTION_ARGS)
 	p = VARBITS(arg);
 
 	/* Set the first part of the result to 0 */
-	MemSet(r, 0, byte_shift);
+	memset(r, 0, byte_shift);
 	r += byte_shift;
 
 	if (ishift == 0)
diff --git a/src/backend/utils/cache/relfilenodemap.c b/src/backend/utils/cache/relfilenodemap.c
index 70c323c720..5dbf3c0b7d 100644
--- a/src/backend/utils/cache/relfilenodemap.c
+++ b/src/backend/utils/cache/relfilenodemap.c
@@ -95,7 +95,7 @@ InitializeRelfilenodeMap(void)
 		CreateCacheMemoryContext();
 
 	/* build skey */
-	MemSet(&relfilenode_skey, 0, sizeof(relfilenode_skey));
+	memset(&relfilenode_skey, 0, sizeof(relfilenode_skey));
 
 	for (i = 0; i < 2; i++)
 	{
@@ -153,7 +153,7 @@ RelidByRelfilenode(Oid reltablespace, Oid relfilenode)
 	if (reltablespace == MyDatabaseTableSpace)
 		reltablespace = 0;
 
-	MemSet(&key, 0, sizeof(key));
+	memset(&key, 0, sizeof(key));
 	key.reltablespace = reltablespace;
 	key.relfilenode = relfilenode;
 
diff --git a/src/backend/utils/cache/ts_cache.c b/src/backend/utils/cache/ts_cache.c
index 24808dfbb1..fbb4df7bf2 100644
--- a/src/backend/utils/cache/ts_cache.c
+++ b/src/backend/utils/cache/ts_cache.c
@@ -176,7 +176,7 @@ lookup_ts_parser_cache(Oid prsId)
 			Assert(!found);		/* it wasn't there a moment ago */
 		}
 
-		MemSet(entry, 0, sizeof(TSParserCacheEntry));
+		memset(entry, 0, sizeof(TSParserCacheEntry));
 		entry->prsId = prsId;
 		entry->startOid = prs->prsstart;
 		entry->tokenOid = prs->prstoken;
@@ -306,7 +306,7 @@ lookup_ts_dictionary_cache(Oid dictId)
 			MemoryContextCopyAndSetIdentifier(saveCtx, NameStr(dict->dictname));
 		}
 
-		MemSet(entry, 0, sizeof(TSDictionaryCacheEntry));
+		memset(entry, 0, sizeof(TSDictionaryCacheEntry));
 		entry->dictId = dictId;
 		entry->dictCtx = saveCtx;
 
@@ -455,7 +455,7 @@ lookup_ts_config_cache(Oid cfgId)
 			}
 		}
 
-		MemSet(entry, 0, sizeof(TSConfigCacheEntry));
+		memset(entry, 0, sizeof(TSConfigCacheEntry));
 		entry->cfgId = cfgId;
 		entry->prsId = cfg->cfgparser;
 
@@ -468,7 +468,7 @@ lookup_ts_config_cache(Oid cfgId)
 		 * see the entries in maptokentype order, and in mapseqno order for
 		 * each token type, even though we didn't explicitly ask for that.
 		 */
-		MemSet(maplists, 0, sizeof(maplists));
+		memset(maplists, 0, sizeof(maplists));
 		maxtokentype = 0;
 		ndicts = 0;
 
diff --git a/src/backend/utils/cache/typcache.c b/src/backend/utils/cache/typcache.c
index 808f9ebd0d..0fe0255b02 100644
--- a/src/backend/utils/cache/typcache.c
+++ b/src/backend/utils/cache/typcache.c
@@ -396,7 +396,7 @@ lookup_type_cache(Oid type_id, int flags)
 												  HASH_ENTER, &found);
 		Assert(!found);			/* it wasn't there a moment ago */
 
-		MemSet(typentry, 0, sizeof(TypeCacheEntry));
+		memset(typentry, 0, sizeof(TypeCacheEntry));
 
 		/* These fields can never change, by definition */
 		typentry->type_id = type_id;
diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index 55ee5423af..e1f4aa302b 100644
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -443,7 +443,7 @@ errstart(int elevel, const char *domain)
 
 	/* Initialize data for this error frame */
 	edata = &errordata[errordata_stack_depth];
-	MemSet(edata, 0, sizeof(ErrorData));
+	memset(edata, 0, sizeof(ErrorData));
 	edata->elevel = elevel;
 	edata->output_to_server = output_to_server;
 	edata->output_to_client = output_to_client;
@@ -1476,7 +1476,7 @@ format_elog_string(const char *fmt,...)
 
 	/* Initialize a mostly-dummy error frame */
 	edata = &errdata;
-	MemSet(edata, 0, sizeof(ErrorData));
+	memset(edata, 0, sizeof(ErrorData));
 	/* the default text domain is the backend's */
 	edata->domain = save_format_domain ? save_format_domain : PG_TEXTDOMAIN("postgres");
 	/* set the errno to be used to interpret %m */
@@ -1872,7 +1872,7 @@ GetErrorContextStack(void)
 	 * Things look good so far, so initialize our error frame
 	 */
 	edata = &errordata[errordata_stack_depth];
-	MemSet(edata, 0, sizeof(ErrorData));
+	memset(edata, 0, sizeof(ErrorData));
 
 	/*
 	 * Set up assoc_context to be the caller's context, so any allocations
diff --git a/src/backend/utils/fmgr/dfmgr.c b/src/backend/utils/fmgr/dfmgr.c
index 7f9ea97280..ee69dc8bf2 100644
--- a/src/backend/utils/fmgr/dfmgr.c
+++ b/src/backend/utils/fmgr/dfmgr.c
@@ -228,7 +228,7 @@ internal_load_library(const char *libname)
 					(errcode(ERRCODE_OUT_OF_MEMORY),
 					 errmsg("out of memory")));
 
-		MemSet(file_scanner, 0, offsetof(DynamicFileList, filename));
+		memset(file_scanner, 0, offsetof(DynamicFileList, filename));
 		strcpy(file_scanner->filename, libname);
 		file_scanner->device = stat_buf.st_dev;
 #ifndef WIN32
diff --git a/src/backend/utils/hash/dynahash.c b/src/backend/utils/hash/dynahash.c
index 3babde8d70..27c5f3e80f 100644
--- a/src/backend/utils/hash/dynahash.c
+++ b/src/backend/utils/hash/dynahash.c
@@ -388,7 +388,7 @@ hash_create(const char *tabname, long nelem, const HASHCTL *info, int flags)
 
 	/* Initialize the hash header, plus a copy of the table name */
 	hashp = (HTAB *) DynaHashAlloc(sizeof(HTAB) + strlen(tabname) + 1);
-	MemSet(hashp, 0, sizeof(HTAB));
+	memset(hashp, 0, sizeof(HTAB));
 
 	hashp->tabname = (char *) (hashp + 1);
 	strcpy(hashp->tabname, tabname);
@@ -627,7 +627,7 @@ hdefault(HTAB *hashp)
 {
 	HASHHDR    *hctl = hashp->hctl;
 
-	MemSet(hctl, 0, sizeof(HASHHDR));
+	memset(hctl, 0, sizeof(HASHHDR));
 
 	hctl->dsize = DEF_DIRSIZE;
 	hctl->nsegs = 0;
@@ -1666,7 +1666,7 @@ dir_realloc(HTAB *hashp)
 	if (p != NULL)
 	{
 		memcpy(p, old_p, old_dirsize);
-		MemSet(((char *) p) + old_dirsize, 0, new_dirsize - old_dirsize);
+		memset(((char *) p) + old_dirsize, 0, new_dirsize - old_dirsize);
 		hashp->dir = p;
 		hashp->hctl->dsize = new_dsize;
 
@@ -1692,7 +1692,7 @@ seg_alloc(HTAB *hashp)
 	if (!segp)
 		return NULL;
 
-	MemSet(segp, 0, sizeof(HASHBUCKET) * hashp->ssize);
+	memset(segp, 0, sizeof(HASHBUCKET) * hashp->ssize);
 
 	return segp;
 }
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 8e9b71375c..2169604b02 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -11936,7 +11936,7 @@ check_wal_consistency_checking(char **newval, void **extra, GucSource source)
 	bool		newwalconsistency[RM_MAX_ID + 1];
 
 	/* Initialize the array */
-	MemSet(newwalconsistency, 0, (RM_MAX_ID + 1) * sizeof(bool));
+	memset(newwalconsistency, 0, (RM_MAX_ID + 1) * sizeof(bool));
 
 	/* Need a modifiable copy of string */
 	rawstring = pstrdup(*newval);
diff --git a/src/backend/utils/misc/ps_status.c b/src/backend/utils/misc/ps_status.c
index ec314c03f5..ca05b180c9 100644
--- a/src/backend/utils/misc/ps_status.c
+++ b/src/backend/utils/misc/ps_status.c
@@ -393,7 +393,7 @@ set_ps_display(const char *activity)
 #ifdef PS_USE_CLOBBER_ARGV
 	/* pad unused memory; need only clobber remainder of old status string */
 	if (last_status_len > ps_buffer_cur_len)
-		MemSet(ps_buffer + ps_buffer_cur_len, PS_PADDING,
+		memset(ps_buffer + ps_buffer_cur_len, PS_PADDING,
 			   last_status_len - ps_buffer_cur_len);
 	last_status_len = ps_buffer_cur_len;
 #endif							/* PS_USE_CLOBBER_ARGV */
diff --git a/src/backend/utils/misc/timeout.c b/src/backend/utils/misc/timeout.c
index 6f5e08bc30..16ff6250b1 100644
--- a/src/backend/utils/misc/timeout.c
+++ b/src/backend/utils/misc/timeout.c
@@ -216,7 +216,7 @@ schedule_alarm(TimestampTz now)
 		long		secs;
 		int			usecs;
 
-		MemSet(&timeval, 0, sizeof(struct itimerval));
+		memset(&timeval, 0, sizeof(struct itimerval));
 
 		/*
 		 * If we think there's a signal pending, but current time is more than
diff --git a/src/backend/utils/mmgr/portalmem.c b/src/backend/utils/mmgr/portalmem.c
index d549f66d4a..25ced094b9 100644
--- a/src/backend/utils/mmgr/portalmem.c
+++ b/src/backend/utils/mmgr/portalmem.c
@@ -1152,7 +1152,7 @@ pg_cursor(PG_FUNCTION_ARGS)
 		if (!portal->visible)
 			continue;
 
-		MemSet(nulls, 0, sizeof(nulls));
+		memset(nulls, 0, sizeof(nulls));
 
 		values[0] = CStringGetTextDatum(portal->name);
 		values[1] = CStringGetTextDatum(portal->sourceText);
diff --git a/src/backend/utils/sort/logtape.c b/src/backend/utils/sort/logtape.c
index c384f98e13..4a6dbb91ca 100644
--- a/src/backend/utils/sort/logtape.c
+++ b/src/backend/utils/sort/logtape.c
@@ -254,7 +254,7 @@ ltsWriteBlock(LogicalTapeSet *lts, long blocknum, void *buffer)
 	{
 		PGAlignedBlock zerobuf;
 
-		MemSet(zerobuf.data, 0, sizeof(zerobuf));
+		memset(zerobuf.data, 0, sizeof(zerobuf));
 
 		ltsWriteBlock(lts, lts->nBlocksWritten, zerobuf.data);
 	}
diff --git a/src/bin/pg_basebackup/pg_basebackup.c b/src/bin/pg_basebackup/pg_basebackup.c
index 4adb170d46..3f112e8082 100644
--- a/src/bin/pg_basebackup/pg_basebackup.c
+++ b/src/bin/pg_basebackup/pg_basebackup.c
@@ -457,7 +457,7 @@ reached_end_position(XLogRecPtr segendpos, uint32 timeline,
 		FD_ZERO(&fds);
 		FD_SET(bgpipe[0], &fds);
 
-		MemSet(&tv, 0, sizeof(tv));
+		memset(&tv, 0, sizeof(tv));
 
 		r = select(bgpipe[0] + 1, &fds, NULL, NULL, &tv);
 		if (r == 1)
@@ -466,7 +466,7 @@ reached_end_position(XLogRecPtr segendpos, uint32 timeline,
 			uint32		hi,
 						lo;
 
-			MemSet(xlogend, 0, sizeof(xlogend));
+			memset(xlogend, 0, sizeof(xlogend));
 			r = read(bgpipe[0], xlogend, sizeof(xlogend) - 1);
 			if (r < 0)
 				pg_fatal("could not read from ready pipe: %m");
@@ -532,7 +532,7 @@ LogStreamerMain(logstreamer_param *param)
 
 	in_log_streamer = true;
 
-	MemSet(&stream, 0, sizeof(stream));
+	memset(&stream, 0, sizeof(stream));
 	stream.startpos = param->startptr;
 	stream.timeline = param->timeline;
 	stream.sysidentifier = param->sysidentifier;
@@ -1961,7 +1961,7 @@ BaseBackup(char *compression_algorithm, char *compression_detail,
 	else
 		starttli = latesttli;
 	PQclear(res);
-	MemSet(xlogend, 0, sizeof(xlogend));
+	memset(xlogend, 0, sizeof(xlogend));
 
 	if (verbose && includewal != NO_WAL)
 		pg_log_info("write-ahead log start point: %s on timeline %u",
diff --git a/src/bin/pg_basebackup/pg_receivewal.c b/src/bin/pg_basebackup/pg_receivewal.c
index ea3902c971..c621588ceb 100644
--- a/src/bin/pg_basebackup/pg_receivewal.c
+++ b/src/bin/pg_basebackup/pg_receivewal.c
@@ -567,7 +567,7 @@ StreamLog(void)
 	StreamCtl	stream;
 	char	   *sysidentifier;
 
-	MemSet(&stream, 0, sizeof(stream));
+	memset(&stream, 0, sizeof(stream));
 
 	/*
 	 * Connect in replication mode to the server
diff --git a/src/bin/pg_basebackup/walmethods.c b/src/bin/pg_basebackup/walmethods.c
index cc292718da..bf838ef80e 100644
--- a/src/bin/pg_basebackup/walmethods.c
+++ b/src/bin/pg_basebackup/walmethods.c
@@ -1114,7 +1114,7 @@ tar_close(Walfile f, WalCloseMethod method)
 	{
 		char		zerobuf[TAR_BLOCK_SIZE];
 
-		MemSet(zerobuf, 0, padding);
+		memset(zerobuf, 0, padding);
 		if (tar_write(f, zerobuf, padding) != padding)
 			return -1;
 	}
@@ -1234,7 +1234,7 @@ tar_finish(void)
 	}
 
 	/* A tarfile always ends with two empty blocks */
-	MemSet(zerobuf, 0, sizeof(zerobuf));
+	memset(zerobuf, 0, sizeof(zerobuf));
 	if (tar_data->compression_algorithm == PG_COMPRESSION_NONE)
 	{
 		errno = 0;
diff --git a/src/common/fe_memutils.c b/src/common/fe_memutils.c
index 21fcce5430..9e433db245 100644
--- a/src/common/fe_memutils.c
+++ b/src/common/fe_memutils.c
@@ -39,7 +39,7 @@ pg_malloc_internal(size_t size, int flags)
 	}
 
 	if ((flags & MCXT_ALLOC_ZERO) != 0)
-		MemSet(tmp, 0, size);
+		memset(tmp, 0, size);
 	return tmp;
 }
 
diff --git a/src/common/ip.c b/src/common/ip.c
index cd73d49679..a574b58de2 100644
--- a/src/common/ip.c
+++ b/src/common/ip.c
@@ -171,7 +171,7 @@ getaddrinfo_unix(const char *path, const struct addrinfo *hintsp,
 
 	*result = NULL;
 
-	MemSet(&hints, 0, sizeof(hints));
+	memset(&hints, 0, sizeof(hints));
 
 	if (strlen(path) >= sizeof(unp->sun_path))
 		return EAI_FAIL;
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 6e936bbff3..5cdfc0bb40 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -2378,7 +2378,7 @@ keep_going:						/* We will come back to here until there is
 		ch = &conn->connhost[conn->whichhost];
 
 		/* Initialize hint structure */
-		MemSet(&hint, 0, sizeof(hint));
+		memset(&hint, 0, sizeof(hint));
 		hint.ai_socktype = SOCK_STREAM;
 		conn->addrlist_family = hint.ai_family = AF_UNSPEC;
 
@@ -3977,7 +3977,7 @@ makeEmptyPGconn(void)
 		return conn;
 
 	/* Zero all pointers and booleans */
-	MemSet(conn, 0, sizeof(PGconn));
+	memset(conn, 0, sizeof(PGconn));
 
 	/* install default notice hooks */
 	conn->noticeHooks.noticeRec = defaultNoticeReceiver;
@@ -5545,7 +5545,7 @@ conninfo_init(PQExpBuffer errorMessage)
 		memcpy(opt_dest, cur_opt, sizeof(PQconninfoOption));
 		opt_dest++;
 	}
-	MemSet(opt_dest, 0, sizeof(PQconninfoOption));
+	memset(opt_dest, 0, sizeof(PQconninfoOption));
 
 	return options;
 }
diff --git a/src/interfaces/libpq/fe-lobj.c b/src/interfaces/libpq/fe-lobj.c
index 075a5ed85b..b59df84baf 100644
--- a/src/interfaces/libpq/fe-lobj.c
+++ b/src/interfaces/libpq/fe-lobj.c
@@ -884,7 +884,7 @@ lo_initialize(PGconn *conn)
 							 libpq_gettext("out of memory\n"));
 		return -1;
 	}
-	MemSet((char *) lobjfuncs, 0, sizeof(PGlobjfuncs));
+	memset((char *) lobjfuncs, 0, sizeof(PGlobjfuncs));
 
 	/*
 	 * Execute the query to get all the functions at once.  (Not all of them
diff --git a/src/interfaces/libpq/fe-protocol3.c b/src/interfaces/libpq/fe-protocol3.c
index 10c76daf6e..a8321fae0a 100644
--- a/src/interfaces/libpq/fe-protocol3.c
+++ b/src/interfaces/libpq/fe-protocol3.c
@@ -557,7 +557,7 @@ getRowDescriptions(PGconn *conn, int msgLength)
 			errmsg = NULL;		/* means "out of memory", see below */
 			goto advance_and_error;
 		}
-		MemSet(result->attDescs, 0, nfields * sizeof(PGresAttDesc));
+		memset(result->attDescs, 0, nfields * sizeof(PGresAttDesc));
 	}
 
 	/* result->binary is true only if ALL columns are binary */
@@ -703,7 +703,7 @@ getParamDescriptions(PGconn *conn, int msgLength)
 			pqResultAlloc(result, nparams * sizeof(PGresParamDesc), true);
 		if (!result->paramDescs)
 			goto advance_and_error;
-		MemSet(result->paramDescs, 0, nparams * sizeof(PGresParamDesc));
+		memset(result->paramDescs, 0, nparams * sizeof(PGresParamDesc));
 	}
 
 	/* get parameter info */
@@ -1529,7 +1529,7 @@ getCopyStart(PGconn *conn, ExecStatusType copytype)
 			pqResultAlloc(result, nfields * sizeof(PGresAttDesc), true);
 		if (!result->attDescs)
 			goto failure;
-		MemSet(result->attDescs, 0, nfields * sizeof(PGresAttDesc));
+		memset(result->attDescs, 0, nfields * sizeof(PGresAttDesc));
 	}
 
 	for (i = 0; i < nfields; i++)
diff --git a/src/pl/plperl/plperl.c b/src/pl/plperl/plperl.c
index edb93ec1c4..25d98a81c8 100644
--- a/src/pl/plperl/plperl.c
+++ b/src/pl/plperl/plperl.c
@@ -1844,7 +1844,7 @@ plperl_call_handler(PG_FUNCTION_ARGS)
 	plperl_call_data this_call_data;
 
 	/* Initialize current-call status record */
-	MemSet(&this_call_data, 0, sizeof(this_call_data));
+	memset(&this_call_data, 0, sizeof(this_call_data));
 	this_call_data.fcinfo = fcinfo;
 
 	PG_TRY();
@@ -1890,7 +1890,7 @@ plperl_inline_handler(PG_FUNCTION_ARGS)
 	ErrorContextCallback pl_error_context;
 
 	/* Initialize current-call status record */
-	MemSet(&this_call_data, 0, sizeof(this_call_data));
+	memset(&this_call_data, 0, sizeof(this_call_data));
 
 	/* Set up a callback for error reporting */
 	pl_error_context.callback = plperl_inline_callback;
@@ -1903,9 +1903,9 @@ plperl_inline_handler(PG_FUNCTION_ARGS)
 	 * plperl_call_perl_func().  In particular note that this sets things up
 	 * with no arguments passed, and a result type of VOID.
 	 */
-	MemSet(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
-	MemSet(&flinfo, 0, sizeof(flinfo));
-	MemSet(&desc, 0, sizeof(desc));
+	memset(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
+	memset(&flinfo, 0, sizeof(flinfo));
+	memset(&desc, 0, sizeof(desc));
 	fake_fcinfo->flinfo = &flinfo;
 	flinfo.fn_oid = InvalidOid;
 	flinfo.fn_mcxt = CurrentMemoryContext;
diff --git a/src/pl/plpgsql/src/pl_comp.c b/src/pl/plpgsql/src/pl_comp.c
index b791c23f06..d7053ad914 100644
--- a/src/pl/plpgsql/src/pl_comp.c
+++ b/src/pl/plpgsql/src/pl_comp.c
@@ -2455,7 +2455,7 @@ compute_function_hashkey(FunctionCallInfo fcinfo,
 						 bool forValidator)
 {
 	/* Make sure any unused bytes of the struct are zero */
-	MemSet(hashkey, 0, sizeof(PLpgSQL_func_hashkey));
+	memset(hashkey, 0, sizeof(PLpgSQL_func_hashkey));
 
 	/* get function OID */
 	hashkey->funcOid = fcinfo->flinfo->fn_oid;
diff --git a/src/pl/plpgsql/src/pl_handler.c b/src/pl/plpgsql/src/pl_handler.c
index 190d286f1c..d51de407e1 100644
--- a/src/pl/plpgsql/src/pl_handler.c
+++ b/src/pl/plpgsql/src/pl_handler.c
@@ -340,8 +340,8 @@ plpgsql_inline_handler(PG_FUNCTION_ARGS)
 	 * plpgsql_exec_function().  In particular note that this sets things up
 	 * with no arguments passed.
 	 */
-	MemSet(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
-	MemSet(&flinfo, 0, sizeof(flinfo));
+	memset(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
+	memset(&flinfo, 0, sizeof(flinfo));
 	fake_fcinfo->flinfo = &flinfo;
 	flinfo.fn_oid = InvalidOid;
 	flinfo.fn_mcxt = CurrentMemoryContext;
@@ -517,20 +517,20 @@ plpgsql_validator(PG_FUNCTION_ARGS)
 		 * Set up a fake fcinfo with just enough info to satisfy
 		 * plpgsql_compile().
 		 */
-		MemSet(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
-		MemSet(&flinfo, 0, sizeof(flinfo));
+		memset(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
+		memset(&flinfo, 0, sizeof(flinfo));
 		fake_fcinfo->flinfo = &flinfo;
 		flinfo.fn_oid = funcoid;
 		flinfo.fn_mcxt = CurrentMemoryContext;
 		if (is_dml_trigger)
 		{
-			MemSet(&trigdata, 0, sizeof(trigdata));
+			memset(&trigdata, 0, sizeof(trigdata));
 			trigdata.type = T_TriggerData;
 			fake_fcinfo->context = (Node *) &trigdata;
 		}
 		else if (is_event_trigger)
 		{
-			MemSet(&etrigdata, 0, sizeof(etrigdata));
+			memset(&etrigdata, 0, sizeof(etrigdata));
 			etrigdata.type = T_EventTriggerData;
 			fake_fcinfo->context = (Node *) &etrigdata;
 		}
diff --git a/src/pl/plpython/plpy_main.c b/src/pl/plpython/plpy_main.c
index 0bce106495..dc707da034 100644
--- a/src/pl/plpython/plpy_main.c
+++ b/src/pl/plpython/plpy_main.c
@@ -277,13 +277,13 @@ plpython3_inline_handler(PG_FUNCTION_ARGS)
 	if (SPI_connect_ext(codeblock->atomic ? 0 : SPI_OPT_NONATOMIC) != SPI_OK_CONNECT)
 		elog(ERROR, "SPI_connect failed");
 
-	MemSet(fcinfo, 0, SizeForFunctionCallInfo(0));
-	MemSet(&flinfo, 0, sizeof(flinfo));
+	memset(fcinfo, 0, SizeForFunctionCallInfo(0));
+	memset(&flinfo, 0, sizeof(flinfo));
 	fake_fcinfo->flinfo = &flinfo;
 	flinfo.fn_oid = InvalidOid;
 	flinfo.fn_mcxt = CurrentMemoryContext;
 
-	MemSet(&proc, 0, sizeof(PLyProcedure));
+	memset(&proc, 0, sizeof(PLyProcedure));
 	proc.mcxt = AllocSetContextCreate(TopMemoryContext,
 									  "__plpython_inline_block",
 									  ALLOCSET_DEFAULT_SIZES);
diff --git a/src/port/snprintf.c b/src/port/snprintf.c
index abb1c59770..2e929e4e8e 100644
--- a/src/port/snprintf.c
+++ b/src/port/snprintf.c
@@ -761,7 +761,7 @@ find_arguments(const char *format, va_list args,
 
 	/* Initialize to "no dollar arguments known" */
 	last_dollar = 0;
-	MemSet(argtypes, 0, sizeof(argtypes));
+	memset(argtypes, 0, sizeof(argtypes));
 
 	/*
 	 * This loop must accept the same format strings as the one in dopr().
diff --git a/src/test/modules/test_predtest/test_predtest.c b/src/test/modules/test_predtest/test_predtest.c
index 3b19e0eadc..1d2b1d4956 100644
--- a/src/test/modules/test_predtest/test_predtest.c
+++ b/src/test/modules/test_predtest/test_predtest.c
@@ -204,7 +204,7 @@ test_predtest(PG_FUNCTION_ARGS)
 					   "w_r_holds", BOOLOID, -1, 0);
 	tupdesc = BlessTupleDesc(tupdesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(nulls, 0, sizeof(nulls));
 	values[0] = BoolGetDatum(strong_implied_by);
 	values[1] = BoolGetDatum(weak_implied_by);
 	values[2] = BoolGetDatum(strong_refuted_by);
diff --git a/src/test/regress/regress.c b/src/test/regress/regress.c
index ba3532a51e..e13db0d683 100644
--- a/src/test/regress/regress.c
+++ b/src/test/regress/regress.c
@@ -1199,7 +1199,7 @@ test_enc_conversion(PG_FUNCTION_ARGS)
 		pfree(dst);
 	}
 
-	MemSet(nulls, 0, sizeof(nulls));
+	memset(nulls, 0, sizeof(nulls));
 	values[0] = Int32GetDatum(convertedbytes);
 	values[1] = PointerGetDatum(retval);
 	tuple = heap_form_tuple(tupdesc, values, nulls);

diff --git a/src/backend/commands/copyfromparse.c b/src/backend/commands/copyfromparse.c
index 57813b3458..cef0f2c279 100644
--- a/src/backend/commands/copyfromparse.c
+++ b/src/backend/commands/copyfromparse.c
@@ -869,7 +869,7 @@ NextCopyFrom(CopyFromState cstate, ExprContext *econtext,
 
 	/* Initialize all values for row to NULL */
 	MemSet(values, 0, num_phys_attrs * sizeof(Datum));
-	MemSet(nulls, true, num_phys_attrs * sizeof(bool));
+	memset(nulls, true, num_phys_attrs * sizeof(bool));
 
 	if (!cstate->opts.binary)
 	{
diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c
index e42671722a..55ee8d455a 100644
--- a/src/backend/replication/walsender.c
+++ b/src/backend/replication/walsender.c
@@ -496,7 +496,7 @@ ReadReplicationSlot(ReadReplicationSlotCmd *cmd)
 							  INT8OID, -1, 0);
 
 	MemSet(values, 0, READ_REPLICATION_SLOT_COLS * sizeof(Datum));
-	MemSet(nulls, true, READ_REPLICATION_SLOT_COLS * sizeof(bool));
+	memset(nulls, true, READ_REPLICATION_SLOT_COLS * sizeof(bool));
 
 	LWLockAcquire(ReplicationSlotControlLock, LW_SHARED);
 	slot = SearchNamedReplicationSlot(cmd->slotname, false);
@@ -3550,7 +3550,7 @@ pg_stat_get_wal_senders(PG_FUNCTION_ARGS)
 			 * can see details. Other users only get the pid value to know
 			 * it's a walsender, but no details.
 			 */
-			MemSet(&nulls[1], true, PG_STAT_GET_WAL_SENDERS_COLS - 1);
+			memset(&nulls[1], true, PG_STAT_GET_WAL_SENDERS_COLS - 1);
 		}
 		else
 		{
diff --git a/src/backend/utils/misc/ps_status.c b/src/backend/utils/misc/ps_status.c
index ec314c03f5..ca05b180c9 100644
--- a/src/backend/utils/misc/ps_status.c
+++ b/src/backend/utils/misc/ps_status.c
@@ -393,7 +393,7 @@ set_ps_display(const char *activity)
 #ifdef PS_USE_CLOBBER_ARGV
 	/* pad unused memory; need only clobber remainder of old status string */
 	if (last_status_len > ps_buffer_cur_len)
-		MemSet(ps_buffer + ps_buffer_cur_len, PS_PADDING,
+		memset(ps_buffer + ps_buffer_cur_len, PS_PADDING,
 			   last_status_len - ps_buffer_cur_len);
 	last_status_len = ps_buffer_cur_len;
 #endif							/* PS_USE_CLOBBER_ARGV */

From fa58a89f37c920691872e60eafd171a3bd064fba Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <peter@eisentraut.org>
Date: Thu, 7 Jul 2022 12:49:10 +0200
Subject: [PATCH] WIP: Replace MemSet calls with struct initialization

---
 contrib/amcheck/verify_heapam.c               |   6 +-
 contrib/bloom/blcost.c                        |   4 +-
 contrib/pageinspect/brinfuncs.c               |   7 +-
 contrib/pageinspect/hashfuncs.c               |  16 +-
 contrib/pageinspect/heapfuncs.c               |   8 +-
 contrib/pg_prewarm/autoprewarm.c              |   6 +-
 .../pg_stat_statements/pg_stat_statements.c   |   7 +-
 contrib/pg_visibility/pg_visibility.c         |  15 +-
 contrib/pg_walinspect/pg_walinspect.c         |  25 +--
 contrib/pgstattuple/pgstatindex.c             |   3 +-
 contrib/postgres_fdw/connection.c             |   7 +-
 contrib/postgres_fdw/postgres_fdw.c           |   3 +-
 src/backend/access/transam/twophase.c         |   6 +-
 src/backend/access/transam/xlogfuncs.c        |   7 +-
 src/backend/catalog/aclchk.c                  | 146 ++++++------------
 src/backend/catalog/dependency.c              |   3 +-
 src/backend/catalog/heap.c                    |  24 +--
 src/backend/catalog/index.c                   |   4 +-
 src/backend/catalog/pg_attrdef.c              |   9 +-
 src/backend/catalog/pg_cast.c                 |   4 +-
 src/backend/catalog/pg_parameter_acl.c        |   6 +-
 src/backend/catalog/pg_publication.c          |   6 +-
 src/backend/commands/dbcommands.c             |  35 ++---
 src/backend/commands/event_trigger.c          |  11 +-
 src/backend/commands/functioncmds.c           |   7 +-
 src/backend/commands/prepare.c                |   4 +-
 src/backend/commands/tablecmds.c              |  44 ++----
 src/backend/commands/tablespace.c             |   4 +-
 src/backend/commands/typecmds.c               |   9 +-
 src/backend/commands/user.c                   |  37 ++---
 src/backend/optimizer/path/costsize.c         |   3 +-
 src/backend/parser/parse_target.c             |   3 +-
 src/backend/replication/logical/launcher.c    |   7 +-
 src/backend/replication/walsender.c           |  17 +-
 src/backend/rewrite/rewriteDefine.c           |   8 +-
 src/backend/utils/adt/acl.c                   |   4 +-
 src/backend/utils/adt/arrayfuncs.c            |   3 +-
 src/backend/utils/adt/datetime.c              |   8 +-
 src/backend/utils/adt/lockfuncs.c             |  12 +-
 src/backend/utils/adt/partitionfuncs.c        |   6 +-
 src/backend/utils/adt/pgstatfuncs.c           |  52 ++-----
 src/backend/utils/adt/selfuncs.c              |  19 +--
 src/backend/utils/adt/timestamp.c             |   8 +-
 src/backend/utils/mmgr/portalmem.c            |   4 +-
 src/bin/pg_basebackup/pg_basebackup.c         |  11 +-
 src/bin/pg_basebackup/pg_receivewal.c         |   4 +-
 src/bin/pg_basebackup/walmethods.c            |   6 +-
 src/common/ip.c                               |   4 +-
 src/port/snprintf.c                           |   7 +-
 .../modules/test_predtest/test_predtest.c     |   3 +-
 src/test/regress/regress.c                    |   3 +-
 51 files changed, 199 insertions(+), 466 deletions(-)

diff --git a/contrib/amcheck/verify_heapam.c b/contrib/amcheck/verify_heapam.c
index e488f5e234..d33f33f170 100644
--- a/contrib/amcheck/verify_heapam.c
+++ b/contrib/amcheck/verify_heapam.c
@@ -554,12 +554,10 @@ report_corruption_internal(Tuplestorestate *tupstore, TupleDesc tupdesc,
 						   BlockNumber blkno, OffsetNumber offnum,
 						   AttrNumber attnum, char *msg)
 {
-	Datum		values[HEAPCHECK_RELATION_COLS];
-	bool		nulls[HEAPCHECK_RELATION_COLS];
+	Datum		values[HEAPCHECK_RELATION_COLS] = {0};
+	bool		nulls[HEAPCHECK_RELATION_COLS] = {0};
 	HeapTuple	tuple;
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = Int64GetDatum(blkno);
 	values[1] = Int32GetDatum(offnum);
 	values[2] = Int32GetDatum(attnum);
diff --git a/contrib/bloom/blcost.c b/contrib/bloom/blcost.c
index d42e4e9628..d4b1c76303 100644
--- a/contrib/bloom/blcost.c
+++ b/contrib/bloom/blcost.c
@@ -26,9 +26,7 @@ blcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 			   double *indexPages)
 {
 	IndexOptInfo *index = path->indexinfo;
-	GenericCosts costs;
-
-	MemSet(&costs, 0, sizeof(costs));
+	GenericCosts costs = {0};
 
 	/* We have to visit all index tuples anyway */
 	costs.numIndexTuples = index->tuples;
diff --git a/contrib/pageinspect/brinfuncs.c b/contrib/pageinspect/brinfuncs.c
index 879276e6de..f4c959ecab 100644
--- a/contrib/pageinspect/brinfuncs.c
+++ b/contrib/pageinspect/brinfuncs.c
@@ -202,7 +202,7 @@ brin_page_items(PG_FUNCTION_ARGS)
 	for (;;)
 	{
 		Datum		values[7];
-		bool		nulls[7];
+		bool		nulls[7] = {0};
 
 		/*
 		 * This loop is called once for every attribute of every tuple in the
@@ -230,8 +230,6 @@ brin_page_items(PG_FUNCTION_ARGS)
 		else
 			attno++;
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		if (unusedItem)
 		{
 			values[0] = UInt16GetDatum(offset);
@@ -334,7 +332,7 @@ brin_metapage_info(PG_FUNCTION_ARGS)
 	BrinMetaPageData *meta;
 	TupleDesc	tupdesc;
 	Datum		values[4];
-	bool		nulls[4];
+	bool		nulls[4] = {0};
 	HeapTuple	htup;
 
 	if (!superuser())
@@ -354,7 +352,6 @@ brin_metapage_info(PG_FUNCTION_ARGS)
 
 	/* Extract values from the metapage */
 	meta = (BrinMetaPageData *) PageGetContents(page);
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = CStringGetTextDatum(psprintf("0x%08X", meta->brinMagic));
 	values[1] = Int32GetDatum(meta->brinVersion);
 	values[2] = Int32GetDatum(meta->pagesPerRange);
diff --git a/contrib/pageinspect/hashfuncs.c b/contrib/pageinspect/hashfuncs.c
index 5287dbe1a3..81815392d7 100644
--- a/contrib/pageinspect/hashfuncs.c
+++ b/contrib/pageinspect/hashfuncs.c
@@ -238,7 +238,7 @@ hash_page_stats(PG_FUNCTION_ARGS)
 	Page		page;
 	int			j;
 	Datum		values[9];
-	bool		nulls[9];
+	bool		nulls[9] = {0};
 	HashPageStat stat;
 	HeapTuple	tuple;
 	TupleDesc	tupleDesc;
@@ -261,8 +261,6 @@ hash_page_stats(PG_FUNCTION_ARGS)
 		elog(ERROR, "return type must be a row type");
 	tupleDesc = BlessTupleDesc(tupleDesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
-
 	j = 0;
 	values[j++] = Int32GetDatum(stat.live_items);
 	values[j++] = Int32GetDatum(stat.dead_items);
@@ -303,7 +301,7 @@ hash_page_items(PG_FUNCTION_ARGS)
 	Page		page;
 	Datum		result;
 	Datum		values[3];
-	bool		nulls[3];
+	bool		nulls[3] = {0};
 	uint32		hashkey;
 	HeapTuple	tuple;
 	FuncCallContext *fctx;
@@ -361,8 +359,6 @@ hash_page_items(PG_FUNCTION_ARGS)
 
 		itup = (IndexTuple) PageGetItem(uargs->page, id);
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		j = 0;
 		values[j++] = Int32GetDatum((int32) uargs->offset);
 		values[j++] = PointerGetDatum(&itup->t_tid);
@@ -409,7 +405,7 @@ hash_bitmap_info(PG_FUNCTION_ARGS)
 	int			i,
 				j;
 	Datum		values[3];
-	bool		nulls[3];
+	bool		nulls[3] = {0};
 	uint32	   *freep;
 
 	if (!superuser())
@@ -495,8 +491,6 @@ hash_bitmap_info(PG_FUNCTION_ARGS)
 		elog(ERROR, "return type must be a row type");
 	tupleDesc = BlessTupleDesc(tupleDesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
-
 	j = 0;
 	values[j++] = Int64GetDatum((int64) bitmapblkno);
 	values[j++] = Int32GetDatum(bitmapbit);
@@ -526,7 +520,7 @@ hash_metapage_info(PG_FUNCTION_ARGS)
 	int			i,
 				j;
 	Datum		values[16];
-	bool		nulls[16];
+	bool		nulls[16] = {0};
 	Datum		spares[HASH_MAX_SPLITPOINTS];
 	Datum		mapp[HASH_MAX_BITMAPS];
 
@@ -544,8 +538,6 @@ hash_metapage_info(PG_FUNCTION_ARGS)
 
 	metad = HashPageGetMeta(page);
 
-	MemSet(nulls, 0, sizeof(nulls));
-
 	j = 0;
 	values[j++] = Int64GetDatum((int64) metad->hashm_magic);
 	values[j++] = Int64GetDatum((int64) metad->hashm_version);
diff --git a/contrib/pageinspect/heapfuncs.c b/contrib/pageinspect/heapfuncs.c
index a654234c6b..2ff70405cf 100644
--- a/contrib/pageinspect/heapfuncs.c
+++ b/contrib/pageinspect/heapfuncs.c
@@ -507,8 +507,8 @@ Datum
 heap_tuple_infomask_flags(PG_FUNCTION_ARGS)
 {
 #define HEAP_TUPLE_INFOMASK_COLS 2
-	Datum		values[HEAP_TUPLE_INFOMASK_COLS];
-	bool		nulls[HEAP_TUPLE_INFOMASK_COLS];
+	Datum		values[HEAP_TUPLE_INFOMASK_COLS] = {0};
+	bool		nulls[HEAP_TUPLE_INFOMASK_COLS] = {0};
 	uint16		t_infomask = PG_GETARG_INT16(0);
 	uint16		t_infomask2 = PG_GETARG_INT16(1);
 	int			cnt = 0;
@@ -530,10 +530,6 @@ heap_tuple_infomask_flags(PG_FUNCTION_ARGS)
 	bitcnt = pg_popcount((const char *) &t_infomask, sizeof(uint16)) +
 		pg_popcount((const char *) &t_infomask2, sizeof(uint16));
 
-	/* Initialize values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* If no flags, return a set of empty arrays */
 	if (bitcnt <= 0)
 	{
diff --git a/contrib/pg_prewarm/autoprewarm.c b/contrib/pg_prewarm/autoprewarm.c
index 13eee4a137..ee20e9b085 100644
--- a/contrib/pg_prewarm/autoprewarm.c
+++ b/contrib/pg_prewarm/autoprewarm.c
@@ -814,12 +814,11 @@ apw_detach_shmem(int code, Datum arg)
 static void
 apw_start_leader_worker(void)
 {
-	BackgroundWorker worker;
+	BackgroundWorker worker = {0};
 	BackgroundWorkerHandle *handle;
 	BgwHandleStatus status;
 	pid_t		pid;
 
-	MemSet(&worker, 0, sizeof(BackgroundWorker));
 	worker.bgw_flags = BGWORKER_SHMEM_ACCESS;
 	worker.bgw_start_time = BgWorkerStart_ConsistentState;
 	strcpy(worker.bgw_library_name, "pg_prewarm");
@@ -856,10 +855,9 @@ apw_start_leader_worker(void)
 static void
 apw_start_database_worker(void)
 {
-	BackgroundWorker worker;
+	BackgroundWorker worker = {0};
 	BackgroundWorkerHandle *handle;
 
-	MemSet(&worker, 0, sizeof(BackgroundWorker));
 	worker.bgw_flags =
 		BGWORKER_SHMEM_ACCESS | BGWORKER_BACKEND_DATABASE_CONNECTION;
 	worker.bgw_start_time = BgWorkerStart_ConsistentState;
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index 4acfddcdb8..b4d4231dc6 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -1854,8 +1854,8 @@ pg_stat_statements_info(PG_FUNCTION_ARGS)
 {
 	pgssGlobalStats stats;
 	TupleDesc	tupdesc;
-	Datum		values[PG_STAT_STATEMENTS_INFO_COLS];
-	bool		nulls[PG_STAT_STATEMENTS_INFO_COLS];
+	Datum		values[PG_STAT_STATEMENTS_INFO_COLS] = {0};
+	bool		nulls[PG_STAT_STATEMENTS_INFO_COLS] = {0};
 
 	if (!pgss || !pgss_hash)
 		ereport(ERROR,
@@ -1866,9 +1866,6 @@ pg_stat_statements_info(PG_FUNCTION_ARGS)
 	if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
 		elog(ERROR, "return type must be a row type");
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* Read global statistics for pg_stat_statements */
 	{
 		volatile pgssSharedState *s = (volatile pgssSharedState *) pgss;
diff --git a/contrib/pg_visibility/pg_visibility.c b/contrib/pg_visibility/pg_visibility.c
index 4e2e9ea9bb..a95f73ec79 100644
--- a/contrib/pg_visibility/pg_visibility.c
+++ b/contrib/pg_visibility/pg_visibility.c
@@ -75,7 +75,7 @@ pg_visibility_map(PG_FUNCTION_ARGS)
 	Buffer		vmbuffer = InvalidBuffer;
 	TupleDesc	tupdesc;
 	Datum		values[2];
-	bool		nulls[2];
+	bool		nulls[2] = {0};
 
 	rel = relation_open(relid, AccessShareLock);
 
@@ -88,7 +88,6 @@ pg_visibility_map(PG_FUNCTION_ARGS)
 				 errmsg("invalid block number")));
 
 	tupdesc = pg_visibility_tupdesc(false, false);
-	MemSet(nulls, 0, sizeof(nulls));
 
 	mapbits = (int32) visibilitymap_get_status(rel, blkno, &vmbuffer);
 	if (vmbuffer != InvalidBuffer)
@@ -117,7 +116,7 @@ pg_visibility(PG_FUNCTION_ARGS)
 	Page		page;
 	TupleDesc	tupdesc;
 	Datum		values[3];
-	bool		nulls[3];
+	bool		nulls[3] = {0};
 
 	rel = relation_open(relid, AccessShareLock);
 
@@ -130,7 +129,6 @@ pg_visibility(PG_FUNCTION_ARGS)
 				 errmsg("invalid block number")));
 
 	tupdesc = pg_visibility_tupdesc(false, true);
-	MemSet(nulls, 0, sizeof(nulls));
 
 	mapbits = (int32) visibilitymap_get_status(rel, blkno, &vmbuffer);
 	if (vmbuffer != InvalidBuffer)
@@ -188,10 +186,9 @@ pg_visibility_map_rel(PG_FUNCTION_ARGS)
 	if (info->next < info->count)
 	{
 		Datum		values[3];
-		bool		nulls[3];
+		bool		nulls[3] = {0};
 		HeapTuple	tuple;
 
-		MemSet(nulls, 0, sizeof(nulls));
 		values[0] = Int64GetDatum(info->next);
 		values[1] = BoolGetDatum((info->bits[info->next] & (1 << 0)) != 0);
 		values[2] = BoolGetDatum((info->bits[info->next] & (1 << 1)) != 0);
@@ -233,10 +230,9 @@ pg_visibility_rel(PG_FUNCTION_ARGS)
 	if (info->next < info->count)
 	{
 		Datum		values[4];
-		bool		nulls[4];
+		bool		nulls[4] = {0};
 		HeapTuple	tuple;
 
-		MemSet(nulls, 0, sizeof(nulls));
 		values[0] = Int64GetDatum(info->next);
 		values[1] = BoolGetDatum((info->bits[info->next] & (1 << 0)) != 0);
 		values[2] = BoolGetDatum((info->bits[info->next] & (1 << 1)) != 0);
@@ -266,7 +262,7 @@ pg_visibility_map_summary(PG_FUNCTION_ARGS)
 	int64		all_frozen = 0;
 	TupleDesc	tupdesc;
 	Datum		values[2];
-	bool		nulls[2];
+	bool		nulls[2] = {0};
 
 	rel = relation_open(relid, AccessShareLock);
 
@@ -300,7 +296,6 @@ pg_visibility_map_summary(PG_FUNCTION_ARGS)
 	TupleDescInitEntry(tupdesc, (AttrNumber) 2, "all_frozen", INT8OID, -1, 0);
 	tupdesc = BlessTupleDesc(tupdesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = Int64GetDatum(all_visible);
 	values[1] = Int64GetDatum(all_frozen);
 
diff --git a/contrib/pg_walinspect/pg_walinspect.c b/contrib/pg_walinspect/pg_walinspect.c
index a082dfb331..9081787634 100644
--- a/contrib/pg_walinspect/pg_walinspect.c
+++ b/contrib/pg_walinspect/pg_walinspect.c
@@ -229,8 +229,8 @@ pg_get_wal_record_info(PG_FUNCTION_ARGS)
 {
 #define PG_GET_WAL_RECORD_INFO_COLS 11
 	Datum		result;
-	Datum		values[PG_GET_WAL_RECORD_INFO_COLS];
-	bool		nulls[PG_GET_WAL_RECORD_INFO_COLS];
+	Datum		values[PG_GET_WAL_RECORD_INFO_COLS] = {0};
+	bool		nulls[PG_GET_WAL_RECORD_INFO_COLS] = {0};
 	XLogRecPtr	lsn;
 	XLogRecPtr	curr_lsn;
 	XLogRecPtr	first_record;
@@ -266,9 +266,6 @@ pg_get_wal_record_info(PG_FUNCTION_ARGS)
 				 errmsg("could not read WAL at %X/%X",
 						LSN_FORMAT_ARGS(first_record))));
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	GetWALRecordInfo(xlogreader, first_record, values, nulls,
 					 PG_GET_WAL_RECORD_INFO_COLS);
 
@@ -334,8 +331,8 @@ GetWALRecordsInfo(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
 	XLogRecPtr	first_record;
 	XLogReaderState *xlogreader;
 	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
-	Datum		values[PG_GET_WAL_RECORDS_INFO_COLS];
-	bool		nulls[PG_GET_WAL_RECORDS_INFO_COLS];
+	Datum		values[PG_GET_WAL_RECORDS_INFO_COLS] = {0};
+	bool		nulls[PG_GET_WAL_RECORDS_INFO_COLS] = {0};
 
 	SetSingleFuncCall(fcinfo, 0);
 
@@ -343,9 +340,6 @@ GetWALRecordsInfo(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
 
 	Assert(xlogreader);
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	while (ReadNextXLogRecord(xlogreader, first_record) &&
 		   xlogreader->EndRecPtr <= end_lsn)
 	{
@@ -556,17 +550,15 @@ GetWalStats(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
 #define PG_GET_WAL_STATS_COLS 9
 	XLogRecPtr	first_record;
 	XLogReaderState *xlogreader;
-	XLogStats	stats;
+	XLogStats	stats = {0};
 	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
-	Datum		values[PG_GET_WAL_STATS_COLS];
-	bool		nulls[PG_GET_WAL_STATS_COLS];
+	Datum		values[PG_GET_WAL_STATS_COLS] = {0};
+	bool		nulls[PG_GET_WAL_STATS_COLS] = {0};
 
 	SetSingleFuncCall(fcinfo, 0);
 
 	xlogreader = InitXLogReaderState(start_lsn, &first_record);
 
-	MemSet(&stats, 0, sizeof(stats));
-
 	while (ReadNextXLogRecord(xlogreader, first_record) &&
 		   xlogreader->EndRecPtr <= end_lsn)
 	{
@@ -578,9 +570,6 @@ GetWalStats(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
 	pfree(xlogreader->private_data);
 	XLogReaderFree(xlogreader);
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	GetXLogSummaryStats(&stats, rsinfo, values, nulls,
 						PG_GET_WAL_STATS_COLS,
 						stats_per_record);
diff --git a/contrib/pgstattuple/pgstatindex.c b/contrib/pgstattuple/pgstatindex.c
index e1048e47ff..d69ac1c93d 100644
--- a/contrib/pgstattuple/pgstatindex.c
+++ b/contrib/pgstattuple/pgstatindex.c
@@ -575,7 +575,7 @@ pgstathashindex(PG_FUNCTION_ARGS)
 	HeapTuple	tuple;
 	TupleDesc	tupleDesc;
 	Datum		values[8];
-	bool		nulls[8];
+	bool		nulls[8] = {0};
 	Buffer		metabuf;
 	HashMetaPage metap;
 	float8		free_percent;
@@ -697,7 +697,6 @@ pgstathashindex(PG_FUNCTION_ARGS)
 	/*
 	 * Build and return the tuple
 	 */
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = Int32GetDatum(stats.version);
 	values[1] = Int64GetDatum((int64) stats.bucket_pages);
 	values[2] = Int64GetDatum((int64) stats.overflow_pages);
diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c
index cffb6f8310..939d114f02 100644
--- a/contrib/postgres_fdw/connection.c
+++ b/contrib/postgres_fdw/connection.c
@@ -1678,8 +1678,8 @@ postgres_fdw_get_connections(PG_FUNCTION_ARGS)
 	while ((entry = (ConnCacheEntry *) hash_seq_search(&scan)))
 	{
 		ForeignServer *server;
-		Datum		values[POSTGRES_FDW_GET_CONNECTIONS_COLS];
-		bool		nulls[POSTGRES_FDW_GET_CONNECTIONS_COLS];
+		Datum		values[POSTGRES_FDW_GET_CONNECTIONS_COLS] = {0};
+		bool		nulls[POSTGRES_FDW_GET_CONNECTIONS_COLS] = {0};
 
 		/* We only look for open remote connections */
 		if (!entry->conn)
@@ -1687,9 +1687,6 @@ postgres_fdw_get_connections(PG_FUNCTION_ARGS)
 
 		server = GetForeignServerExtended(entry->serverid, FSV_MISSING_OK);
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		/*
 		 * The foreign server may have been dropped in current explicit
 		 * transaction. It is not possible to drop the server from another
diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c
index 955a428e3d..cfac539008 100644
--- a/contrib/postgres_fdw/postgres_fdw.c
+++ b/contrib/postgres_fdw/postgres_fdw.c
@@ -3307,7 +3307,7 @@ estimate_path_cost_size(PlannerInfo *root,
 		{
 			RelOptInfo *outerrel = fpinfo->outerrel;
 			PgFdwRelationInfo *ofpinfo;
-			AggClauseCosts aggcosts;
+			AggClauseCosts aggcosts = {0};
 			double		input_rows;
 			int			numGroupCols;
 			double		numGroups = 1;
@@ -3331,7 +3331,6 @@ estimate_path_cost_size(PlannerInfo *root,
 			input_rows = ofpinfo->rows;
 
 			/* Collect statistics about aggregates for estimating costs. */
-			MemSet(&aggcosts, 0, sizeof(AggClauseCosts));
 			if (root->parse->hasAggs)
 			{
 				get_agg_clause_costs(root, AGGSPLIT_SIMPLE, &aggcosts);
diff --git a/src/backend/access/transam/twophase.c b/src/backend/access/transam/twophase.c
index 41b31c5c6f..803d169f57 100644
--- a/src/backend/access/transam/twophase.c
+++ b/src/backend/access/transam/twophase.c
@@ -780,8 +780,8 @@ pg_prepared_xact(PG_FUNCTION_ARGS)
 	{
 		GlobalTransaction gxact = &status->array[status->currIdx++];
 		PGPROC	   *proc = &ProcGlobal->allProcs[gxact->pgprocno];
-		Datum		values[5];
-		bool		nulls[5];
+		Datum		values[5] = {0};
+		bool		nulls[5] = {0};
 		HeapTuple	tuple;
 		Datum		result;
 
@@ -791,8 +791,6 @@ pg_prepared_xact(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
 
 		values[0] = TransactionIdGetDatum(proc->xid);
 		values[1] = CStringGetTextDatum(gxact->gid);
diff --git a/src/backend/access/transam/xlogfuncs.c b/src/backend/access/transam/xlogfuncs.c
index 02bd919ff6..61e0f4a29c 100644
--- a/src/backend/access/transam/xlogfuncs.c
+++ b/src/backend/access/transam/xlogfuncs.c
@@ -106,8 +106,8 @@ pg_backup_stop(PG_FUNCTION_ARGS)
 {
 #define PG_STOP_BACKUP_V2_COLS 3
 	TupleDesc	tupdesc;
-	Datum		values[PG_STOP_BACKUP_V2_COLS];
-	bool		nulls[PG_STOP_BACKUP_V2_COLS];
+	Datum		values[PG_STOP_BACKUP_V2_COLS] = {0};
+	bool		nulls[PG_STOP_BACKUP_V2_COLS] = {0};
 
 	bool		waitforarchive = PG_GETARG_BOOL(0);
 	XLogRecPtr	stoppoint;
@@ -117,9 +117,6 @@ pg_backup_stop(PG_FUNCTION_ARGS)
 	if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
 		elog(ERROR, "return type must be a row type");
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	if (status != SESSION_BACKUP_RUNNING)
 		ereport(ERROR,
 				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
diff --git a/src/backend/catalog/aclchk.c b/src/backend/catalog/aclchk.c
index 5f1726c095..17ff617fba 100644
--- a/src/backend/catalog/aclchk.c
+++ b/src/backend/catalog/aclchk.c
@@ -1188,9 +1188,6 @@ SetDefaultACL(InternalDefaultACL *iacls)
 	Acl		   *old_acl;
 	Acl		   *new_acl;
 	HeapTuple	newtuple;
-	Datum		values[Natts_pg_default_acl];
-	bool		nulls[Natts_pg_default_acl];
-	bool		replaces[Natts_pg_default_acl];
 	int			noldmembers;
 	int			nnewmembers;
 	Oid		   *oldmembers;
@@ -1341,13 +1338,11 @@ SetDefaultACL(InternalDefaultACL *iacls)
 	}
 	else
 	{
+		Datum		values[Natts_pg_default_acl] = {0};
+		bool		nulls[Natts_pg_default_acl] = {0};
+		bool		replaces[Natts_pg_default_acl] = {0};
 		Oid			defAclOid;
 
-		/* Prepare to insert or update pg_default_acl entry */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		if (isNew)
 		{
 			/* insert new entry */
@@ -1662,9 +1657,9 @@ ExecGrant_Attribute(InternalGrant *istmt, Oid relOid, const char *relname,
 	AclMode		avail_goptions;
 	bool		need_update;
 	HeapTuple	newtuple;
-	Datum		values[Natts_pg_attribute];
-	bool		nulls[Natts_pg_attribute];
-	bool		replaces[Natts_pg_attribute];
+	Datum		values[Natts_pg_attribute] = {0};
+	bool		nulls[Natts_pg_attribute] = {0};
+	bool		replaces[Natts_pg_attribute] = {0};
 	int			noldmembers;
 	int			nnewmembers;
 	Oid		   *oldmembers;
@@ -1745,9 +1740,6 @@ ExecGrant_Attribute(InternalGrant *istmt, Oid relOid, const char *relname,
 	nnewmembers = aclmembers(new_acl, &newmembers);
 
 	/* finished building new ACL value, now insert it */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, false, sizeof(nulls));
-	MemSet(replaces, false, sizeof(replaces));
 
 	/*
 	 * If the updated ACL is empty, we can set attacl to null, and maybe even
@@ -1975,9 +1967,9 @@ ExecGrant_Relation(InternalGrant *istmt)
 			Acl		   *new_acl;
 			Oid			grantorId;
 			HeapTuple	newtuple;
-			Datum		values[Natts_pg_class];
-			bool		nulls[Natts_pg_class];
-			bool		replaces[Natts_pg_class];
+			Datum		values[Natts_pg_class] = {0};
+			bool		nulls[Natts_pg_class] = {0};
+			bool		replaces[Natts_pg_class] = {0};
 			int			nnewmembers;
 			Oid		   *newmembers;
 			ObjectType	objtype;
@@ -2027,10 +2019,6 @@ ExecGrant_Relation(InternalGrant *istmt)
 			nnewmembers = aclmembers(new_acl, &newmembers);
 
 			/* finished building new ACL value, now insert it */
-			MemSet(values, 0, sizeof(values));
-			MemSet(nulls, false, sizeof(nulls));
-			MemSet(replaces, false, sizeof(replaces));
-
 			replaces[Anum_pg_class_relacl - 1] = true;
 			values[Anum_pg_class_relacl - 1] = PointerGetDatum(new_acl);
 
@@ -2150,9 +2138,9 @@ ExecGrant_Database(InternalGrant *istmt)
 		Oid			grantorId;
 		Oid			ownerId;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_database];
-		bool		nulls[Natts_pg_database];
-		bool		replaces[Natts_pg_database];
+		Datum		values[Natts_pg_database] = {0};
+		bool		nulls[Natts_pg_database] = {0};
+		bool		replaces[Natts_pg_database] = {0};
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2217,10 +2205,6 @@ ExecGrant_Database(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_database_datacl - 1] = true;
 		values[Anum_pg_database_datacl - 1] = PointerGetDatum(new_acl);
 
@@ -2271,9 +2255,9 @@ ExecGrant_Fdw(InternalGrant *istmt)
 		Oid			ownerId;
 		HeapTuple	tuple;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_foreign_data_wrapper];
-		bool		nulls[Natts_pg_foreign_data_wrapper];
-		bool		replaces[Natts_pg_foreign_data_wrapper];
+		Datum		values[Natts_pg_foreign_data_wrapper] = {0};
+		bool		nulls[Natts_pg_foreign_data_wrapper] = {0};
+		bool		replaces[Natts_pg_foreign_data_wrapper] = {0};
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2339,10 +2323,6 @@ ExecGrant_Fdw(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_foreign_data_wrapper_fdwacl - 1] = true;
 		values[Anum_pg_foreign_data_wrapper_fdwacl - 1] = PointerGetDatum(new_acl);
 
@@ -2398,9 +2378,9 @@ ExecGrant_ForeignServer(InternalGrant *istmt)
 		Oid			ownerId;
 		HeapTuple	tuple;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_foreign_server];
-		bool		nulls[Natts_pg_foreign_server];
-		bool		replaces[Natts_pg_foreign_server];
+		Datum		values[Natts_pg_foreign_server] = {0};
+		bool		nulls[Natts_pg_foreign_server] = {0};
+		bool		replaces[Natts_pg_foreign_server] = {0};
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2465,10 +2445,6 @@ ExecGrant_ForeignServer(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_foreign_server_srvacl - 1] = true;
 		values[Anum_pg_foreign_server_srvacl - 1] = PointerGetDatum(new_acl);
 
@@ -2523,9 +2499,9 @@ ExecGrant_Function(InternalGrant *istmt)
 		Oid			ownerId;
 		HeapTuple	tuple;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_proc];
-		bool		nulls[Natts_pg_proc];
-		bool		replaces[Natts_pg_proc];
+		Datum		values[Natts_pg_proc] = {0};
+		bool		nulls[Natts_pg_proc] = {0};
+		bool		replaces[Natts_pg_proc] = {0};
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2589,10 +2565,6 @@ ExecGrant_Function(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_proc_proacl - 1] = true;
 		values[Anum_pg_proc_proacl - 1] = PointerGetDatum(new_acl);
 
@@ -2646,9 +2618,9 @@ ExecGrant_Language(InternalGrant *istmt)
 		Oid			ownerId;
 		HeapTuple	tuple;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_language];
-		bool		nulls[Natts_pg_language];
-		bool		replaces[Natts_pg_language];
+		Datum		values[Natts_pg_language] = {0};
+		bool		nulls[Natts_pg_language] = {0};
+		bool		replaces[Natts_pg_language] = {0};
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2720,10 +2692,6 @@ ExecGrant_Language(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_language_lanacl - 1] = true;
 		values[Anum_pg_language_lanacl - 1] = PointerGetDatum(new_acl);
 
@@ -2778,9 +2746,9 @@ ExecGrant_Largeobject(InternalGrant *istmt)
 		Oid			grantorId;
 		Oid			ownerId;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_largeobject_metadata];
-		bool		nulls[Natts_pg_largeobject_metadata];
-		bool		replaces[Natts_pg_largeobject_metadata];
+		Datum		values[Natts_pg_largeobject_metadata] = {0};
+		bool		nulls[Natts_pg_largeobject_metadata] = {0};
+		bool		replaces[Natts_pg_largeobject_metadata] = {0};
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2858,10 +2826,6 @@ ExecGrant_Largeobject(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_largeobject_metadata_lomacl - 1] = true;
 		values[Anum_pg_largeobject_metadata_lomacl - 1]
 			= PointerGetDatum(new_acl);
@@ -2917,9 +2881,9 @@ ExecGrant_Namespace(InternalGrant *istmt)
 		Oid			ownerId;
 		HeapTuple	tuple;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_namespace];
-		bool		nulls[Natts_pg_namespace];
-		bool		replaces[Natts_pg_namespace];
+		Datum		values[Natts_pg_namespace] = {0};
+		bool		nulls[Natts_pg_namespace] = {0};
+		bool		replaces[Natts_pg_namespace] = {0};
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2984,10 +2948,6 @@ ExecGrant_Namespace(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_namespace_nspacl - 1] = true;
 		values[Anum_pg_namespace_nspacl - 1] = PointerGetDatum(new_acl);
 
@@ -3040,9 +3000,9 @@ ExecGrant_Tablespace(InternalGrant *istmt)
 		Oid			grantorId;
 		Oid			ownerId;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_tablespace];
-		bool		nulls[Natts_pg_tablespace];
-		bool		replaces[Natts_pg_tablespace];
+		Datum		values[Natts_pg_tablespace] = {0};
+		bool		nulls[Natts_pg_tablespace] = {0};
+		bool		replaces[Natts_pg_tablespace] = {0};
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -3108,10 +3068,6 @@ ExecGrant_Tablespace(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_tablespace_spcacl - 1] = true;
 		values[Anum_pg_tablespace_spcacl - 1] = PointerGetDatum(new_acl);
 
@@ -3160,9 +3116,9 @@ ExecGrant_Type(InternalGrant *istmt)
 		Oid			grantorId;
 		Oid			ownerId;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_type];
-		bool		nulls[Natts_pg_type];
-		bool		replaces[Natts_pg_type];
+		Datum		values[Natts_pg_type] = {0};
+		bool		nulls[Natts_pg_type] = {0};
+		bool		replaces[Natts_pg_type] = {0};
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -3242,10 +3198,6 @@ ExecGrant_Type(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_type_typacl - 1] = true;
 		values[Anum_pg_type_typacl - 1] = PointerGetDatum(new_acl);
 
@@ -3384,13 +3336,9 @@ ExecGrant_Parameter(InternalGrant *istmt)
 		{
 			/* finished building new ACL value, now insert it */
 			HeapTuple	newtuple;
-			Datum		values[Natts_pg_parameter_acl];
-			bool		nulls[Natts_pg_parameter_acl];
-			bool		replaces[Natts_pg_parameter_acl];
-
-			MemSet(values, 0, sizeof(values));
-			MemSet(nulls, false, sizeof(nulls));
-			MemSet(replaces, false, sizeof(replaces));
+			Datum		values[Natts_pg_parameter_acl] = {0};
+			bool		nulls[Natts_pg_parameter_acl] = {0};
+			bool		replaces[Natts_pg_parameter_acl] = {0};
 
 			replaces[Anum_pg_parameter_acl_paracl - 1] = true;
 			values[Anum_pg_parameter_acl_paracl - 1] = PointerGetDatum(new_acl);
@@ -6419,17 +6367,13 @@ recordExtensionInitPrivWorker(Oid objoid, Oid classoid, int objsubid, Acl *new_a
 	/* If we find an entry, update it with the latest ACL. */
 	if (HeapTupleIsValid(oldtuple))
 	{
-		Datum		values[Natts_pg_init_privs];
-		bool		nulls[Natts_pg_init_privs];
-		bool		replace[Natts_pg_init_privs];
+		Datum		values[Natts_pg_init_privs] = {0};
+		bool		nulls[Natts_pg_init_privs] = {0};
+		bool		replace[Natts_pg_init_privs] = {0};
 
 		/* If we have a new ACL to set, then update the row with it. */
 		if (new_acl)
 		{
-			MemSet(values, 0, sizeof(values));
-			MemSet(nulls, false, sizeof(nulls));
-			MemSet(replace, false, sizeof(replace));
-
 			values[Anum_pg_init_privs_initprivs - 1] = PointerGetDatum(new_acl);
 			replace[Anum_pg_init_privs_initprivs - 1] = true;
 
@@ -6446,8 +6390,8 @@ recordExtensionInitPrivWorker(Oid objoid, Oid classoid, int objsubid, Acl *new_a
 	}
 	else
 	{
-		Datum		values[Natts_pg_init_privs];
-		bool		nulls[Natts_pg_init_privs];
+		Datum		values[Natts_pg_init_privs] = {0};
+		bool		nulls[Natts_pg_init_privs] = {0};
 
 		/*
 		 * Only add a new entry if the new ACL is non-NULL.
@@ -6458,8 +6402,6 @@ recordExtensionInitPrivWorker(Oid objoid, Oid classoid, int objsubid, Acl *new_a
 		if (new_acl)
 		{
 			/* No entry found, so add it. */
-			MemSet(nulls, false, sizeof(nulls));
-
 			values[Anum_pg_init_privs_objoid - 1] = ObjectIdGetDatum(objoid);
 			values[Anum_pg_init_privs_classoid - 1] = ObjectIdGetDatum(classoid);
 			values[Anum_pg_init_privs_objsubid - 1] = Int32GetDatum(objsubid);
diff --git a/src/backend/catalog/dependency.c b/src/backend/catalog/dependency.c
index de10923391..5cbd72ce10 100644
--- a/src/backend/catalog/dependency.c
+++ b/src/backend/catalog/dependency.c
@@ -1635,12 +1635,11 @@ recordDependencyOnSingleRelExpr(const ObjectAddress *depender,
 								bool reverse_self)
 {
 	find_expr_references_context context;
-	RangeTblEntry rte;
+	RangeTblEntry rte = {0};
 
 	context.addrs = new_object_addresses();
 
 	/* We gin up a rather bogus rangetable list to handle Vars */
-	MemSet(&rte, 0, sizeof(rte));
 	rte.type = T_RangeTblEntry;
 	rte.rtekind = RTE_RELATION;
 	rte.relid = relId;
diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c
index e770ea6eb8..9b03579e6e 100644
--- a/src/backend/catalog/heap.c
+++ b/src/backend/catalog/heap.c
@@ -1709,15 +1709,11 @@ RemoveAttributeById(Oid relid, AttrNumber attnum)
 		/* clear the missing value if any */
 		if (attStruct->atthasmissing)
 		{
-			Datum		valuesAtt[Natts_pg_attribute];
-			bool		nullsAtt[Natts_pg_attribute];
-			bool		replacesAtt[Natts_pg_attribute];
+			Datum		valuesAtt[Natts_pg_attribute] = {0};
+			bool		nullsAtt[Natts_pg_attribute] = {0};
+			bool		replacesAtt[Natts_pg_attribute] = {0};
 
 			/* update the tuple - set atthasmissing and attmissingval */
-			MemSet(valuesAtt, 0, sizeof(valuesAtt));
-			MemSet(nullsAtt, false, sizeof(nullsAtt));
-			MemSet(replacesAtt, false, sizeof(replacesAtt));
-
 			valuesAtt[Anum_pg_attribute_atthasmissing - 1] =
 				BoolGetDatum(false);
 			replacesAtt[Anum_pg_attribute_atthasmissing - 1] = true;
@@ -2006,9 +2002,9 @@ RelationClearMissing(Relation rel)
 void
 SetAttrMissing(Oid relid, char *attname, char *value)
 {
-	Datum		valuesAtt[Natts_pg_attribute];
-	bool		nullsAtt[Natts_pg_attribute];
-	bool		replacesAtt[Natts_pg_attribute];
+	Datum		valuesAtt[Natts_pg_attribute] = {0};
+	bool		nullsAtt[Natts_pg_attribute] = {0};
+	bool		replacesAtt[Natts_pg_attribute] = {0};
 	Datum		missingval;
 	Form_pg_attribute attStruct;
 	Relation	attrrel,
@@ -2041,10 +2037,6 @@ SetAttrMissing(Oid relid, char *attname, char *value)
 								  Int32GetDatum(attStruct->atttypmod));
 
 	/* update the tuple - set atthasmissing and attmissingval */
-	MemSet(valuesAtt, 0, sizeof(valuesAtt));
-	MemSet(nullsAtt, false, sizeof(nullsAtt));
-	MemSet(replacesAtt, false, sizeof(replacesAtt));
-
 	valuesAtt[Anum_pg_attribute_atthasmissing - 1] = BoolGetDatum(true);
 	replacesAtt[Anum_pg_attribute_atthasmissing - 1] = true;
 	valuesAtt[Anum_pg_attribute_attmissingval - 1] = missingval;
@@ -3321,7 +3313,7 @@ StorePartitionKey(Relation rel,
 	Relation	pg_partitioned_table;
 	HeapTuple	tuple;
 	Datum		values[Natts_pg_partitioned_table];
-	bool		nulls[Natts_pg_partitioned_table];
+	bool		nulls[Natts_pg_partitioned_table] = {0};
 	ObjectAddress myself;
 	ObjectAddress referenced;
 	ObjectAddresses *addrs;
@@ -3347,8 +3339,6 @@ StorePartitionKey(Relation rel,
 
 	pg_partitioned_table = table_open(PartitionedRelationId, RowExclusiveLock);
 
-	MemSet(nulls, false, sizeof(nulls));
-
 	/* Only this can ever be NULL */
 	if (!partexprDatum)
 		nulls[Anum_pg_partitioned_table_partexprs - 1] = true;
diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c
index c5d463ac55..d7192f35e3 100644
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@@ -554,7 +554,7 @@ UpdateIndexRelation(Oid indexoid,
 	Datum		exprsDatum;
 	Datum		predDatum;
 	Datum		values[Natts_pg_index];
-	bool		nulls[Natts_pg_index];
+	bool		nulls[Natts_pg_index] = {0};
 	Relation	pg_index;
 	HeapTuple	tuple;
 	int			i;
@@ -608,8 +608,6 @@ UpdateIndexRelation(Oid indexoid,
 	/*
 	 * Build a pg_index tuple
 	 */
-	MemSet(nulls, false, sizeof(nulls));
-
 	values[Anum_pg_index_indexrelid - 1] = ObjectIdGetDatum(indexoid);
 	values[Anum_pg_index_indrelid - 1] = ObjectIdGetDatum(heapoid);
 	values[Anum_pg_index_indnatts - 1] = Int16GetDatum(indexInfo->ii_NumIndexAttrs);
diff --git a/src/backend/catalog/pg_attrdef.c b/src/backend/catalog/pg_attrdef.c
index c5d4a9912e..1a14093a9a 100644
--- a/src/backend/catalog/pg_attrdef.c
+++ b/src/backend/catalog/pg_attrdef.c
@@ -111,15 +111,12 @@ StoreAttrDefault(Relation rel, AttrNumber attnum,
 		Expr	   *expr2 = (Expr *) expr;
 		EState	   *estate = NULL;
 		ExprContext *econtext;
-		Datum		valuesAtt[Natts_pg_attribute];
-		bool		nullsAtt[Natts_pg_attribute];
-		bool		replacesAtt[Natts_pg_attribute];
+		Datum		valuesAtt[Natts_pg_attribute] = {0};
+		bool		nullsAtt[Natts_pg_attribute] = {0};
+		bool		replacesAtt[Natts_pg_attribute] = {0};
 		Datum		missingval = (Datum) 0;
 		bool		missingIsNull = true;
 
-		MemSet(valuesAtt, 0, sizeof(valuesAtt));
-		MemSet(nullsAtt, false, sizeof(nullsAtt));
-		MemSet(replacesAtt, false, sizeof(replacesAtt));
 		valuesAtt[Anum_pg_attribute_atthasdef - 1] = true;
 		replacesAtt[Anum_pg_attribute_atthasdef - 1] = true;
 
diff --git a/src/backend/catalog/pg_cast.c b/src/backend/catalog/pg_cast.c
index 4857f6468d..1812bb7fcc 100644
--- a/src/backend/catalog/pg_cast.c
+++ b/src/backend/catalog/pg_cast.c
@@ -47,7 +47,7 @@ CastCreate(Oid sourcetypeid, Oid targettypeid, Oid funcid, char castcontext,
 	HeapTuple	tuple;
 	Oid			castid;
 	Datum		values[Natts_pg_cast];
-	bool		nulls[Natts_pg_cast];
+	bool		nulls[Natts_pg_cast] = {0};
 	ObjectAddress myself,
 				referenced;
 	ObjectAddresses *addrs;
@@ -78,8 +78,6 @@ CastCreate(Oid sourcetypeid, Oid targettypeid, Oid funcid, char castcontext,
 	values[Anum_pg_cast_castcontext - 1] = CharGetDatum(castcontext);
 	values[Anum_pg_cast_castmethod - 1] = CharGetDatum(castmethod);
 
-	MemSet(nulls, false, sizeof(nulls));
-
 	tuple = heap_form_tuple(RelationGetDescr(relation), values, nulls);
 
 	CatalogTupleInsert(relation, tuple);
diff --git a/src/backend/catalog/pg_parameter_acl.c b/src/backend/catalog/pg_parameter_acl.c
index 2decee909b..0570e811d1 100644
--- a/src/backend/catalog/pg_parameter_acl.c
+++ b/src/backend/catalog/pg_parameter_acl.c
@@ -74,8 +74,8 @@ ParameterAclCreate(const char *parameter)
 	Relation	rel;
 	TupleDesc	tupDesc;
 	HeapTuple	tuple;
-	Datum		values[Natts_pg_parameter_acl];
-	bool		nulls[Natts_pg_parameter_acl];
+	Datum		values[Natts_pg_parameter_acl] = {0};
+	bool		nulls[Natts_pg_parameter_acl] = {0};
 
 	/*
 	 * To prevent cluttering pg_parameter_acl with useless entries, insist
@@ -98,8 +98,6 @@ ParameterAclCreate(const char *parameter)
 	 */
 	rel = table_open(ParameterAclRelationId, RowExclusiveLock);
 	tupDesc = RelationGetDescr(rel);
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, false, sizeof(nulls));
 	parameterId = GetNewOidWithIndex(rel,
 									 ParameterAclOidIndexId,
 									 Anum_pg_parameter_acl_oid);
diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index c365de3a72..ade3bf3aca 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -1162,14 +1162,12 @@ pg_get_publication_tables(PG_FUNCTION_ARGS)
 		HeapTuple	pubtuple = NULL;
 		HeapTuple	rettuple;
 		Oid			relid = list_nth_oid(tables, funcctx->call_cntr);
-		Datum		values[NUM_PUBLICATION_TABLES_ELEM];
-		bool		nulls[NUM_PUBLICATION_TABLES_ELEM];
+		Datum		values[NUM_PUBLICATION_TABLES_ELEM] = {0};
+		bool		nulls[NUM_PUBLICATION_TABLES_ELEM] = {0};
 
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(nulls, 0, sizeof(nulls));
-		MemSet(values, 0, sizeof(values));
 
 		publication = GetPublicationByName(pubname, false);
 
diff --git a/src/backend/commands/dbcommands.c b/src/backend/commands/dbcommands.c
index 1901b434c5..099d369b2f 100644
--- a/src/backend/commands/dbcommands.c
+++ b/src/backend/commands/dbcommands.c
@@ -689,8 +689,8 @@ createdb(ParseState *pstate, const CreatedbStmt *stmt)
 	volatile Oid dst_deftablespace;
 	Relation	pg_database_rel;
 	HeapTuple	tuple;
-	Datum		new_record[Natts_pg_database];
-	bool		new_record_nulls[Natts_pg_database];
+	Datum		new_record[Natts_pg_database] = {0};
+	bool		new_record_nulls[Natts_pg_database] = {0};
 	Oid			dboid = InvalidOid;
 	Oid			datdba;
 	ListCell   *option;
@@ -1296,9 +1296,6 @@ createdb(ParseState *pstate, const CreatedbStmt *stmt)
 		   (dblocprovider != COLLPROVIDER_ICU && !dbiculocale));
 
 	/* Form tuple */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-
 	new_record[Anum_pg_database_oid - 1] = ObjectIdGetDatum(dboid);
 	new_record[Anum_pg_database_datname - 1] =
 		DirectFunctionCall1(namein, CStringGetDatum(dbname));
@@ -1822,9 +1819,6 @@ movedb(const char *dbname, const char *tblspcname)
 				newtuple;
 	Oid			src_tblspcoid,
 				dst_tblspcoid;
-	Datum		new_record[Natts_pg_database];
-	bool		new_record_nulls[Natts_pg_database];
-	bool		new_record_repl[Natts_pg_database];
 	ScanKeyData scankey;
 	SysScanDesc sysscan;
 	AclResult	aclresult;
@@ -2003,6 +1997,10 @@ movedb(const char *dbname, const char *tblspcname)
 	PG_ENSURE_ERROR_CLEANUP(movedb_failure_callback,
 							PointerGetDatum(&fparms));
 	{
+		Datum		new_record[Natts_pg_database] = {0};
+		bool		new_record_nulls[Natts_pg_database] = {0};
+		bool		new_record_repl[Natts_pg_database] = {0};
+
 		/*
 		 * Copy files from the old tablespace to the new one
 		 */
@@ -2042,10 +2040,6 @@ movedb(const char *dbname, const char *tblspcname)
 					(errcode(ERRCODE_UNDEFINED_DATABASE),
 					 errmsg("database \"%s\" does not exist", dbname)));
 
-		MemSet(new_record, 0, sizeof(new_record));
-		MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-		MemSet(new_record_repl, false, sizeof(new_record_repl));
-
 		new_record[Anum_pg_database_dattablespace - 1] = ObjectIdGetDatum(dst_tblspcoid);
 		new_record_repl[Anum_pg_database_dattablespace - 1] = true;
 
@@ -2194,9 +2188,9 @@ AlterDatabase(ParseState *pstate, AlterDatabaseStmt *stmt, bool isTopLevel)
 	DefElem    *dallowconnections = NULL;
 	DefElem    *dconnlimit = NULL;
 	DefElem    *dtablespace = NULL;
-	Datum		new_record[Natts_pg_database];
-	bool		new_record_nulls[Natts_pg_database];
-	bool		new_record_repl[Natts_pg_database];
+	Datum		new_record[Natts_pg_database] = {0};
+	bool		new_record_nulls[Natts_pg_database] = {0};
+	bool		new_record_repl[Natts_pg_database] = {0};
 
 	/* Extract options from the statement node tree */
 	foreach(option, stmt->options)
@@ -2305,10 +2299,6 @@ AlterDatabase(ParseState *pstate, AlterDatabaseStmt *stmt, bool isTopLevel)
 	/*
 	 * Build an updated tuple, perusing the information just obtained
 	 */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-	MemSet(new_record_repl, false, sizeof(new_record_repl));
-
 	if (distemplate)
 	{
 		new_record[Anum_pg_database_datistemplate - 1] = BoolGetDatum(dbistemplate);
@@ -2492,8 +2482,8 @@ AlterDatabaseOwner(const char *dbname, Oid newOwnerId)
 	if (datForm->datdba != newOwnerId)
 	{
 		Datum		repl_val[Natts_pg_database];
-		bool		repl_null[Natts_pg_database];
-		bool		repl_repl[Natts_pg_database];
+		bool		repl_null[Natts_pg_database] = {0};
+		bool		repl_repl[Natts_pg_database] = {0};
 		Acl		   *newAcl;
 		Datum		aclDatum;
 		bool		isNull;
@@ -2521,9 +2511,6 @@ AlterDatabaseOwner(const char *dbname, Oid newOwnerId)
 					(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
 					 errmsg("permission denied to change owner of database")));
 
-		memset(repl_null, false, sizeof(repl_null));
-		memset(repl_repl, false, sizeof(repl_repl));
-
 		repl_repl[Anum_pg_database_datdba - 1] = true;
 		repl_val[Anum_pg_database_datdba - 1] = ObjectIdGetDatum(newOwnerId);
 
diff --git a/src/backend/commands/event_trigger.c b/src/backend/commands/event_trigger.c
index f46f86474a..eef3e5d56e 100644
--- a/src/backend/commands/event_trigger.c
+++ b/src/backend/commands/event_trigger.c
@@ -1310,14 +1310,11 @@ pg_event_trigger_dropped_objects(PG_FUNCTION_ARGS)
 	{
 		SQLDropObject *obj;
 		int			i = 0;
-		Datum		values[12];
-		bool		nulls[12];
+		Datum		values[12] = {0};
+		bool		nulls[12] = {0};
 
 		obj = slist_container(SQLDropObject, next, iter.cur);
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		/* classid */
 		values[i++] = ObjectIdGetDatum(obj->address.classId);
 
@@ -1840,7 +1837,7 @@ pg_event_trigger_ddl_commands(PG_FUNCTION_ARGS)
 	{
 		CollectedCommand *cmd = lfirst(lc);
 		Datum		values[9];
-		bool		nulls[9];
+		bool		nulls[9] = {0};
 		ObjectAddress addr;
 		int			i = 0;
 
@@ -1858,8 +1855,6 @@ pg_event_trigger_ddl_commands(PG_FUNCTION_ARGS)
 			!OidIsValid(cmd->d.simple.address.objectId))
 			continue;
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		switch (cmd->type)
 		{
 			case SCT_Simple:
diff --git a/src/backend/commands/functioncmds.c b/src/backend/commands/functioncmds.c
index b016eecb2c..59e3af626f 100644
--- a/src/backend/commands/functioncmds.c
+++ b/src/backend/commands/functioncmds.c
@@ -1806,8 +1806,8 @@ CreateTransform(CreateTransformStmt *stmt)
 	AclResult	aclresult;
 	Form_pg_proc procstruct;
 	Datum		values[Natts_pg_transform];
-	bool		nulls[Natts_pg_transform];
-	bool		replaces[Natts_pg_transform];
+	bool		nulls[Natts_pg_transform] = {0};
+	bool		replaces[Natts_pg_transform] = {0};
 	Oid			transformid;
 	HeapTuple	tuple;
 	HeapTuple	newtuple;
@@ -1913,8 +1913,6 @@ CreateTransform(CreateTransformStmt *stmt)
 	values[Anum_pg_transform_trffromsql - 1] = ObjectIdGetDatum(fromsqlfuncid);
 	values[Anum_pg_transform_trftosql - 1] = ObjectIdGetDatum(tosqlfuncid);
 
-	MemSet(nulls, false, sizeof(nulls));
-
 	relation = table_open(TransformRelationId, RowExclusiveLock);
 
 	tuple = SearchSysCache2(TRFTYPELANG,
@@ -1931,7 +1929,6 @@ CreateTransform(CreateTransformStmt *stmt)
 							format_type_be(typeid),
 							stmt->lang)));
 
-		MemSet(replaces, false, sizeof(replaces));
 		replaces[Anum_pg_transform_trffromsql - 1] = true;
 		replaces[Anum_pg_transform_trftosql - 1] = true;
 
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 2333aae467..579825c159 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -685,12 +685,10 @@ pg_prepared_statement(PG_FUNCTION_ARGS)
 		{
 			TupleDesc	result_desc;
 			Datum		values[8];
-			bool		nulls[8];
+			bool		nulls[8] = {0};
 
 			result_desc = prep_stmt->plansource->resultDesc;
 
-			MemSet(nulls, 0, sizeof(nulls));
-
 			values[0] = CStringGetTextDatum(prep_stmt->stmt_name);
 			values[1] = CStringGetTextDatum(prep_stmt->plansource->query_string);
 			values[2] = TimestampTzGetDatum(prep_stmt->prepare_time);
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index ef5b34a312..18f7a4ae86 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -9013,15 +9013,15 @@ ATAddForeignKeyConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
 						  bool recurse, bool recursing, LOCKMODE lockmode)
 {
 	Relation	pkrel;
-	int16		pkattnum[INDEX_MAX_KEYS];
-	int16		fkattnum[INDEX_MAX_KEYS];
-	Oid			pktypoid[INDEX_MAX_KEYS];
-	Oid			fktypoid[INDEX_MAX_KEYS];
-	Oid			opclasses[INDEX_MAX_KEYS];
-	Oid			pfeqoperators[INDEX_MAX_KEYS];
-	Oid			ppeqoperators[INDEX_MAX_KEYS];
-	Oid			ffeqoperators[INDEX_MAX_KEYS];
-	int16		fkdelsetcols[INDEX_MAX_KEYS];
+	int16		pkattnum[INDEX_MAX_KEYS] = {0};
+	int16		fkattnum[INDEX_MAX_KEYS] = {0};
+	Oid			pktypoid[INDEX_MAX_KEYS] = {0};
+	Oid			fktypoid[INDEX_MAX_KEYS] = {0};
+	Oid			opclasses[INDEX_MAX_KEYS] = {0};
+	Oid			pfeqoperators[INDEX_MAX_KEYS] = {0};
+	Oid			ppeqoperators[INDEX_MAX_KEYS] = {0};
+	Oid			ffeqoperators[INDEX_MAX_KEYS] = {0};
+	int16		fkdelsetcols[INDEX_MAX_KEYS] = {0};
 	int			i;
 	int			numfks,
 				numpks,
@@ -9113,16 +9113,6 @@ ATAddForeignKeyConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
 	 * Look up the referencing attributes to make sure they exist, and record
 	 * their attnums and type OIDs.
 	 */
-	MemSet(pkattnum, 0, sizeof(pkattnum));
-	MemSet(fkattnum, 0, sizeof(fkattnum));
-	MemSet(pktypoid, 0, sizeof(pktypoid));
-	MemSet(fktypoid, 0, sizeof(fktypoid));
-	MemSet(opclasses, 0, sizeof(opclasses));
-	MemSet(pfeqoperators, 0, sizeof(pfeqoperators));
-	MemSet(ppeqoperators, 0, sizeof(ppeqoperators));
-	MemSet(ffeqoperators, 0, sizeof(ffeqoperators));
-	MemSet(fkdelsetcols, 0, sizeof(fkdelsetcols));
-
 	numfks = transformColumnNameList(RelationGetRelid(rel),
 									 fkconstraint->fk_attrs,
 									 fkattnum, fktypoid);
@@ -11498,7 +11488,7 @@ validateForeignKeyConstraint(char *conname,
 {
 	TupleTableSlot *slot;
 	TableScanDesc scan;
-	Trigger		trig;
+	Trigger		trig = {0};
 	Snapshot	snapshot;
 	MemoryContext oldcxt;
 	MemoryContext perTupCxt;
@@ -11509,7 +11499,6 @@ validateForeignKeyConstraint(char *conname,
 	/*
 	 * Build a trigger call structure; we'll need it either way.
 	 */
-	MemSet(&trig, 0, sizeof(trig));
 	trig.tgoid = InvalidOid;
 	trig.tgname = conname;
 	trig.tgenabled = TRIGGER_FIRES_ON_ORIGIN;
@@ -12783,15 +12772,11 @@ ATExecAlterColumnType(AlteredTableInfo *tab, Relation rel,
 
 			int			one = 1;
 			bool		isNull;
-			Datum		valuesAtt[Natts_pg_attribute];
-			bool		nullsAtt[Natts_pg_attribute];
-			bool		replacesAtt[Natts_pg_attribute];
+			Datum		valuesAtt[Natts_pg_attribute] = {0};
+			bool		nullsAtt[Natts_pg_attribute] = {0};
+			bool		replacesAtt[Natts_pg_attribute] = {0};
 			HeapTuple	newTup;
 
-			MemSet(valuesAtt, 0, sizeof(valuesAtt));
-			MemSet(nullsAtt, false, sizeof(nullsAtt));
-			MemSet(replacesAtt, false, sizeof(replacesAtt));
-
 			missingval = array_get_element(missingval,
 										   1,
 										   &one,
@@ -19219,7 +19204,7 @@ ATDetachCheckNoForeignKeyRefs(Relation partition)
 		HeapTuple	tuple;
 		Form_pg_constraint constrForm;
 		Relation	rel;
-		Trigger		trig;
+		Trigger		trig = {0};
 
 		tuple = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constrOid));
 		if (!HeapTupleIsValid(tuple))
@@ -19232,7 +19217,6 @@ ATDetachCheckNoForeignKeyRefs(Relation partition)
 		/* prevent data changes into the referencing table until commit */
 		rel = table_open(constrForm->conrelid, ShareLock);
 
-		MemSet(&trig, 0, sizeof(trig));
 		trig.tgoid = InvalidOid;
 		trig.tgname = NameStr(constrForm->conname);
 		trig.tgenabled = TRIGGER_FIRES_ON_ORIGIN;
diff --git a/src/backend/commands/tablespace.c b/src/backend/commands/tablespace.c
index c8bdd9992a..cb7d46089a 100644
--- a/src/backend/commands/tablespace.c
+++ b/src/backend/commands/tablespace.c
@@ -238,7 +238,7 @@ CreateTableSpace(CreateTableSpaceStmt *stmt)
 #ifdef HAVE_SYMLINK
 	Relation	rel;
 	Datum		values[Natts_pg_tablespace];
-	bool		nulls[Natts_pg_tablespace];
+	bool		nulls[Natts_pg_tablespace] = {0};
 	HeapTuple	tuple;
 	Oid			tablespaceoid;
 	char	   *location;
@@ -340,8 +340,6 @@ CreateTableSpace(CreateTableSpaceStmt *stmt)
 	 */
 	rel = table_open(TableSpaceRelationId, RowExclusiveLock);
 
-	MemSet(nulls, false, sizeof(nulls));
-
 	if (IsBinaryUpgrade)
 	{
 		/* Use binary-upgrade override for tablespace oid */
diff --git a/src/backend/commands/typecmds.c b/src/backend/commands/typecmds.c
index 4f5e7c7ccb..4f58d29aa5 100644
--- a/src/backend/commands/typecmds.c
+++ b/src/backend/commands/typecmds.c
@@ -2570,9 +2570,9 @@ AlterDomainDefault(List *names, Node *defaultRaw)
 	Relation	rel;
 	char	   *defaultValue;
 	Node	   *defaultExpr = NULL; /* NULL if no default specified */
-	Datum		new_record[Natts_pg_type];
-	bool		new_record_nulls[Natts_pg_type];
-	bool		new_record_repl[Natts_pg_type];
+	Datum		new_record[Natts_pg_type] = {0};
+	bool		new_record_nulls[Natts_pg_type] = {0};
+	bool		new_record_repl[Natts_pg_type] = {0};
 	HeapTuple	newtuple;
 	Form_pg_type typTup;
 	ObjectAddress address;
@@ -2593,9 +2593,6 @@ AlterDomainDefault(List *names, Node *defaultRaw)
 	checkDomainOwner(tup);
 
 	/* Setup new tuple */
-	MemSet(new_record, (Datum) 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-	MemSet(new_record_repl, false, sizeof(new_record_repl));
 
 	/* Store the new default into the tuple */
 	if (defaultRaw)
diff --git a/src/backend/commands/user.c b/src/backend/commands/user.c
index 984305ba31..5b24b6dcad 100644
--- a/src/backend/commands/user.c
+++ b/src/backend/commands/user.c
@@ -74,8 +74,8 @@ CreateRole(ParseState *pstate, CreateRoleStmt *stmt)
 	Relation	pg_authid_rel;
 	TupleDesc	pg_authid_dsc;
 	HeapTuple	tuple;
-	Datum		new_record[Natts_pg_authid];
-	bool		new_record_nulls[Natts_pg_authid];
+	Datum		new_record[Natts_pg_authid] = {0};
+	bool		new_record_nulls[Natts_pg_authid] = {0};
 	Oid			roleid;
 	ListCell   *item;
 	ListCell   *option;
@@ -338,12 +338,8 @@ CreateRole(ParseState *pstate, CreateRoleStmt *stmt)
 	/*
 	 * Build a tuple to insert
 	 */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-
 	new_record[Anum_pg_authid_rolname - 1] =
 		DirectFunctionCall1(namein, CStringGetDatum(stmt->role));
-
 	new_record[Anum_pg_authid_rolsuper - 1] = BoolGetDatum(issuper);
 	new_record[Anum_pg_authid_rolinherit - 1] = BoolGetDatum(inherit);
 	new_record[Anum_pg_authid_rolcreaterole - 1] = BoolGetDatum(createrole);
@@ -492,9 +488,9 @@ CreateRole(ParseState *pstate, CreateRoleStmt *stmt)
 Oid
 AlterRole(ParseState *pstate, AlterRoleStmt *stmt)
 {
-	Datum		new_record[Natts_pg_authid];
-	bool		new_record_nulls[Natts_pg_authid];
-	bool		new_record_repl[Natts_pg_authid];
+	Datum		new_record[Natts_pg_authid] = {0};
+	bool		new_record_nulls[Natts_pg_authid] = {0};
+	bool		new_record_repl[Natts_pg_authid] = {0};
 	Relation	pg_authid_rel;
 	TupleDesc	pg_authid_dsc;
 	HeapTuple	tuple,
@@ -691,9 +687,6 @@ AlterRole(ParseState *pstate, AlterRoleStmt *stmt)
 	/*
 	 * Build an updated tuple, perusing the information just obtained
 	 */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-	MemSet(new_record_repl, false, sizeof(new_record_repl));
 
 	/*
 	 * issuper/createrole/etc
@@ -1440,9 +1433,9 @@ AddRoleMems(const char *rolename, Oid roleid,
 		Oid			memberid = lfirst_oid(iditem);
 		HeapTuple	authmem_tuple;
 		HeapTuple	tuple;
-		Datum		new_record[Natts_pg_auth_members];
-		bool		new_record_nulls[Natts_pg_auth_members];
-		bool		new_record_repl[Natts_pg_auth_members];
+		Datum		new_record[Natts_pg_auth_members] = {0};
+		bool		new_record_nulls[Natts_pg_auth_members] = {0};
+		bool		new_record_repl[Natts_pg_auth_members] = {0};
 
 		/*
 		 * pg_database_owner is never a role member.  Lifting this restriction
@@ -1500,10 +1493,6 @@ AddRoleMems(const char *rolename, Oid roleid,
 		}
 
 		/* Build a tuple to insert or update */
-		MemSet(new_record, 0, sizeof(new_record));
-		MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-		MemSet(new_record_repl, false, sizeof(new_record_repl));
-
 		new_record[Anum_pg_auth_members_roleid - 1] = ObjectIdGetDatum(roleid);
 		new_record[Anum_pg_auth_members_member - 1] = ObjectIdGetDatum(memberid);
 		new_record[Anum_pg_auth_members_grantor - 1] = ObjectIdGetDatum(grantorId);
@@ -1614,15 +1603,11 @@ DelRoleMems(const char *rolename, Oid roleid,
 		{
 			/* Just turn off the admin option */
 			HeapTuple	tuple;
-			Datum		new_record[Natts_pg_auth_members];
-			bool		new_record_nulls[Natts_pg_auth_members];
-			bool		new_record_repl[Natts_pg_auth_members];
+			Datum		new_record[Natts_pg_auth_members] = {0};
+			bool		new_record_nulls[Natts_pg_auth_members] = {0};
+			bool		new_record_repl[Natts_pg_auth_members] = {0};
 
 			/* Build a tuple to update with */
-			MemSet(new_record, 0, sizeof(new_record));
-			MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-			MemSet(new_record_repl, false, sizeof(new_record_repl));
-
 			new_record[Anum_pg_auth_members_admin_option - 1] = BoolGetDatum(false);
 			new_record_repl[Anum_pg_auth_members_admin_option - 1] = true;
 
diff --git a/src/backend/optimizer/path/costsize.c b/src/backend/optimizer/path/costsize.c
index fcc26b01a4..1e0f1880c5 100644
--- a/src/backend/optimizer/path/costsize.c
+++ b/src/backend/optimizer/path/costsize.c
@@ -2926,13 +2926,12 @@ cost_agg(Path *path, PlannerInfo *root,
 	double		output_tuples;
 	Cost		startup_cost;
 	Cost		total_cost;
-	AggClauseCosts dummy_aggcosts;
+	const AggClauseCosts dummy_aggcosts = {0};
 
 	/* Use all-zero per-aggregate costs if NULL is passed */
 	if (aggcosts == NULL)
 	{
 		Assert(aggstrategy == AGG_HASHED);
-		MemSet(&dummy_aggcosts, 0, sizeof(AggClauseCosts));
 		aggcosts = &dummy_aggcosts;
 	}
 
diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c
index 2a1d44b813..16a0fe59e2 100644
--- a/src/backend/parser/parse_target.c
+++ b/src/backend/parser/parse_target.c
@@ -1594,9 +1594,8 @@ expandRecordVariable(ParseState *pstate, Var *var, int levelsup)
 					 * to.  We have to build an additional level of ParseState
 					 * to keep in step with varlevelsup in the subselect.
 					 */
-					ParseState	mypstate;
+					ParseState	mypstate = {0};
 
-					MemSet(&mypstate, 0, sizeof(mypstate));
 					mypstate.parentParseState = pstate;
 					mypstate.p_rtable = rte->subquery->rtable;
 					/* don't bother filling the rest of the fake pstate */
diff --git a/src/backend/replication/logical/launcher.c b/src/backend/replication/logical/launcher.c
index 2bdab53e19..3bbd522724 100644
--- a/src/backend/replication/logical/launcher.c
+++ b/src/backend/replication/logical/launcher.c
@@ -938,8 +938,8 @@ pg_stat_get_subscription(PG_FUNCTION_ARGS)
 	for (i = 0; i < max_logical_replication_workers; i++)
 	{
 		/* for each row */
-		Datum		values[PG_STAT_GET_SUBSCRIPTION_COLS];
-		bool		nulls[PG_STAT_GET_SUBSCRIPTION_COLS];
+		Datum		values[PG_STAT_GET_SUBSCRIPTION_COLS] = {0};
+		bool		nulls[PG_STAT_GET_SUBSCRIPTION_COLS] = {0};
 		int			worker_pid;
 		LogicalRepWorker worker;
 
@@ -953,9 +953,6 @@ pg_stat_get_subscription(PG_FUNCTION_ARGS)
 
 		worker_pid = worker.proc->pid;
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		values[0] = ObjectIdGetDatum(worker.subid);
 		if (OidIsValid(worker.relid))
 			values[1] = ObjectIdGetDatum(worker.relid);
diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c
index 3c407ab964..3a86786cc3 100644
--- a/src/backend/replication/walsender.c
+++ b/src/backend/replication/walsender.c
@@ -402,7 +402,7 @@ IdentifySystem(void)
 	TupOutputState *tstate;
 	TupleDesc	tupdesc;
 	Datum		values[4];
-	bool		nulls[4];
+	bool		nulls[4] = {0};
 	TimeLineID	currTLI;
 
 	/*
@@ -437,7 +437,6 @@ IdentifySystem(void)
 	}
 
 	dest = CreateDestReceiver(DestRemoteSimple);
-	MemSet(nulls, false, sizeof(nulls));
 
 	/* need a tuple descriptor representing four columns */
 	tupdesc = CreateTemplateTupleDesc(4);
@@ -483,7 +482,7 @@ ReadReplicationSlot(ReadReplicationSlotCmd *cmd)
 	DestReceiver *dest;
 	TupOutputState *tstate;
 	TupleDesc	tupdesc;
-	Datum		values[READ_REPLICATION_SLOT_COLS];
+	Datum		values[READ_REPLICATION_SLOT_COLS] = {0};
 	bool		nulls[READ_REPLICATION_SLOT_COLS];
 
 	tupdesc = CreateTemplateTupleDesc(READ_REPLICATION_SLOT_COLS);
@@ -495,8 +494,7 @@ ReadReplicationSlot(ReadReplicationSlotCmd *cmd)
 	TupleDescInitBuiltinEntry(tupdesc, (AttrNumber) 3, "restart_tli",
 							  INT8OID, -1, 0);
 
-	MemSet(values, 0, READ_REPLICATION_SLOT_COLS * sizeof(Datum));
-	MemSet(nulls, true, READ_REPLICATION_SLOT_COLS * sizeof(bool));
+	memset(nulls, true, READ_REPLICATION_SLOT_COLS * sizeof(bool));
 
 	LWLockAcquire(ReplicationSlotControlLock, LW_SHARED);
 	slot = SearchNamedReplicationSlot(cmd->slotname, false);
@@ -859,13 +857,12 @@ StartReplication(StartReplicationCmd *cmd)
 		TupOutputState *tstate;
 		TupleDesc	tupdesc;
 		Datum		values[2];
-		bool		nulls[2];
+		bool		nulls[2] = {0};
 
 		snprintf(startpos_str, sizeof(startpos_str), "%X/%X",
 				 LSN_FORMAT_ARGS(sendTimeLineValidUpto));
 
 		dest = CreateDestReceiver(DestRemoteSimple);
-		MemSet(nulls, false, sizeof(nulls));
 
 		/*
 		 * Need a tuple descriptor representing two columns. int8 may seem
@@ -1043,7 +1040,7 @@ CreateReplicationSlot(CreateReplicationSlotCmd *cmd)
 	TupOutputState *tstate;
 	TupleDesc	tupdesc;
 	Datum		values[4];
-	bool		nulls[4];
+	bool		nulls[4] = {0};
 
 	Assert(!MyReplicationSlot);
 
@@ -1178,7 +1175,6 @@ CreateReplicationSlot(CreateReplicationSlotCmd *cmd)
 			 LSN_FORMAT_ARGS(MyReplicationSlot->data.confirmed_flush));
 
 	dest = CreateDestReceiver(DestRemoteSimple);
-	MemSet(nulls, false, sizeof(nulls));
 
 	/*----------
 	 * Need a tuple descriptor representing four columns:
@@ -3488,7 +3484,7 @@ pg_stat_get_wal_senders(PG_FUNCTION_ARGS)
 		TimestampTz replyTime;
 		bool		is_sync_standby;
 		Datum		values[PG_STAT_GET_WAL_SENDERS_COLS];
-		bool		nulls[PG_STAT_GET_WAL_SENDERS_COLS];
+		bool		nulls[PG_STAT_GET_WAL_SENDERS_COLS] = {0};
 		int			j;
 
 		/* Collect data from shared memory */
@@ -3527,7 +3523,6 @@ pg_stat_get_wal_senders(PG_FUNCTION_ARGS)
 			}
 		}
 
-		memset(nulls, 0, sizeof(nulls));
 		values[0] = Int32GetDatum(pid);
 
 		if (!has_privs_of_role(GetUserId(), ROLE_PG_READ_ALL_STATS))
diff --git a/src/backend/rewrite/rewriteDefine.c b/src/backend/rewrite/rewriteDefine.c
index 185bf5fbff..a5a1fb887f 100644
--- a/src/backend/rewrite/rewriteDefine.c
+++ b/src/backend/rewrite/rewriteDefine.c
@@ -67,8 +67,7 @@ InsertRule(const char *rulname,
 	char	   *evqual = nodeToString(event_qual);
 	char	   *actiontree = nodeToString((Node *) action);
 	Datum		values[Natts_pg_rewrite];
-	bool		nulls[Natts_pg_rewrite];
-	bool		replaces[Natts_pg_rewrite];
+	bool		nulls[Natts_pg_rewrite] = {0};
 	NameData	rname;
 	Relation	pg_rewrite_desc;
 	HeapTuple	tup,
@@ -81,8 +80,6 @@ InsertRule(const char *rulname,
 	/*
 	 * Set up *nulls and *values arrays
 	 */
-	MemSet(nulls, false, sizeof(nulls));
-
 	namestrcpy(&rname, rulname);
 	values[Anum_pg_rewrite_rulename - 1] = NameGetDatum(&rname);
 	values[Anum_pg_rewrite_ev_class - 1] = ObjectIdGetDatum(eventrel_oid);
@@ -106,6 +103,8 @@ InsertRule(const char *rulname,
 
 	if (HeapTupleIsValid(oldtup))
 	{
+		bool		replaces[Natts_pg_rewrite] = {0};
+
 		if (!replace)
 			ereport(ERROR,
 					(errcode(ERRCODE_DUPLICATE_OBJECT),
@@ -115,7 +114,6 @@ InsertRule(const char *rulname,
 		/*
 		 * When replacing, we don't need to replace every attribute
 		 */
-		MemSet(replaces, false, sizeof(replaces));
 		replaces[Anum_pg_rewrite_ev_type - 1] = true;
 		replaces[Anum_pg_rewrite_is_instead - 1] = true;
 		replaces[Anum_pg_rewrite_ev_qual - 1] = true;
diff --git a/src/backend/utils/adt/acl.c b/src/backend/utils/adt/acl.c
index b7fd3bcf05..6fa58dd8eb 100644
--- a/src/backend/utils/adt/acl.c
+++ b/src/backend/utils/adt/acl.c
@@ -1785,7 +1785,7 @@ aclexplode(PG_FUNCTION_ARGS)
 		{
 			Datum		result;
 			Datum		values[4];
-			bool		nulls[4];
+			bool		nulls[4] = {0};
 			HeapTuple	tuple;
 
 			values[0] = ObjectIdGetDatum(aidata->ai_grantor);
@@ -1793,8 +1793,6 @@ aclexplode(PG_FUNCTION_ARGS)
 			values[2] = CStringGetTextDatum(convert_aclright_to_string(priv_bit));
 			values[3] = BoolGetDatum((ACLITEM_GET_GOPTIONS(*aidata) & priv_bit) != 0);
 
-			MemSet(nulls, 0, sizeof(nulls));
-
 			tuple = heap_form_tuple(funcctx->tuple_desc, values, nulls);
 			result = HeapTupleGetDatum(tuple);
 
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index b0c37ede87..fb167f226a 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -742,11 +742,10 @@ ReadArrayStr(char *arrayStr,
 	bool		eoArray = false;
 	bool		hasnull;
 	int32		totbytes;
-	int			indx[MAXDIM],
+	int			indx[MAXDIM] = {0},
 				prod[MAXDIM];
 
 	mda_get_prod(ndim, dim, prod);
-	MemSet(indx, 0, sizeof(indx));
 
 	/* Initialize is-null markers to true */
 	memset(nulls, true, nitems * sizeof(bool));
diff --git a/src/backend/utils/adt/datetime.c b/src/backend/utils/adt/datetime.c
index 4c12c4d663..43fff50d49 100644
--- a/src/backend/utils/adt/datetime.c
+++ b/src/backend/utils/adt/datetime.c
@@ -4924,7 +4924,7 @@ pg_timezone_abbrevs(PG_FUNCTION_ARGS)
 	Datum		result;
 	HeapTuple	tuple;
 	Datum		values[3];
-	bool		nulls[3];
+	bool		nulls[3] = {0};
 	const datetkn *tp;
 	char		buffer[TOKMAXLEN + 1];
 	int			gmtoffset;
@@ -5011,8 +5011,6 @@ pg_timezone_abbrevs(PG_FUNCTION_ARGS)
 			break;
 	}
 
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/*
 	 * Convert name to text, using upcasing conversion that is the inverse of
 	 * what ParseDateTime() uses.
@@ -5051,7 +5049,7 @@ pg_timezone_names(PG_FUNCTION_ARGS)
 	pg_tzenum  *tzenum;
 	pg_tz	   *tz;
 	Datum		values[4];
-	bool		nulls[4];
+	bool		nulls[4] = {0};
 	int			tzoff;
 	struct pg_tm tm;
 	fsec_t		fsec;
@@ -5088,8 +5086,6 @@ pg_timezone_names(PG_FUNCTION_ARGS)
 		if (tzn && strlen(tzn) > 31)
 			continue;
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		values[0] = CStringGetTextDatum(pg_get_timezone_name(tz));
 		values[1] = CStringGetTextDatum(tzn ? tzn : "");
 
diff --git a/src/backend/utils/adt/lockfuncs.c b/src/backend/utils/adt/lockfuncs.c
index dedee7af5c..f9b324efec 100644
--- a/src/backend/utils/adt/lockfuncs.c
+++ b/src/backend/utils/adt/lockfuncs.c
@@ -172,8 +172,8 @@ pg_lock_status(PG_FUNCTION_ARGS)
 		LOCKMODE	mode = 0;
 		const char *locktypename;
 		char		tnbuf[32];
-		Datum		values[NUM_LOCK_STATUS_COLUMNS];
-		bool		nulls[NUM_LOCK_STATUS_COLUMNS];
+		Datum		values[NUM_LOCK_STATUS_COLUMNS] = {0};
+		bool		nulls[NUM_LOCK_STATUS_COLUMNS] = {0};
 		HeapTuple	tuple;
 		Datum		result;
 		LockInstanceData *instance;
@@ -230,8 +230,6 @@ pg_lock_status(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
 
 		if (instance->locktag.locktag_type <= LOCKTAG_LAST_TYPE)
 			locktypename = LockTagTypeNames[instance->locktag.locktag_type];
@@ -359,8 +357,8 @@ pg_lock_status(PG_FUNCTION_ARGS)
 
 		PREDICATELOCKTARGETTAG *predTag = &(predLockData->locktags[mystatus->predLockIdx]);
 		SERIALIZABLEXACT *xact = &(predLockData->xacts[mystatus->predLockIdx]);
-		Datum		values[NUM_LOCK_STATUS_COLUMNS];
-		bool		nulls[NUM_LOCK_STATUS_COLUMNS];
+		Datum		values[NUM_LOCK_STATUS_COLUMNS] = {0};
+		bool		nulls[NUM_LOCK_STATUS_COLUMNS] = {0};
 		HeapTuple	tuple;
 		Datum		result;
 
@@ -369,8 +367,6 @@ pg_lock_status(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
 
 		/* lock type */
 		lockType = GET_PREDICATELOCKTARGETTAG_TYPE(*predTag);
diff --git a/src/backend/utils/adt/partitionfuncs.c b/src/backend/utils/adt/partitionfuncs.c
index 0243bc061f..109dc8023e 100644
--- a/src/backend/utils/adt/partitionfuncs.c
+++ b/src/backend/utils/adt/partitionfuncs.c
@@ -113,8 +113,8 @@ pg_partition_tree(PG_FUNCTION_ARGS)
 	if (funcctx->call_cntr < list_length(partitions))
 	{
 		Datum		result;
-		Datum		values[PG_PARTITION_TREE_COLS];
-		bool		nulls[PG_PARTITION_TREE_COLS];
+		Datum		values[PG_PARTITION_TREE_COLS] = {0};
+		bool		nulls[PG_PARTITION_TREE_COLS] = {0};
 		HeapTuple	tuple;
 		Oid			parentid = InvalidOid;
 		Oid			relid = list_nth_oid(partitions, funcctx->call_cntr);
@@ -126,8 +126,6 @@ pg_partition_tree(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(nulls, 0, sizeof(nulls));
-		MemSet(values, 0, sizeof(values));
 
 		/* relid */
 		values[0] = ObjectIdGetDatum(relid);
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 893690dad5..d9e2a79382 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -488,13 +488,10 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 	{
 		LocalPgBackendStatus *local_beentry;
 		PgBackendStatus *beentry;
-		Datum		values[PG_STAT_GET_PROGRESS_COLS];
-		bool		nulls[PG_STAT_GET_PROGRESS_COLS];
+		Datum		values[PG_STAT_GET_PROGRESS_COLS] = {0};
+		bool		nulls[PG_STAT_GET_PROGRESS_COLS] = {0};
 		int			i;
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
 
 		if (!local_beentry)
@@ -551,17 +548,14 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 	for (curr_backend = 1; curr_backend <= num_backends; curr_backend++)
 	{
 		/* for each row */
-		Datum		values[PG_STAT_GET_ACTIVITY_COLS];
-		bool		nulls[PG_STAT_GET_ACTIVITY_COLS];
+		Datum		values[PG_STAT_GET_ACTIVITY_COLS] = {0};
+		bool		nulls[PG_STAT_GET_ACTIVITY_COLS] = {0};
 		LocalPgBackendStatus *local_beentry;
 		PgBackendStatus *beentry;
 		PGPROC	   *proc;
 		const char *wait_event_type = NULL;
 		const char *wait_event = NULL;
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		/* Get the next one in the list */
 		local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
 		if (!local_beentry)
@@ -1747,15 +1741,11 @@ pg_stat_get_wal(PG_FUNCTION_ARGS)
 {
 #define PG_STAT_GET_WAL_COLS	9
 	TupleDesc	tupdesc;
-	Datum		values[PG_STAT_GET_WAL_COLS];
-	bool		nulls[PG_STAT_GET_WAL_COLS];
+	Datum		values[PG_STAT_GET_WAL_COLS] = {0};
+	bool		nulls[PG_STAT_GET_WAL_COLS] = {0};
 	char		buf[256];
 	PgStat_WalStats *wal_stats;
 
-	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* Initialise attributes information in the tuple descriptor */
 	tupdesc = CreateTemplateTupleDesc(PG_STAT_GET_WAL_COLS);
 	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "wal_records",
@@ -1826,8 +1816,8 @@ pg_stat_get_slru(PG_FUNCTION_ARGS)
 	for (i = 0;; i++)
 	{
 		/* for each row */
-		Datum		values[PG_STAT_GET_SLRU_COLS];
-		bool		nulls[PG_STAT_GET_SLRU_COLS];
+		Datum		values[PG_STAT_GET_SLRU_COLS] = {0};
+		bool		nulls[PG_STAT_GET_SLRU_COLS] = {0};
 		PgStat_SLRUStats stat;
 		const char *name;
 
@@ -1837,8 +1827,6 @@ pg_stat_get_slru(PG_FUNCTION_ARGS)
 			break;
 
 		stat = stats[i];
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
 
 		values[0] = PointerGetDatum(cstring_to_text(name));
 		values[1] = Int64GetDatum(stat.blocks_zeroed);
@@ -2201,14 +2189,10 @@ Datum
 pg_stat_get_archiver(PG_FUNCTION_ARGS)
 {
 	TupleDesc	tupdesc;
-	Datum		values[7];
-	bool		nulls[7];
+	Datum		values[7] = {0};
+	bool		nulls[7] = {0};
 	PgStat_ArchiverStats *archiver_stats;
 
-	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* Initialise attributes information in the tuple descriptor */
 	tupdesc = CreateTemplateTupleDesc(7);
 	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "archived_count",
@@ -2274,15 +2258,11 @@ pg_stat_get_replication_slot(PG_FUNCTION_ARGS)
 	text	   *slotname_text = PG_GETARG_TEXT_P(0);
 	NameData	slotname;
 	TupleDesc	tupdesc;
-	Datum		values[PG_STAT_GET_REPLICATION_SLOT_COLS];
-	bool		nulls[PG_STAT_GET_REPLICATION_SLOT_COLS];
+	Datum		values[PG_STAT_GET_REPLICATION_SLOT_COLS] = {0};
+	bool		nulls[PG_STAT_GET_REPLICATION_SLOT_COLS] = {0};
 	PgStat_StatReplSlotEntry *slotent;
 	PgStat_StatReplSlotEntry allzero;
 
-	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* Initialise attributes information in the tuple descriptor */
 	tupdesc = CreateTemplateTupleDesc(PG_STAT_GET_REPLICATION_SLOT_COLS);
 	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "slot_name",
@@ -2348,8 +2328,8 @@ pg_stat_get_subscription_stats(PG_FUNCTION_ARGS)
 #define PG_STAT_GET_SUBSCRIPTION_STATS_COLS	4
 	Oid			subid = PG_GETARG_OID(0);
 	TupleDesc	tupdesc;
-	Datum		values[PG_STAT_GET_SUBSCRIPTION_STATS_COLS];
-	bool		nulls[PG_STAT_GET_SUBSCRIPTION_STATS_COLS];
+	Datum		values[PG_STAT_GET_SUBSCRIPTION_STATS_COLS] = {0};
+	bool		nulls[PG_STAT_GET_SUBSCRIPTION_STATS_COLS] = {0};
 	PgStat_StatSubEntry *subentry;
 	PgStat_StatSubEntry allzero;
 
@@ -2368,10 +2348,6 @@ pg_stat_get_subscription_stats(PG_FUNCTION_ARGS)
 					   TIMESTAMPTZOID, -1, 0);
 	BlessTupleDesc(tupdesc);
 
-	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	if (!subentry)
 	{
 		/* If the subscription is not found, initialise its stats */
diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c
index fa1f589fad..6f99b5b243 100644
--- a/src/backend/utils/adt/selfuncs.c
+++ b/src/backend/utils/adt/selfuncs.c
@@ -6642,10 +6642,10 @@ btcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 			   double *indexPages)
 {
 	IndexOptInfo *index = path->indexinfo;
-	GenericCosts costs;
+	GenericCosts costs = {0};
 	Oid			relid;
 	AttrNumber	colnum;
-	VariableStatData vardata;
+	VariableStatData vardata = {0};
 	double		numIndexTuples;
 	Cost		descentCost;
 	List	   *indexBoundQuals;
@@ -6797,7 +6797,6 @@ btcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	/*
 	 * Now do generic index cost estimation.
 	 */
-	MemSet(&costs, 0, sizeof(costs));
 	costs.numIndexTuples = numIndexTuples;
 
 	genericcostestimate(root, path, loop_count, &costs);
@@ -6842,8 +6841,6 @@ btcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	 * ordering, but don't negate it entirely.  Before 8.0 we divided the
 	 * correlation by the number of columns, but that seems too strong.)
 	 */
-	MemSet(&vardata, 0, sizeof(vardata));
-
 	if (index->indexkeys[0] != 0)
 	{
 		/* Simple variable --- look to stats for the underlying table */
@@ -6947,9 +6944,7 @@ hashcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 				 Selectivity *indexSelectivity, double *indexCorrelation,
 				 double *indexPages)
 {
-	GenericCosts costs;
-
-	MemSet(&costs, 0, sizeof(costs));
+	GenericCosts costs = {0};
 
 	genericcostestimate(root, path, loop_count, &costs);
 
@@ -6992,11 +6987,9 @@ gistcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 				 double *indexPages)
 {
 	IndexOptInfo *index = path->indexinfo;
-	GenericCosts costs;
+	GenericCosts costs = {0};
 	Cost		descentCost;
 
-	MemSet(&costs, 0, sizeof(costs));
-
 	genericcostestimate(root, path, loop_count, &costs);
 
 	/*
@@ -7049,11 +7042,9 @@ spgcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 				double *indexPages)
 {
 	IndexOptInfo *index = path->indexinfo;
-	GenericCosts costs;
+	GenericCosts costs = {0};
 	Cost		descentCost;
 
-	MemSet(&costs, 0, sizeof(costs));
-
 	genericcostestimate(root, path, loop_count, &costs);
 
 	/*
diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index f70f829d83..49cdb290ac 100644
--- a/src/backend/utils/adt/timestamp.c
+++ b/src/backend/utils/adt/timestamp.c
@@ -2403,7 +2403,7 @@ interval_cmp_value(const Interval *interval)
 }
 
 static int
-interval_cmp_internal(Interval *interval1, Interval *interval2)
+interval_cmp_internal(const Interval *interval1, const Interval *interval2)
 {
 	INT128		span1 = interval_cmp_value(interval1);
 	INT128		span2 = interval_cmp_value(interval2);
@@ -5777,7 +5777,7 @@ generate_series_timestamp(PG_FUNCTION_ARGS)
 		Timestamp	finish = PG_GETARG_TIMESTAMP(1);
 		Interval   *step = PG_GETARG_INTERVAL_P(2);
 		MemoryContext oldcontext;
-		Interval	interval_zero;
+		const Interval interval_zero = {0};
 
 		/* create a function context for cross-call persistence */
 		funcctx = SRF_FIRSTCALL_INIT();
@@ -5800,7 +5800,6 @@ generate_series_timestamp(PG_FUNCTION_ARGS)
 		fctx->step = *step;
 
 		/* Determine sign of the interval */
-		MemSet(&interval_zero, 0, sizeof(Interval));
 		fctx->step_sign = interval_cmp_internal(&fctx->step, &interval_zero);
 
 		if (fctx->step_sign == 0)
@@ -5857,7 +5856,7 @@ generate_series_timestamptz(PG_FUNCTION_ARGS)
 		TimestampTz finish = PG_GETARG_TIMESTAMPTZ(1);
 		Interval   *step = PG_GETARG_INTERVAL_P(2);
 		MemoryContext oldcontext;
-		Interval	interval_zero;
+		const Interval interval_zero = {0};
 
 		/* create a function context for cross-call persistence */
 		funcctx = SRF_FIRSTCALL_INIT();
@@ -5880,7 +5879,6 @@ generate_series_timestamptz(PG_FUNCTION_ARGS)
 		fctx->step = *step;
 
 		/* Determine sign of the interval */
-		MemSet(&interval_zero, 0, sizeof(Interval));
 		fctx->step_sign = interval_cmp_internal(&fctx->step, &interval_zero);
 
 		if (fctx->step_sign == 0)
diff --git a/src/backend/utils/mmgr/portalmem.c b/src/backend/utils/mmgr/portalmem.c
index d549f66d4a..3a161bdb88 100644
--- a/src/backend/utils/mmgr/portalmem.c
+++ b/src/backend/utils/mmgr/portalmem.c
@@ -1146,14 +1146,12 @@ pg_cursor(PG_FUNCTION_ARGS)
 	{
 		Portal		portal = hentry->portal;
 		Datum		values[6];
-		bool		nulls[6];
+		bool		nulls[6] = {0};
 
 		/* report only "visible" entries */
 		if (!portal->visible)
 			continue;
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		values[0] = CStringGetTextDatum(portal->name);
 		values[1] = CStringGetTextDatum(portal->sourceText);
 		values[2] = BoolGetDatum(portal->cursorOptions & CURSOR_OPT_HOLD);
diff --git a/src/bin/pg_basebackup/pg_basebackup.c b/src/bin/pg_basebackup/pg_basebackup.c
index 4445a86aee..79b23fa7d7 100644
--- a/src/bin/pg_basebackup/pg_basebackup.c
+++ b/src/bin/pg_basebackup/pg_basebackup.c
@@ -447,7 +447,7 @@ reached_end_position(XLogRecPtr segendpos, uint32 timeline,
 	{
 #ifndef WIN32
 		fd_set		fds;
-		struct timeval tv;
+		struct timeval tv = {0};
 		int			r;
 
 		/*
@@ -457,16 +457,13 @@ reached_end_position(XLogRecPtr segendpos, uint32 timeline,
 		FD_ZERO(&fds);
 		FD_SET(bgpipe[0], &fds);
 
-		MemSet(&tv, 0, sizeof(tv));
-
 		r = select(bgpipe[0] + 1, &fds, NULL, NULL, &tv);
 		if (r == 1)
 		{
-			char		xlogend[64];
+			char		xlogend[64] = {0};
 			uint32		hi,
 						lo;
 
-			MemSet(xlogend, 0, sizeof(xlogend));
 			r = read(bgpipe[0], xlogend, sizeof(xlogend) - 1);
 			if (r < 0)
 				pg_fatal("could not read from ready pipe: %m");
@@ -528,11 +525,10 @@ typedef struct
 static int
 LogStreamerMain(logstreamer_param *param)
 {
-	StreamCtl	stream;
+	StreamCtl	stream = {0};
 
 	in_log_streamer = true;
 
-	MemSet(&stream, 0, sizeof(stream));
 	stream.startpos = param->startptr;
 	stream.timeline = param->timeline;
 	stream.sysidentifier = param->sysidentifier;
@@ -1952,7 +1948,6 @@ BaseBackup(char *compression_algorithm, char *compression_detail,
 	else
 		starttli = latesttli;
 	PQclear(res);
-	MemSet(xlogend, 0, sizeof(xlogend));
 
 	if (verbose && includewal != NO_WAL)
 		pg_log_info("write-ahead log start point: %s on timeline %u",
diff --git a/src/bin/pg_basebackup/pg_receivewal.c b/src/bin/pg_basebackup/pg_receivewal.c
index ea3902c971..f064cff4ab 100644
--- a/src/bin/pg_basebackup/pg_receivewal.c
+++ b/src/bin/pg_basebackup/pg_receivewal.c
@@ -564,11 +564,9 @@ StreamLog(void)
 {
 	XLogRecPtr	serverpos;
 	TimeLineID	servertli;
-	StreamCtl	stream;
+	StreamCtl	stream = {0};
 	char	   *sysidentifier;
 
-	MemSet(&stream, 0, sizeof(stream));
-
 	/*
 	 * Connect in replication mode to the server
 	 */
diff --git a/src/bin/pg_basebackup/walmethods.c b/src/bin/pg_basebackup/walmethods.c
index ef4c11277a..e90aa0ba37 100644
--- a/src/bin/pg_basebackup/walmethods.c
+++ b/src/bin/pg_basebackup/walmethods.c
@@ -1111,9 +1111,8 @@ tar_close(Walfile f, WalCloseMethod method)
 	padding = tarPaddingBytesRequired(filesize);
 	if (padding)
 	{
-		char		zerobuf[TAR_BLOCK_SIZE];
+		char		zerobuf[TAR_BLOCK_SIZE] = {0};
 
-		MemSet(zerobuf, 0, padding);
 		if (tar_write(f, zerobuf, padding) != padding)
 			return -1;
 	}
@@ -1222,7 +1221,7 @@ tar_existsfile(const char *pathname)
 static bool
 tar_finish(void)
 {
-	char		zerobuf[1024];
+	char		zerobuf[1024] = {0};
 
 	tar_clear_error();
 
@@ -1233,7 +1232,6 @@ tar_finish(void)
 	}
 
 	/* A tarfile always ends with two empty blocks */
-	MemSet(zerobuf, 0, sizeof(zerobuf));
 	if (tar_data->compression_algorithm == PG_COMPRESSION_NONE)
 	{
 		errno = 0;
diff --git a/src/common/ip.c b/src/common/ip.c
index cd73d49679..267103efb9 100644
--- a/src/common/ip.c
+++ b/src/common/ip.c
@@ -165,14 +165,12 @@ static int
 getaddrinfo_unix(const char *path, const struct addrinfo *hintsp,
 				 struct addrinfo **result)
 {
-	struct addrinfo hints;
+	struct addrinfo hints = {0};
 	struct addrinfo *aip;
 	struct sockaddr_un *unp;
 
 	*result = NULL;
 
-	MemSet(&hints, 0, sizeof(hints));
-
 	if (strlen(path) >= sizeof(unp->sun_path))
 		return EAI_FAIL;
 
diff --git a/src/port/snprintf.c b/src/port/snprintf.c
index abb1c59770..e646b0e642 100644
--- a/src/port/snprintf.c
+++ b/src/port/snprintf.c
@@ -756,12 +756,9 @@ find_arguments(const char *format, va_list args,
 	int			longflag;
 	int			fmtpos;
 	int			i;
-	int			last_dollar;
-	PrintfArgType argtypes[PG_NL_ARGMAX + 1];
-
 	/* Initialize to "no dollar arguments known" */
-	last_dollar = 0;
-	MemSet(argtypes, 0, sizeof(argtypes));
+	int			last_dollar = 0;
+	PrintfArgType argtypes[PG_NL_ARGMAX + 1] = {0};
 
 	/*
 	 * This loop must accept the same format strings as the one in dopr().
diff --git a/src/test/modules/test_predtest/test_predtest.c b/src/test/modules/test_predtest/test_predtest.c
index 3b19e0eadc..2ce88cb624 100644
--- a/src/test/modules/test_predtest/test_predtest.c
+++ b/src/test/modules/test_predtest/test_predtest.c
@@ -50,7 +50,7 @@ test_predtest(PG_FUNCTION_ARGS)
 				strong_refuted_by,
 				weak_refuted_by;
 	Datum		values[8];
-	bool		nulls[8];
+	bool		nulls[8] = {0};
 	int			i;
 
 	/* We use SPI to parse, plan, and execute the test query */
@@ -204,7 +204,6 @@ test_predtest(PG_FUNCTION_ARGS)
 					   "w_r_holds", BOOLOID, -1, 0);
 	tupdesc = BlessTupleDesc(tupdesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = BoolGetDatum(strong_implied_by);
 	values[1] = BoolGetDatum(weak_implied_by);
 	values[2] = BoolGetDatum(strong_refuted_by);
diff --git a/src/test/regress/regress.c b/src/test/regress/regress.c
index ba3532a51e..b88d70b6fc 100644
--- a/src/test/regress/regress.c
+++ b/src/test/regress/regress.c
@@ -1110,7 +1110,7 @@ test_enc_conversion(PG_FUNCTION_ARGS)
 	int			convertedbytes;
 	int			dstlen;
 	Datum		values[2];
-	bool		nulls[2];
+	bool		nulls[2] = {0};
 	HeapTuple	tuple;
 
 	if (src_encoding < 0)
@@ -1199,7 +1199,6 @@ test_enc_conversion(PG_FUNCTION_ARGS)
 		pfree(dst);
 	}
 
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = Int32GetDatum(convertedbytes);
 	values[1] = PointerGetDatum(retval);
 	tuple = heap_form_tuple(tupdesc, values, nulls);
-- 
2.36.1

diff --git a/contrib/amcheck/verify_heapam.c b/contrib/amcheck/verify_heapam.c
index e488f5e234..4cd4354278 100644
--- a/contrib/amcheck/verify_heapam.c
+++ b/contrib/amcheck/verify_heapam.c
@@ -554,17 +554,15 @@ report_corruption_internal(Tuplestorestate *tupstore, TupleDesc tupdesc,
 						   BlockNumber blkno, OffsetNumber offnum,
 						   AttrNumber attnum, char *msg)
 {
-	Datum		values[HEAPCHECK_RELATION_COLS];
-	bool		nulls[HEAPCHECK_RELATION_COLS];
+	Datum		values[HEAPCHECK_RELATION_COLS] = {0};
+	bool		nulls[HEAPCHECK_RELATION_COLS] = {0};
 	HeapTuple	tuple;
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = Int64GetDatum(blkno);
 	values[1] = Int32GetDatum(offnum);
 	values[2] = Int32GetDatum(attnum);
-	nulls[2] = (attnum < 0);
 	values[3] = CStringGetTextDatum(msg);
+	nulls[2] = (attnum < 0);
 
 	/*
 	 * In principle, there is nothing to prevent a scan over a large, highly
diff --git a/contrib/bloom/blcost.c b/contrib/bloom/blcost.c
index d42e4e9628..d4b1c76303 100644
--- a/contrib/bloom/blcost.c
+++ b/contrib/bloom/blcost.c
@@ -26,9 +26,7 @@ blcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 			   double *indexPages)
 {
 	IndexOptInfo *index = path->indexinfo;
-	GenericCosts costs;
-
-	MemSet(&costs, 0, sizeof(costs));
+	GenericCosts costs = {0};
 
 	/* We have to visit all index tuples anyway */
 	costs.numIndexTuples = index->tuples;
diff --git a/contrib/pageinspect/brinfuncs.c b/contrib/pageinspect/brinfuncs.c
index 879276e6de..f4c959ecab 100644
--- a/contrib/pageinspect/brinfuncs.c
+++ b/contrib/pageinspect/brinfuncs.c
@@ -202,7 +202,7 @@ brin_page_items(PG_FUNCTION_ARGS)
 	for (;;)
 	{
 		Datum		values[7];
-		bool		nulls[7];
+		bool		nulls[7] = {0};
 
 		/*
 		 * This loop is called once for every attribute of every tuple in the
@@ -230,8 +230,6 @@ brin_page_items(PG_FUNCTION_ARGS)
 		else
 			attno++;
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		if (unusedItem)
 		{
 			values[0] = UInt16GetDatum(offset);
@@ -334,7 +332,7 @@ brin_metapage_info(PG_FUNCTION_ARGS)
 	BrinMetaPageData *meta;
 	TupleDesc	tupdesc;
 	Datum		values[4];
-	bool		nulls[4];
+	bool		nulls[4] = {0};
 	HeapTuple	htup;
 
 	if (!superuser())
@@ -354,7 +352,6 @@ brin_metapage_info(PG_FUNCTION_ARGS)
 
 	/* Extract values from the metapage */
 	meta = (BrinMetaPageData *) PageGetContents(page);
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = CStringGetTextDatum(psprintf("0x%08X", meta->brinMagic));
 	values[1] = Int32GetDatum(meta->brinVersion);
 	values[2] = Int32GetDatum(meta->pagesPerRange);
diff --git a/contrib/pageinspect/hashfuncs.c b/contrib/pageinspect/hashfuncs.c
index 5287dbe1a3..81815392d7 100644
--- a/contrib/pageinspect/hashfuncs.c
+++ b/contrib/pageinspect/hashfuncs.c
@@ -238,7 +238,7 @@ hash_page_stats(PG_FUNCTION_ARGS)
 	Page		page;
 	int			j;
 	Datum		values[9];
-	bool		nulls[9];
+	bool		nulls[9] = {0};
 	HashPageStat stat;
 	HeapTuple	tuple;
 	TupleDesc	tupleDesc;
@@ -261,8 +261,6 @@ hash_page_stats(PG_FUNCTION_ARGS)
 		elog(ERROR, "return type must be a row type");
 	tupleDesc = BlessTupleDesc(tupleDesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
-
 	j = 0;
 	values[j++] = Int32GetDatum(stat.live_items);
 	values[j++] = Int32GetDatum(stat.dead_items);
@@ -303,7 +301,7 @@ hash_page_items(PG_FUNCTION_ARGS)
 	Page		page;
 	Datum		result;
 	Datum		values[3];
-	bool		nulls[3];
+	bool		nulls[3] = {0};
 	uint32		hashkey;
 	HeapTuple	tuple;
 	FuncCallContext *fctx;
@@ -361,8 +359,6 @@ hash_page_items(PG_FUNCTION_ARGS)
 
 		itup = (IndexTuple) PageGetItem(uargs->page, id);
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		j = 0;
 		values[j++] = Int32GetDatum((int32) uargs->offset);
 		values[j++] = PointerGetDatum(&itup->t_tid);
@@ -409,7 +405,7 @@ hash_bitmap_info(PG_FUNCTION_ARGS)
 	int			i,
 				j;
 	Datum		values[3];
-	bool		nulls[3];
+	bool		nulls[3] = {0};
 	uint32	   *freep;
 
 	if (!superuser())
@@ -495,8 +491,6 @@ hash_bitmap_info(PG_FUNCTION_ARGS)
 		elog(ERROR, "return type must be a row type");
 	tupleDesc = BlessTupleDesc(tupleDesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
-
 	j = 0;
 	values[j++] = Int64GetDatum((int64) bitmapblkno);
 	values[j++] = Int32GetDatum(bitmapbit);
@@ -526,7 +520,7 @@ hash_metapage_info(PG_FUNCTION_ARGS)
 	int			i,
 				j;
 	Datum		values[16];
-	bool		nulls[16];
+	bool		nulls[16] = {0};
 	Datum		spares[HASH_MAX_SPLITPOINTS];
 	Datum		mapp[HASH_MAX_BITMAPS];
 
@@ -544,8 +538,6 @@ hash_metapage_info(PG_FUNCTION_ARGS)
 
 	metad = HashPageGetMeta(page);
 
-	MemSet(nulls, 0, sizeof(nulls));
-
 	j = 0;
 	values[j++] = Int64GetDatum((int64) metad->hashm_magic);
 	values[j++] = Int64GetDatum((int64) metad->hashm_version);
diff --git a/contrib/pageinspect/heapfuncs.c b/contrib/pageinspect/heapfuncs.c
index a654234c6b..952f5ed57e 100644
--- a/contrib/pageinspect/heapfuncs.c
+++ b/contrib/pageinspect/heapfuncs.c
@@ -181,13 +181,11 @@ heap_page_items(PG_FUNCTION_ARGS)
 		Datum		result;
 		ItemId		id;
 		Datum		values[14];
-		bool		nulls[14];
+		bool		nulls[14] = {0};
 		uint16		lp_offset;
 		uint16		lp_flags;
 		uint16		lp_len;
 
-		memset(nulls, 0, sizeof(nulls));
-
 		/* Extract information from the line pointer */
 
 		id = PageGetItemId(page, inter_call_data->offset);
@@ -507,8 +505,8 @@ Datum
 heap_tuple_infomask_flags(PG_FUNCTION_ARGS)
 {
 #define HEAP_TUPLE_INFOMASK_COLS 2
-	Datum		values[HEAP_TUPLE_INFOMASK_COLS];
-	bool		nulls[HEAP_TUPLE_INFOMASK_COLS];
+	Datum		values[HEAP_TUPLE_INFOMASK_COLS] = {0};
+	bool		nulls[HEAP_TUPLE_INFOMASK_COLS] = {0};
 	uint16		t_infomask = PG_GETARG_INT16(0);
 	uint16		t_infomask2 = PG_GETARG_INT16(1);
 	int			cnt = 0;
@@ -530,10 +528,6 @@ heap_tuple_infomask_flags(PG_FUNCTION_ARGS)
 	bitcnt = pg_popcount((const char *) &t_infomask, sizeof(uint16)) +
 		pg_popcount((const char *) &t_infomask2, sizeof(uint16));
 
-	/* Initialize values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* If no flags, return a set of empty arrays */
 	if (bitcnt <= 0)
 	{
diff --git a/contrib/pg_prewarm/autoprewarm.c b/contrib/pg_prewarm/autoprewarm.c
index 13eee4a137..ee20e9b085 100644
--- a/contrib/pg_prewarm/autoprewarm.c
+++ b/contrib/pg_prewarm/autoprewarm.c
@@ -814,12 +814,11 @@ apw_detach_shmem(int code, Datum arg)
 static void
 apw_start_leader_worker(void)
 {
-	BackgroundWorker worker;
+	BackgroundWorker worker = {0};
 	BackgroundWorkerHandle *handle;
 	BgwHandleStatus status;
 	pid_t		pid;
 
-	MemSet(&worker, 0, sizeof(BackgroundWorker));
 	worker.bgw_flags = BGWORKER_SHMEM_ACCESS;
 	worker.bgw_start_time = BgWorkerStart_ConsistentState;
 	strcpy(worker.bgw_library_name, "pg_prewarm");
@@ -856,10 +855,9 @@ apw_start_leader_worker(void)
 static void
 apw_start_database_worker(void)
 {
-	BackgroundWorker worker;
+	BackgroundWorker worker = {0};
 	BackgroundWorkerHandle *handle;
 
-	MemSet(&worker, 0, sizeof(BackgroundWorker));
 	worker.bgw_flags =
 		BGWORKER_SHMEM_ACCESS | BGWORKER_BACKEND_DATABASE_CONNECTION;
 	worker.bgw_start_time = BgWorkerStart_ConsistentState;
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index 4acfddcdb8..b4d4231dc6 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -1854,8 +1854,8 @@ pg_stat_statements_info(PG_FUNCTION_ARGS)
 {
 	pgssGlobalStats stats;
 	TupleDesc	tupdesc;
-	Datum		values[PG_STAT_STATEMENTS_INFO_COLS];
-	bool		nulls[PG_STAT_STATEMENTS_INFO_COLS];
+	Datum		values[PG_STAT_STATEMENTS_INFO_COLS] = {0};
+	bool		nulls[PG_STAT_STATEMENTS_INFO_COLS] = {0};
 
 	if (!pgss || !pgss_hash)
 		ereport(ERROR,
@@ -1866,9 +1866,6 @@ pg_stat_statements_info(PG_FUNCTION_ARGS)
 	if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
 		elog(ERROR, "return type must be a row type");
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* Read global statistics for pg_stat_statements */
 	{
 		volatile pgssSharedState *s = (volatile pgssSharedState *) pgss;
diff --git a/contrib/pg_trgm/trgm_regexp.c b/contrib/pg_trgm/trgm_regexp.c
index 58d32ba946..a155d4c13d 100644
--- a/contrib/pg_trgm/trgm_regexp.c
+++ b/contrib/pg_trgm/trgm_regexp.c
@@ -905,7 +905,7 @@ static void
 transformGraph(TrgmNFA *trgmNFA)
 {
 	HASHCTL		hashCtl;
-	TrgmStateKey initkey;
+	TrgmStateKey initkey = {0};
 	TrgmState  *initstate;
 	ListCell   *lc;
 
@@ -926,7 +926,6 @@ transformGraph(TrgmNFA *trgmNFA)
 	trgmNFA->nstates = 0;
 
 	/* Create initial state: ambiguous prefix, NFA's initial state */
-	MemSet(&initkey, 0, sizeof(initkey));
 	initkey.prefix.colors[0] = COLOR_UNKNOWN;
 	initkey.prefix.colors[1] = COLOR_UNKNOWN;
 	initkey.nstate = pg_reg_getinitialstate(trgmNFA->regex);
@@ -1014,22 +1013,19 @@ processState(TrgmNFA *trgmNFA, TrgmState *state)
  *
  * Note that we don't generate any actual arcs here.  addArcs will do that
  * later, after we have identified all the enter keys for this state.
+ *
+ * Ensure any pad bytes in destKey are zero, since it may get used as a
+ * hashtable key by getState.
  */
 static void
 addKey(TrgmNFA *trgmNFA, TrgmState *state, TrgmStateKey *key)
 {
 	regex_arc_t *arcs;
-	TrgmStateKey destKey;
+	TrgmStateKey destKey = {0};
 	ListCell   *cell;
 	int			i,
 				arcsCount;
 
-	/*
-	 * Ensure any pad bytes in destKey are zero, since it may get used as a
-	 * hashtable key by getState.
-	 */
-	MemSet(&destKey, 0, sizeof(destKey));
-
 	/*
 	 * Compare key to each existing enter key of the state to check for
 	 * redundancy.  We can drop either old key(s) or the new key if we find
@@ -1195,22 +1191,19 @@ addKeyToQueue(TrgmNFA *trgmNFA, TrgmStateKey *key)
 
 /*
  * Add outgoing arcs from given state, whose enter keys are all now known.
+ *
+ * Ensure any pad bytes in destKey are zero, since it may get used as a
+ * hashtable key by getState.
  */
 static void
 addArcs(TrgmNFA *trgmNFA, TrgmState *state)
 {
-	TrgmStateKey destKey;
+	TrgmStateKey destKey = {0};
 	ListCell   *cell;
 	regex_arc_t *arcs;
 	int			arcsCount,
 				i;
 
-	/*
-	 * Ensure any pad bytes in destKey are zero, since it may get used as a
-	 * hashtable key by getState.
-	 */
-	MemSet(&destKey, 0, sizeof(destKey));
-
 	/*
 	 * Iterate over enter keys associated with this expanded-graph state. This
 	 * includes both the state's own stateKey, and any enter keys we added to
diff --git a/contrib/pg_visibility/pg_visibility.c b/contrib/pg_visibility/pg_visibility.c
index 4e2e9ea9bb..a95f73ec79 100644
--- a/contrib/pg_visibility/pg_visibility.c
+++ b/contrib/pg_visibility/pg_visibility.c
@@ -75,7 +75,7 @@ pg_visibility_map(PG_FUNCTION_ARGS)
 	Buffer		vmbuffer = InvalidBuffer;
 	TupleDesc	tupdesc;
 	Datum		values[2];
-	bool		nulls[2];
+	bool		nulls[2] = {0};
 
 	rel = relation_open(relid, AccessShareLock);
 
@@ -88,7 +88,6 @@ pg_visibility_map(PG_FUNCTION_ARGS)
 				 errmsg("invalid block number")));
 
 	tupdesc = pg_visibility_tupdesc(false, false);
-	MemSet(nulls, 0, sizeof(nulls));
 
 	mapbits = (int32) visibilitymap_get_status(rel, blkno, &vmbuffer);
 	if (vmbuffer != InvalidBuffer)
@@ -117,7 +116,7 @@ pg_visibility(PG_FUNCTION_ARGS)
 	Page		page;
 	TupleDesc	tupdesc;
 	Datum		values[3];
-	bool		nulls[3];
+	bool		nulls[3] = {0};
 
 	rel = relation_open(relid, AccessShareLock);
 
@@ -130,7 +129,6 @@ pg_visibility(PG_FUNCTION_ARGS)
 				 errmsg("invalid block number")));
 
 	tupdesc = pg_visibility_tupdesc(false, true);
-	MemSet(nulls, 0, sizeof(nulls));
 
 	mapbits = (int32) visibilitymap_get_status(rel, blkno, &vmbuffer);
 	if (vmbuffer != InvalidBuffer)
@@ -188,10 +186,9 @@ pg_visibility_map_rel(PG_FUNCTION_ARGS)
 	if (info->next < info->count)
 	{
 		Datum		values[3];
-		bool		nulls[3];
+		bool		nulls[3] = {0};
 		HeapTuple	tuple;
 
-		MemSet(nulls, 0, sizeof(nulls));
 		values[0] = Int64GetDatum(info->next);
 		values[1] = BoolGetDatum((info->bits[info->next] & (1 << 0)) != 0);
 		values[2] = BoolGetDatum((info->bits[info->next] & (1 << 1)) != 0);
@@ -233,10 +230,9 @@ pg_visibility_rel(PG_FUNCTION_ARGS)
 	if (info->next < info->count)
 	{
 		Datum		values[4];
-		bool		nulls[4];
+		bool		nulls[4] = {0};
 		HeapTuple	tuple;
 
-		MemSet(nulls, 0, sizeof(nulls));
 		values[0] = Int64GetDatum(info->next);
 		values[1] = BoolGetDatum((info->bits[info->next] & (1 << 0)) != 0);
 		values[2] = BoolGetDatum((info->bits[info->next] & (1 << 1)) != 0);
@@ -266,7 +262,7 @@ pg_visibility_map_summary(PG_FUNCTION_ARGS)
 	int64		all_frozen = 0;
 	TupleDesc	tupdesc;
 	Datum		values[2];
-	bool		nulls[2];
+	bool		nulls[2] = {0};
 
 	rel = relation_open(relid, AccessShareLock);
 
@@ -300,7 +296,6 @@ pg_visibility_map_summary(PG_FUNCTION_ARGS)
 	TupleDescInitEntry(tupdesc, (AttrNumber) 2, "all_frozen", INT8OID, -1, 0);
 	tupdesc = BlessTupleDesc(tupdesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = Int64GetDatum(all_visible);
 	values[1] = Int64GetDatum(all_frozen);
 
diff --git a/contrib/pg_walinspect/pg_walinspect.c b/contrib/pg_walinspect/pg_walinspect.c
index a082dfb331..9081787634 100644
--- a/contrib/pg_walinspect/pg_walinspect.c
+++ b/contrib/pg_walinspect/pg_walinspect.c
@@ -229,8 +229,8 @@ pg_get_wal_record_info(PG_FUNCTION_ARGS)
 {
 #define PG_GET_WAL_RECORD_INFO_COLS 11
 	Datum		result;
-	Datum		values[PG_GET_WAL_RECORD_INFO_COLS];
-	bool		nulls[PG_GET_WAL_RECORD_INFO_COLS];
+	Datum		values[PG_GET_WAL_RECORD_INFO_COLS] = {0};
+	bool		nulls[PG_GET_WAL_RECORD_INFO_COLS] = {0};
 	XLogRecPtr	lsn;
 	XLogRecPtr	curr_lsn;
 	XLogRecPtr	first_record;
@@ -266,9 +266,6 @@ pg_get_wal_record_info(PG_FUNCTION_ARGS)
 				 errmsg("could not read WAL at %X/%X",
 						LSN_FORMAT_ARGS(first_record))));
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	GetWALRecordInfo(xlogreader, first_record, values, nulls,
 					 PG_GET_WAL_RECORD_INFO_COLS);
 
@@ -334,8 +331,8 @@ GetWALRecordsInfo(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
 	XLogRecPtr	first_record;
 	XLogReaderState *xlogreader;
 	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
-	Datum		values[PG_GET_WAL_RECORDS_INFO_COLS];
-	bool		nulls[PG_GET_WAL_RECORDS_INFO_COLS];
+	Datum		values[PG_GET_WAL_RECORDS_INFO_COLS] = {0};
+	bool		nulls[PG_GET_WAL_RECORDS_INFO_COLS] = {0};
 
 	SetSingleFuncCall(fcinfo, 0);
 
@@ -343,9 +340,6 @@ GetWALRecordsInfo(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
 
 	Assert(xlogreader);
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	while (ReadNextXLogRecord(xlogreader, first_record) &&
 		   xlogreader->EndRecPtr <= end_lsn)
 	{
@@ -556,17 +550,15 @@ GetWalStats(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
 #define PG_GET_WAL_STATS_COLS 9
 	XLogRecPtr	first_record;
 	XLogReaderState *xlogreader;
-	XLogStats	stats;
+	XLogStats	stats = {0};
 	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
-	Datum		values[PG_GET_WAL_STATS_COLS];
-	bool		nulls[PG_GET_WAL_STATS_COLS];
+	Datum		values[PG_GET_WAL_STATS_COLS] = {0};
+	bool		nulls[PG_GET_WAL_STATS_COLS] = {0};
 
 	SetSingleFuncCall(fcinfo, 0);
 
 	xlogreader = InitXLogReaderState(start_lsn, &first_record);
 
-	MemSet(&stats, 0, sizeof(stats));
-
 	while (ReadNextXLogRecord(xlogreader, first_record) &&
 		   xlogreader->EndRecPtr <= end_lsn)
 	{
@@ -578,9 +570,6 @@ GetWalStats(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
 	pfree(xlogreader->private_data);
 	XLogReaderFree(xlogreader);
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	GetXLogSummaryStats(&stats, rsinfo, values, nulls,
 						PG_GET_WAL_STATS_COLS,
 						stats_per_record);
diff --git a/contrib/pgstattuple/pgstatindex.c b/contrib/pgstattuple/pgstatindex.c
index e1048e47ff..d69ac1c93d 100644
--- a/contrib/pgstattuple/pgstatindex.c
+++ b/contrib/pgstattuple/pgstatindex.c
@@ -575,7 +575,7 @@ pgstathashindex(PG_FUNCTION_ARGS)
 	HeapTuple	tuple;
 	TupleDesc	tupleDesc;
 	Datum		values[8];
-	bool		nulls[8];
+	bool		nulls[8] = {0};
 	Buffer		metabuf;
 	HashMetaPage metap;
 	float8		free_percent;
@@ -697,7 +697,6 @@ pgstathashindex(PG_FUNCTION_ARGS)
 	/*
 	 * Build and return the tuple
 	 */
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = Int32GetDatum(stats.version);
 	values[1] = Int64GetDatum((int64) stats.bucket_pages);
 	values[2] = Int64GetDatum((int64) stats.overflow_pages);
diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c
index cffb6f8310..939d114f02 100644
--- a/contrib/postgres_fdw/connection.c
+++ b/contrib/postgres_fdw/connection.c
@@ -1678,8 +1678,8 @@ postgres_fdw_get_connections(PG_FUNCTION_ARGS)
 	while ((entry = (ConnCacheEntry *) hash_seq_search(&scan)))
 	{
 		ForeignServer *server;
-		Datum		values[POSTGRES_FDW_GET_CONNECTIONS_COLS];
-		bool		nulls[POSTGRES_FDW_GET_CONNECTIONS_COLS];
+		Datum		values[POSTGRES_FDW_GET_CONNECTIONS_COLS] = {0};
+		bool		nulls[POSTGRES_FDW_GET_CONNECTIONS_COLS] = {0};
 
 		/* We only look for open remote connections */
 		if (!entry->conn)
@@ -1687,9 +1687,6 @@ postgres_fdw_get_connections(PG_FUNCTION_ARGS)
 
 		server = GetForeignServerExtended(entry->serverid, FSV_MISSING_OK);
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		/*
 		 * The foreign server may have been dropped in current explicit
 		 * transaction. It is not possible to drop the server from another
diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c
index 955a428e3d..cfac539008 100644
--- a/contrib/postgres_fdw/postgres_fdw.c
+++ b/contrib/postgres_fdw/postgres_fdw.c
@@ -3307,7 +3307,7 @@ estimate_path_cost_size(PlannerInfo *root,
 		{
 			RelOptInfo *outerrel = fpinfo->outerrel;
 			PgFdwRelationInfo *ofpinfo;
-			AggClauseCosts aggcosts;
+			AggClauseCosts aggcosts = {0};
 			double		input_rows;
 			int			numGroupCols;
 			double		numGroups = 1;
@@ -3331,7 +3331,6 @@ estimate_path_cost_size(PlannerInfo *root,
 			input_rows = ofpinfo->rows;
 
 			/* Collect statistics about aggregates for estimating costs. */
-			MemSet(&aggcosts, 0, sizeof(AggClauseCosts));
 			if (root->parse->hasAggs)
 			{
 				get_agg_clause_costs(root, AGGSPLIT_SIMPLE, &aggcosts);
diff --git a/contrib/tablefunc/tablefunc.c b/contrib/tablefunc/tablefunc.c
index e308228bde..6452111e19 100644
--- a/contrib/tablefunc/tablefunc.c
+++ b/contrib/tablefunc/tablefunc.c
@@ -127,9 +127,8 @@ typedef struct crosstab_cat_desc
 
 #define crosstab_HashTableLookup(HASHTAB, CATNAME, CATDESC) \
 do { \
-	crosstab_HashEnt *hentry; char key[MAX_CATNAME_LEN]; \
+	crosstab_HashEnt *hentry; char key[MAX_CATNAME_LEN] = {0}; \
 	\
-	MemSet(key, 0, MAX_CATNAME_LEN); \
 	snprintf(key, MAX_CATNAME_LEN - 1, "%s", CATNAME); \
 	hentry = (crosstab_HashEnt*) hash_search(HASHTAB, \
 										 key, HASH_FIND, NULL); \
@@ -141,9 +140,8 @@ do { \
 
 #define crosstab_HashTableInsert(HASHTAB, CATDESC) \
 do { \
-	crosstab_HashEnt *hentry; bool found; char key[MAX_CATNAME_LEN]; \
+	crosstab_HashEnt *hentry; bool found; char key[MAX_CATNAME_LEN] = {0}; \
 	\
-	MemSet(key, 0, MAX_CATNAME_LEN); \
 	snprintf(key, MAX_CATNAME_LEN - 1, "%s", CATDESC->catname); \
 	hentry = (crosstab_HashEnt*) hash_search(HASHTAB, \
 										 key, HASH_ENTER, &found); \
diff --git a/src/backend/access/nbtree/nbtxlog.c b/src/backend/access/nbtree/nbtxlog.c
index ad489e33b3..14fe2d76c4 100644
--- a/src/backend/access/nbtree/nbtxlog.c
+++ b/src/backend/access/nbtree/nbtxlog.c
@@ -717,7 +717,7 @@ btree_xlog_mark_page_halfdead(uint8 info, XLogReaderState *record)
 	Buffer		buffer;
 	Page		page;
 	BTPageOpaque pageop;
-	IndexTupleData trunctuple;
+	IndexTupleData trunctuple = {0};
 
 	/*
 	 * In normal operation, we would lock all the pages this WAL record
@@ -780,7 +780,6 @@ btree_xlog_mark_page_halfdead(uint8 info, XLogReaderState *record)
 	 * Construct a dummy high key item that points to top parent page (value
 	 * is InvalidBlockNumber when the top parent page is the leaf page itself)
 	 */
-	MemSet(&trunctuple, 0, sizeof(IndexTupleData));
 	trunctuple.t_info = sizeof(IndexTupleData);
 	BTreeTupleSetTopParent(&trunctuple, xlrec->topparent);
 
@@ -898,7 +897,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record)
 		 * we'll delete in the subtree undergoing deletion.
 		 */
 		Buffer		leafbuf;
-		IndexTupleData trunctuple;
+		IndexTupleData trunctuple = {0};
 
 		Assert(!isleaf);
 
@@ -915,7 +914,6 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record)
 		pageop->btpo_cycleid = 0;
 
 		/* Add a dummy hikey item */
-		MemSet(&trunctuple, 0, sizeof(IndexTupleData));
 		trunctuple.t_info = sizeof(IndexTupleData);
 		BTreeTupleSetTopParent(&trunctuple, xlrec->leaftopparent);
 
diff --git a/src/backend/access/transam/twophase.c b/src/backend/access/transam/twophase.c
index 41b31c5c6f..dd330ce260 100644
--- a/src/backend/access/transam/twophase.c
+++ b/src/backend/access/transam/twophase.c
@@ -781,7 +781,7 @@ pg_prepared_xact(PG_FUNCTION_ARGS)
 		GlobalTransaction gxact = &status->array[status->currIdx++];
 		PGPROC	   *proc = &ProcGlobal->allProcs[gxact->pgprocno];
 		Datum		values[5];
-		bool		nulls[5];
+		bool		nulls[5] = {0};
 		HeapTuple	tuple;
 		Datum		result;
 
@@ -791,9 +791,6 @@ pg_prepared_xact(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		values[0] = TransactionIdGetDatum(proc->xid);
 		values[1] = CStringGetTextDatum(gxact->gid);
 		values[2] = TimestampTzGetDatum(gxact->prepared_at);
diff --git a/src/backend/access/transam/xlogfuncs.c b/src/backend/access/transam/xlogfuncs.c
index 02bd919ff6..ed79e3d9a3 100644
--- a/src/backend/access/transam/xlogfuncs.c
+++ b/src/backend/access/transam/xlogfuncs.c
@@ -107,7 +107,7 @@ pg_backup_stop(PG_FUNCTION_ARGS)
 #define PG_STOP_BACKUP_V2_COLS 3
 	TupleDesc	tupdesc;
 	Datum		values[PG_STOP_BACKUP_V2_COLS];
-	bool		nulls[PG_STOP_BACKUP_V2_COLS];
+	bool		nulls[PG_STOP_BACKUP_V2_COLS] = {0};
 
 	bool		waitforarchive = PG_GETARG_BOOL(0);
 	XLogRecPtr	stoppoint;
@@ -117,9 +117,6 @@ pg_backup_stop(PG_FUNCTION_ARGS)
 	if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
 		elog(ERROR, "return type must be a row type");
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	if (status != SESSION_BACKUP_RUNNING)
 		ereport(ERROR,
 				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
diff --git a/src/backend/catalog/aclchk.c b/src/backend/catalog/aclchk.c
index 5f1726c095..0bd4557050 100644
--- a/src/backend/catalog/aclchk.c
+++ b/src/backend/catalog/aclchk.c
@@ -1188,9 +1188,6 @@ SetDefaultACL(InternalDefaultACL *iacls)
 	Acl		   *old_acl;
 	Acl		   *new_acl;
 	HeapTuple	newtuple;
-	Datum		values[Natts_pg_default_acl];
-	bool		nulls[Natts_pg_default_acl];
-	bool		replaces[Natts_pg_default_acl];
 	int			noldmembers;
 	int			nnewmembers;
 	Oid		   *oldmembers;
@@ -1341,13 +1338,10 @@ SetDefaultACL(InternalDefaultACL *iacls)
 	}
 	else
 	{
+		Datum		values[Natts_pg_default_acl] = {0};
+		bool		nulls[Natts_pg_default_acl] = {0};
 		Oid			defAclOid;
 
-		/* Prepare to insert or update pg_default_acl entry */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		if (isNew)
 		{
 			/* insert new entry */
@@ -1364,6 +1358,8 @@ SetDefaultACL(InternalDefaultACL *iacls)
 		}
 		else
 		{
+			bool		replaces[Natts_pg_default_acl] = {0};
+
 			defAclOid = ((Form_pg_default_acl) GETSTRUCT(tuple))->oid;
 
 			/* update existing entry */
@@ -1662,9 +1658,8 @@ ExecGrant_Attribute(InternalGrant *istmt, Oid relOid, const char *relname,
 	AclMode		avail_goptions;
 	bool		need_update;
 	HeapTuple	newtuple;
-	Datum		values[Natts_pg_attribute];
-	bool		nulls[Natts_pg_attribute];
-	bool		replaces[Natts_pg_attribute];
+	Datum		values[Natts_pg_attribute] = {0};
+	bool		nulls[Natts_pg_attribute] = {0};
 	int			noldmembers;
 	int			nnewmembers;
 	Oid		   *oldmembers;
@@ -1745,9 +1740,6 @@ ExecGrant_Attribute(InternalGrant *istmt, Oid relOid, const char *relname,
 	nnewmembers = aclmembers(new_acl, &newmembers);
 
 	/* finished building new ACL value, now insert it */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, false, sizeof(nulls));
-	MemSet(replaces, false, sizeof(replaces));
 
 	/*
 	 * If the updated ACL is empty, we can set attacl to null, and maybe even
@@ -1766,10 +1758,12 @@ ExecGrant_Attribute(InternalGrant *istmt, Oid relOid, const char *relname,
 		nulls[Anum_pg_attribute_attacl - 1] = true;
 		need_update = !isNull;
 	}
-	replaces[Anum_pg_attribute_attacl - 1] = true;
 
 	if (need_update)
 	{
+		bool		replaces[Natts_pg_attribute] = {0};
+
+		replaces[Anum_pg_attribute_attacl - 1] = true;
 		newtuple = heap_modify_tuple(attr_tuple, RelationGetDescr(attRelation),
 									 values, nulls, replaces);
 
@@ -1975,9 +1969,9 @@ ExecGrant_Relation(InternalGrant *istmt)
 			Acl		   *new_acl;
 			Oid			grantorId;
 			HeapTuple	newtuple;
-			Datum		values[Natts_pg_class];
-			bool		nulls[Natts_pg_class];
-			bool		replaces[Natts_pg_class];
+			Datum		values[Natts_pg_class] = {0};
+			bool		nulls[Natts_pg_class] = {0};
+			bool		replaces[Natts_pg_class] = {0};
 			int			nnewmembers;
 			Oid		   *newmembers;
 			ObjectType	objtype;
@@ -2027,10 +2021,6 @@ ExecGrant_Relation(InternalGrant *istmt)
 			nnewmembers = aclmembers(new_acl, &newmembers);
 
 			/* finished building new ACL value, now insert it */
-			MemSet(values, 0, sizeof(values));
-			MemSet(nulls, false, sizeof(nulls));
-			MemSet(replaces, false, sizeof(replaces));
-
 			replaces[Anum_pg_class_relacl - 1] = true;
 			values[Anum_pg_class_relacl - 1] = PointerGetDatum(new_acl);
 
@@ -2129,6 +2119,9 @@ ExecGrant_Relation(InternalGrant *istmt)
 static void
 ExecGrant_Database(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_database] = {0};
+	bool		nulls[Natts_pg_database] = {0};
+	bool		replaces[Natts_pg_database] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -2150,9 +2143,6 @@ ExecGrant_Database(InternalGrant *istmt)
 		Oid			grantorId;
 		Oid			ownerId;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_database];
-		bool		nulls[Natts_pg_database];
-		bool		replaces[Natts_pg_database];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2217,10 +2207,6 @@ ExecGrant_Database(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_database_datacl - 1] = true;
 		values[Anum_pg_database_datacl - 1] = PointerGetDatum(new_acl);
 
@@ -2249,6 +2235,9 @@ ExecGrant_Database(InternalGrant *istmt)
 static void
 ExecGrant_Fdw(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_foreign_data_wrapper] = {0};
+	bool		nulls[Natts_pg_foreign_data_wrapper] = {0};
+	bool		replaces[Natts_pg_foreign_data_wrapper] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -2271,9 +2260,6 @@ ExecGrant_Fdw(InternalGrant *istmt)
 		Oid			ownerId;
 		HeapTuple	tuple;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_foreign_data_wrapper];
-		bool		nulls[Natts_pg_foreign_data_wrapper];
-		bool		replaces[Natts_pg_foreign_data_wrapper];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2339,10 +2325,6 @@ ExecGrant_Fdw(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_foreign_data_wrapper_fdwacl - 1] = true;
 		values[Anum_pg_foreign_data_wrapper_fdwacl - 1] = PointerGetDatum(new_acl);
 
@@ -2376,6 +2358,9 @@ ExecGrant_Fdw(InternalGrant *istmt)
 static void
 ExecGrant_ForeignServer(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_foreign_server] = {0};
+	bool		nulls[Natts_pg_foreign_server] = {0};
+	bool		replaces[Natts_pg_foreign_server] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -2398,9 +2383,6 @@ ExecGrant_ForeignServer(InternalGrant *istmt)
 		Oid			ownerId;
 		HeapTuple	tuple;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_foreign_server];
-		bool		nulls[Natts_pg_foreign_server];
-		bool		replaces[Natts_pg_foreign_server];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2465,10 +2447,6 @@ ExecGrant_ForeignServer(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_foreign_server_srvacl - 1] = true;
 		values[Anum_pg_foreign_server_srvacl - 1] = PointerGetDatum(new_acl);
 
@@ -2501,6 +2479,9 @@ ExecGrant_ForeignServer(InternalGrant *istmt)
 static void
 ExecGrant_Function(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_proc] = {0};
+	bool		nulls[Natts_pg_proc] = {0};
+	bool		replaces[Natts_pg_proc] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -2523,9 +2504,6 @@ ExecGrant_Function(InternalGrant *istmt)
 		Oid			ownerId;
 		HeapTuple	tuple;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_proc];
-		bool		nulls[Natts_pg_proc];
-		bool		replaces[Natts_pg_proc];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2589,10 +2567,6 @@ ExecGrant_Function(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_proc_proacl - 1] = true;
 		values[Anum_pg_proc_proacl - 1] = PointerGetDatum(new_acl);
 
@@ -2624,6 +2598,9 @@ ExecGrant_Function(InternalGrant *istmt)
 static void
 ExecGrant_Language(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_language] = {0};
+	bool		nulls[Natts_pg_language] = {0};
+	bool		replaces[Natts_pg_language] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -2646,9 +2623,6 @@ ExecGrant_Language(InternalGrant *istmt)
 		Oid			ownerId;
 		HeapTuple	tuple;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_language];
-		bool		nulls[Natts_pg_language];
-		bool		replaces[Natts_pg_language];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2720,10 +2694,6 @@ ExecGrant_Language(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_language_lanacl - 1] = true;
 		values[Anum_pg_language_lanacl - 1] = PointerGetDatum(new_acl);
 
@@ -2755,6 +2725,9 @@ ExecGrant_Language(InternalGrant *istmt)
 static void
 ExecGrant_Largeobject(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_largeobject_metadata] = {0};
+	bool		nulls[Natts_pg_largeobject_metadata] = {0};
+	bool		replaces[Natts_pg_largeobject_metadata] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -2778,9 +2751,6 @@ ExecGrant_Largeobject(InternalGrant *istmt)
 		Oid			grantorId;
 		Oid			ownerId;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_largeobject_metadata];
-		bool		nulls[Natts_pg_largeobject_metadata];
-		bool		replaces[Natts_pg_largeobject_metadata];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2858,10 +2828,6 @@ ExecGrant_Largeobject(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_largeobject_metadata_lomacl - 1] = true;
 		values[Anum_pg_largeobject_metadata_lomacl - 1]
 			= PointerGetDatum(new_acl);
@@ -2895,6 +2861,9 @@ ExecGrant_Largeobject(InternalGrant *istmt)
 static void
 ExecGrant_Namespace(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_namespace] = {0};
+	bool		nulls[Natts_pg_namespace] = {0};
+	bool		replaces[Natts_pg_namespace] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -2917,9 +2886,6 @@ ExecGrant_Namespace(InternalGrant *istmt)
 		Oid			ownerId;
 		HeapTuple	tuple;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_namespace];
-		bool		nulls[Natts_pg_namespace];
-		bool		replaces[Natts_pg_namespace];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2984,10 +2950,6 @@ ExecGrant_Namespace(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_namespace_nspacl - 1] = true;
 		values[Anum_pg_namespace_nspacl - 1] = PointerGetDatum(new_acl);
 
@@ -3019,6 +2981,9 @@ ExecGrant_Namespace(InternalGrant *istmt)
 static void
 ExecGrant_Tablespace(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_tablespace] = {0};
+	bool		nulls[Natts_pg_tablespace] = {0};
+	bool		replaces[Natts_pg_tablespace] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -3040,9 +3005,6 @@ ExecGrant_Tablespace(InternalGrant *istmt)
 		Oid			grantorId;
 		Oid			ownerId;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_tablespace];
-		bool		nulls[Natts_pg_tablespace];
-		bool		replaces[Natts_pg_tablespace];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -3108,10 +3070,6 @@ ExecGrant_Tablespace(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_tablespace_spcacl - 1] = true;
 		values[Anum_pg_tablespace_spcacl - 1] = PointerGetDatum(new_acl);
 
@@ -3139,6 +3097,9 @@ ExecGrant_Tablespace(InternalGrant *istmt)
 static void
 ExecGrant_Type(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_type] = {0};
+	bool		nulls[Natts_pg_type] = {0};
+	bool		replaces[Natts_pg_type] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -3160,9 +3121,6 @@ ExecGrant_Type(InternalGrant *istmt)
 		Oid			grantorId;
 		Oid			ownerId;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_type];
-		bool		nulls[Natts_pg_type];
-		bool		replaces[Natts_pg_type];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -3242,10 +3200,6 @@ ExecGrant_Type(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_type_typacl - 1] = true;
 		values[Anum_pg_type_typacl - 1] = PointerGetDatum(new_acl);
 
@@ -3384,13 +3338,9 @@ ExecGrant_Parameter(InternalGrant *istmt)
 		{
 			/* finished building new ACL value, now insert it */
 			HeapTuple	newtuple;
-			Datum		values[Natts_pg_parameter_acl];
-			bool		nulls[Natts_pg_parameter_acl];
-			bool		replaces[Natts_pg_parameter_acl];
-
-			MemSet(values, 0, sizeof(values));
-			MemSet(nulls, false, sizeof(nulls));
-			MemSet(replaces, false, sizeof(replaces));
+			Datum		values[Natts_pg_parameter_acl] = {0};
+			bool		nulls[Natts_pg_parameter_acl] = {0};
+			bool		replaces[Natts_pg_parameter_acl] = {0};
 
 			replaces[Anum_pg_parameter_acl_paracl - 1] = true;
 			values[Anum_pg_parameter_acl_paracl - 1] = PointerGetDatum(new_acl);
@@ -6419,16 +6369,12 @@ recordExtensionInitPrivWorker(Oid objoid, Oid classoid, int objsubid, Acl *new_a
 	/* If we find an entry, update it with the latest ACL. */
 	if (HeapTupleIsValid(oldtuple))
 	{
-		Datum		values[Natts_pg_init_privs];
-		bool		nulls[Natts_pg_init_privs];
-		bool		replace[Natts_pg_init_privs];
-
 		/* If we have a new ACL to set, then update the row with it. */
 		if (new_acl)
 		{
-			MemSet(values, 0, sizeof(values));
-			MemSet(nulls, false, sizeof(nulls));
-			MemSet(replace, false, sizeof(replace));
+			Datum		values[Natts_pg_init_privs] = {0};
+			bool		nulls[Natts_pg_init_privs] = {0};
+			bool		replace[Natts_pg_init_privs] = {0};
 
 			values[Anum_pg_init_privs_initprivs - 1] = PointerGetDatum(new_acl);
 			replace[Anum_pg_init_privs_initprivs - 1] = true;
@@ -6446,9 +6392,6 @@ recordExtensionInitPrivWorker(Oid objoid, Oid classoid, int objsubid, Acl *new_a
 	}
 	else
 	{
-		Datum		values[Natts_pg_init_privs];
-		bool		nulls[Natts_pg_init_privs];
-
 		/*
 		 * Only add a new entry if the new ACL is non-NULL.
 		 *
@@ -6457,9 +6400,10 @@ recordExtensionInitPrivWorker(Oid objoid, Oid classoid, int objsubid, Acl *new_a
 		 */
 		if (new_acl)
 		{
-			/* No entry found, so add it. */
-			MemSet(nulls, false, sizeof(nulls));
+			Datum		values[Natts_pg_init_privs] = {0};
+			bool		nulls[Natts_pg_init_privs] = {0};
 
+			/* No entry found, so add it. */
 			values[Anum_pg_init_privs_objoid - 1] = ObjectIdGetDatum(objoid);
 			values[Anum_pg_init_privs_classoid - 1] = ObjectIdGetDatum(classoid);
 			values[Anum_pg_init_privs_objsubid - 1] = Int32GetDatum(objsubid);
diff --git a/src/backend/catalog/dependency.c b/src/backend/catalog/dependency.c
index de10923391..5cbd72ce10 100644
--- a/src/backend/catalog/dependency.c
+++ b/src/backend/catalog/dependency.c
@@ -1635,12 +1635,11 @@ recordDependencyOnSingleRelExpr(const ObjectAddress *depender,
 								bool reverse_self)
 {
 	find_expr_references_context context;
-	RangeTblEntry rte;
+	RangeTblEntry rte = {0};
 
 	context.addrs = new_object_addresses();
 
 	/* We gin up a rather bogus rangetable list to handle Vars */
-	MemSet(&rte, 0, sizeof(rte));
 	rte.type = T_RangeTblEntry;
 	rte.rtekind = RTE_RELATION;
 	rte.relid = relId;
diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c
index e770ea6eb8..9b03579e6e 100644
--- a/src/backend/catalog/heap.c
+++ b/src/backend/catalog/heap.c
@@ -1709,15 +1709,11 @@ RemoveAttributeById(Oid relid, AttrNumber attnum)
 		/* clear the missing value if any */
 		if (attStruct->atthasmissing)
 		{
-			Datum		valuesAtt[Natts_pg_attribute];
-			bool		nullsAtt[Natts_pg_attribute];
-			bool		replacesAtt[Natts_pg_attribute];
+			Datum		valuesAtt[Natts_pg_attribute] = {0};
+			bool		nullsAtt[Natts_pg_attribute] = {0};
+			bool		replacesAtt[Natts_pg_attribute] = {0};
 
 			/* update the tuple - set atthasmissing and attmissingval */
-			MemSet(valuesAtt, 0, sizeof(valuesAtt));
-			MemSet(nullsAtt, false, sizeof(nullsAtt));
-			MemSet(replacesAtt, false, sizeof(replacesAtt));
-
 			valuesAtt[Anum_pg_attribute_atthasmissing - 1] =
 				BoolGetDatum(false);
 			replacesAtt[Anum_pg_attribute_atthasmissing - 1] = true;
@@ -2006,9 +2002,9 @@ RelationClearMissing(Relation rel)
 void
 SetAttrMissing(Oid relid, char *attname, char *value)
 {
-	Datum		valuesAtt[Natts_pg_attribute];
-	bool		nullsAtt[Natts_pg_attribute];
-	bool		replacesAtt[Natts_pg_attribute];
+	Datum		valuesAtt[Natts_pg_attribute] = {0};
+	bool		nullsAtt[Natts_pg_attribute] = {0};
+	bool		replacesAtt[Natts_pg_attribute] = {0};
 	Datum		missingval;
 	Form_pg_attribute attStruct;
 	Relation	attrrel,
@@ -2041,10 +2037,6 @@ SetAttrMissing(Oid relid, char *attname, char *value)
 								  Int32GetDatum(attStruct->atttypmod));
 
 	/* update the tuple - set atthasmissing and attmissingval */
-	MemSet(valuesAtt, 0, sizeof(valuesAtt));
-	MemSet(nullsAtt, false, sizeof(nullsAtt));
-	MemSet(replacesAtt, false, sizeof(replacesAtt));
-
 	valuesAtt[Anum_pg_attribute_atthasmissing - 1] = BoolGetDatum(true);
 	replacesAtt[Anum_pg_attribute_atthasmissing - 1] = true;
 	valuesAtt[Anum_pg_attribute_attmissingval - 1] = missingval;
@@ -3321,7 +3313,7 @@ StorePartitionKey(Relation rel,
 	Relation	pg_partitioned_table;
 	HeapTuple	tuple;
 	Datum		values[Natts_pg_partitioned_table];
-	bool		nulls[Natts_pg_partitioned_table];
+	bool		nulls[Natts_pg_partitioned_table] = {0};
 	ObjectAddress myself;
 	ObjectAddress referenced;
 	ObjectAddresses *addrs;
@@ -3347,8 +3339,6 @@ StorePartitionKey(Relation rel,
 
 	pg_partitioned_table = table_open(PartitionedRelationId, RowExclusiveLock);
 
-	MemSet(nulls, false, sizeof(nulls));
-
 	/* Only this can ever be NULL */
 	if (!partexprDatum)
 		nulls[Anum_pg_partitioned_table_partexprs - 1] = true;
diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c
index c5d463ac55..d7192f35e3 100644
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@@ -554,7 +554,7 @@ UpdateIndexRelation(Oid indexoid,
 	Datum		exprsDatum;
 	Datum		predDatum;
 	Datum		values[Natts_pg_index];
-	bool		nulls[Natts_pg_index];
+	bool		nulls[Natts_pg_index] = {0};
 	Relation	pg_index;
 	HeapTuple	tuple;
 	int			i;
@@ -608,8 +608,6 @@ UpdateIndexRelation(Oid indexoid,
 	/*
 	 * Build a pg_index tuple
 	 */
-	MemSet(nulls, false, sizeof(nulls));
-
 	values[Anum_pg_index_indexrelid - 1] = ObjectIdGetDatum(indexoid);
 	values[Anum_pg_index_indrelid - 1] = ObjectIdGetDatum(heapoid);
 	values[Anum_pg_index_indnatts - 1] = Int16GetDatum(indexInfo->ii_NumIndexAttrs);
diff --git a/src/backend/catalog/pg_attrdef.c b/src/backend/catalog/pg_attrdef.c
index c5d4a9912e..1a14093a9a 100644
--- a/src/backend/catalog/pg_attrdef.c
+++ b/src/backend/catalog/pg_attrdef.c
@@ -111,15 +111,12 @@ StoreAttrDefault(Relation rel, AttrNumber attnum,
 		Expr	   *expr2 = (Expr *) expr;
 		EState	   *estate = NULL;
 		ExprContext *econtext;
-		Datum		valuesAtt[Natts_pg_attribute];
-		bool		nullsAtt[Natts_pg_attribute];
-		bool		replacesAtt[Natts_pg_attribute];
+		Datum		valuesAtt[Natts_pg_attribute] = {0};
+		bool		nullsAtt[Natts_pg_attribute] = {0};
+		bool		replacesAtt[Natts_pg_attribute] = {0};
 		Datum		missingval = (Datum) 0;
 		bool		missingIsNull = true;
 
-		MemSet(valuesAtt, 0, sizeof(valuesAtt));
-		MemSet(nullsAtt, false, sizeof(nullsAtt));
-		MemSet(replacesAtt, false, sizeof(replacesAtt));
 		valuesAtt[Anum_pg_attribute_atthasdef - 1] = true;
 		replacesAtt[Anum_pg_attribute_atthasdef - 1] = true;
 
diff --git a/src/backend/catalog/pg_cast.c b/src/backend/catalog/pg_cast.c
index 4857f6468d..1812bb7fcc 100644
--- a/src/backend/catalog/pg_cast.c
+++ b/src/backend/catalog/pg_cast.c
@@ -47,7 +47,7 @@ CastCreate(Oid sourcetypeid, Oid targettypeid, Oid funcid, char castcontext,
 	HeapTuple	tuple;
 	Oid			castid;
 	Datum		values[Natts_pg_cast];
-	bool		nulls[Natts_pg_cast];
+	bool		nulls[Natts_pg_cast] = {0};
 	ObjectAddress myself,
 				referenced;
 	ObjectAddresses *addrs;
@@ -78,8 +78,6 @@ CastCreate(Oid sourcetypeid, Oid targettypeid, Oid funcid, char castcontext,
 	values[Anum_pg_cast_castcontext - 1] = CharGetDatum(castcontext);
 	values[Anum_pg_cast_castmethod - 1] = CharGetDatum(castmethod);
 
-	MemSet(nulls, false, sizeof(nulls));
-
 	tuple = heap_form_tuple(RelationGetDescr(relation), values, nulls);
 
 	CatalogTupleInsert(relation, tuple);
diff --git a/src/backend/catalog/pg_parameter_acl.c b/src/backend/catalog/pg_parameter_acl.c
index 2decee909b..0570e811d1 100644
--- a/src/backend/catalog/pg_parameter_acl.c
+++ b/src/backend/catalog/pg_parameter_acl.c
@@ -74,8 +74,8 @@ ParameterAclCreate(const char *parameter)
 	Relation	rel;
 	TupleDesc	tupDesc;
 	HeapTuple	tuple;
-	Datum		values[Natts_pg_parameter_acl];
-	bool		nulls[Natts_pg_parameter_acl];
+	Datum		values[Natts_pg_parameter_acl] = {0};
+	bool		nulls[Natts_pg_parameter_acl] = {0};
 
 	/*
 	 * To prevent cluttering pg_parameter_acl with useless entries, insist
@@ -98,8 +98,6 @@ ParameterAclCreate(const char *parameter)
 	 */
 	rel = table_open(ParameterAclRelationId, RowExclusiveLock);
 	tupDesc = RelationGetDescr(rel);
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, false, sizeof(nulls));
 	parameterId = GetNewOidWithIndex(rel,
 									 ParameterAclOidIndexId,
 									 Anum_pg_parameter_acl_oid);
diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index c365de3a72..4ff692cb5e 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -1162,15 +1162,12 @@ pg_get_publication_tables(PG_FUNCTION_ARGS)
 		HeapTuple	pubtuple = NULL;
 		HeapTuple	rettuple;
 		Oid			relid = list_nth_oid(tables, funcctx->call_cntr);
-		Datum		values[NUM_PUBLICATION_TABLES_ELEM];
-		bool		nulls[NUM_PUBLICATION_TABLES_ELEM];
+		Datum		values[NUM_PUBLICATION_TABLES_ELEM] = {0};
+		bool		nulls[NUM_PUBLICATION_TABLES_ELEM] = {0};
 
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(nulls, 0, sizeof(nulls));
-		MemSet(values, 0, sizeof(values));
-
 		publication = GetPublicationByName(pubname, false);
 
 		values[0] = ObjectIdGetDatum(relid);
diff --git a/src/backend/commands/copyfromparse.c b/src/backend/commands/copyfromparse.c
index 57813b3458..cef0f2c279 100644
--- a/src/backend/commands/copyfromparse.c
+++ b/src/backend/commands/copyfromparse.c
@@ -869,7 +869,7 @@ NextCopyFrom(CopyFromState cstate, ExprContext *econtext,
 
 	/* Initialize all values for row to NULL */
 	MemSet(values, 0, num_phys_attrs * sizeof(Datum));
-	MemSet(nulls, true, num_phys_attrs * sizeof(bool));
+	memset(nulls, true, num_phys_attrs * sizeof(bool));
 
 	if (!cstate->opts.binary)
 	{
diff --git a/src/backend/commands/dbcommands.c b/src/backend/commands/dbcommands.c
index 1901b434c5..099d369b2f 100644
--- a/src/backend/commands/dbcommands.c
+++ b/src/backend/commands/dbcommands.c
@@ -689,8 +689,8 @@ createdb(ParseState *pstate, const CreatedbStmt *stmt)
 	volatile Oid dst_deftablespace;
 	Relation	pg_database_rel;
 	HeapTuple	tuple;
-	Datum		new_record[Natts_pg_database];
-	bool		new_record_nulls[Natts_pg_database];
+	Datum		new_record[Natts_pg_database] = {0};
+	bool		new_record_nulls[Natts_pg_database] = {0};
 	Oid			dboid = InvalidOid;
 	Oid			datdba;
 	ListCell   *option;
@@ -1296,9 +1296,6 @@ createdb(ParseState *pstate, const CreatedbStmt *stmt)
 		   (dblocprovider != COLLPROVIDER_ICU && !dbiculocale));
 
 	/* Form tuple */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-
 	new_record[Anum_pg_database_oid - 1] = ObjectIdGetDatum(dboid);
 	new_record[Anum_pg_database_datname - 1] =
 		DirectFunctionCall1(namein, CStringGetDatum(dbname));
@@ -1822,9 +1819,6 @@ movedb(const char *dbname, const char *tblspcname)
 				newtuple;
 	Oid			src_tblspcoid,
 				dst_tblspcoid;
-	Datum		new_record[Natts_pg_database];
-	bool		new_record_nulls[Natts_pg_database];
-	bool		new_record_repl[Natts_pg_database];
 	ScanKeyData scankey;
 	SysScanDesc sysscan;
 	AclResult	aclresult;
@@ -2003,6 +1997,10 @@ movedb(const char *dbname, const char *tblspcname)
 	PG_ENSURE_ERROR_CLEANUP(movedb_failure_callback,
 							PointerGetDatum(&fparms));
 	{
+		Datum		new_record[Natts_pg_database] = {0};
+		bool		new_record_nulls[Natts_pg_database] = {0};
+		bool		new_record_repl[Natts_pg_database] = {0};
+
 		/*
 		 * Copy files from the old tablespace to the new one
 		 */
@@ -2042,10 +2040,6 @@ movedb(const char *dbname, const char *tblspcname)
 					(errcode(ERRCODE_UNDEFINED_DATABASE),
 					 errmsg("database \"%s\" does not exist", dbname)));
 
-		MemSet(new_record, 0, sizeof(new_record));
-		MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-		MemSet(new_record_repl, false, sizeof(new_record_repl));
-
 		new_record[Anum_pg_database_dattablespace - 1] = ObjectIdGetDatum(dst_tblspcoid);
 		new_record_repl[Anum_pg_database_dattablespace - 1] = true;
 
@@ -2194,9 +2188,9 @@ AlterDatabase(ParseState *pstate, AlterDatabaseStmt *stmt, bool isTopLevel)
 	DefElem    *dallowconnections = NULL;
 	DefElem    *dconnlimit = NULL;
 	DefElem    *dtablespace = NULL;
-	Datum		new_record[Natts_pg_database];
-	bool		new_record_nulls[Natts_pg_database];
-	bool		new_record_repl[Natts_pg_database];
+	Datum		new_record[Natts_pg_database] = {0};
+	bool		new_record_nulls[Natts_pg_database] = {0};
+	bool		new_record_repl[Natts_pg_database] = {0};
 
 	/* Extract options from the statement node tree */
 	foreach(option, stmt->options)
@@ -2305,10 +2299,6 @@ AlterDatabase(ParseState *pstate, AlterDatabaseStmt *stmt, bool isTopLevel)
 	/*
 	 * Build an updated tuple, perusing the information just obtained
 	 */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-	MemSet(new_record_repl, false, sizeof(new_record_repl));
-
 	if (distemplate)
 	{
 		new_record[Anum_pg_database_datistemplate - 1] = BoolGetDatum(dbistemplate);
@@ -2492,8 +2482,8 @@ AlterDatabaseOwner(const char *dbname, Oid newOwnerId)
 	if (datForm->datdba != newOwnerId)
 	{
 		Datum		repl_val[Natts_pg_database];
-		bool		repl_null[Natts_pg_database];
-		bool		repl_repl[Natts_pg_database];
+		bool		repl_null[Natts_pg_database] = {0};
+		bool		repl_repl[Natts_pg_database] = {0};
 		Acl		   *newAcl;
 		Datum		aclDatum;
 		bool		isNull;
@@ -2521,9 +2511,6 @@ AlterDatabaseOwner(const char *dbname, Oid newOwnerId)
 					(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
 					 errmsg("permission denied to change owner of database")));
 
-		memset(repl_null, false, sizeof(repl_null));
-		memset(repl_repl, false, sizeof(repl_repl));
-
 		repl_repl[Anum_pg_database_datdba - 1] = true;
 		repl_val[Anum_pg_database_datdba - 1] = ObjectIdGetDatum(newOwnerId);
 
diff --git a/src/backend/commands/event_trigger.c b/src/backend/commands/event_trigger.c
index f46f86474a..eef3e5d56e 100644
--- a/src/backend/commands/event_trigger.c
+++ b/src/backend/commands/event_trigger.c
@@ -1310,14 +1310,11 @@ pg_event_trigger_dropped_objects(PG_FUNCTION_ARGS)
 	{
 		SQLDropObject *obj;
 		int			i = 0;
-		Datum		values[12];
-		bool		nulls[12];
+		Datum		values[12] = {0};
+		bool		nulls[12] = {0};
 
 		obj = slist_container(SQLDropObject, next, iter.cur);
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		/* classid */
 		values[i++] = ObjectIdGetDatum(obj->address.classId);
 
@@ -1840,7 +1837,7 @@ pg_event_trigger_ddl_commands(PG_FUNCTION_ARGS)
 	{
 		CollectedCommand *cmd = lfirst(lc);
 		Datum		values[9];
-		bool		nulls[9];
+		bool		nulls[9] = {0};
 		ObjectAddress addr;
 		int			i = 0;
 
@@ -1858,8 +1855,6 @@ pg_event_trigger_ddl_commands(PG_FUNCTION_ARGS)
 			!OidIsValid(cmd->d.simple.address.objectId))
 			continue;
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		switch (cmd->type)
 		{
 			case SCT_Simple:
diff --git a/src/backend/commands/functioncmds.c b/src/backend/commands/functioncmds.c
index b016eecb2c..f51cfe6df1 100644
--- a/src/backend/commands/functioncmds.c
+++ b/src/backend/commands/functioncmds.c
@@ -1806,8 +1806,7 @@ CreateTransform(CreateTransformStmt *stmt)
 	AclResult	aclresult;
 	Form_pg_proc procstruct;
 	Datum		values[Natts_pg_transform];
-	bool		nulls[Natts_pg_transform];
-	bool		replaces[Natts_pg_transform];
+	bool		nulls[Natts_pg_transform] = {0};
 	Oid			transformid;
 	HeapTuple	tuple;
 	HeapTuple	newtuple;
@@ -1913,8 +1912,6 @@ CreateTransform(CreateTransformStmt *stmt)
 	values[Anum_pg_transform_trffromsql - 1] = ObjectIdGetDatum(fromsqlfuncid);
 	values[Anum_pg_transform_trftosql - 1] = ObjectIdGetDatum(tosqlfuncid);
 
-	MemSet(nulls, false, sizeof(nulls));
-
 	relation = table_open(TransformRelationId, RowExclusiveLock);
 
 	tuple = SearchSysCache2(TRFTYPELANG,
@@ -1922,6 +1919,8 @@ CreateTransform(CreateTransformStmt *stmt)
 							ObjectIdGetDatum(langid));
 	if (HeapTupleIsValid(tuple))
 	{
+		bool		replaces[Natts_pg_transform] = {0};
+
 		Form_pg_transform form = (Form_pg_transform) GETSTRUCT(tuple);
 
 		if (!stmt->replace)
@@ -1931,7 +1930,6 @@ CreateTransform(CreateTransformStmt *stmt)
 							format_type_be(typeid),
 							stmt->lang)));
 
-		MemSet(replaces, false, sizeof(replaces));
 		replaces[Anum_pg_transform_trffromsql - 1] = true;
 		replaces[Anum_pg_transform_trftosql - 1] = true;
 
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 2333aae467..579825c159 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -685,12 +685,10 @@ pg_prepared_statement(PG_FUNCTION_ARGS)
 		{
 			TupleDesc	result_desc;
 			Datum		values[8];
-			bool		nulls[8];
+			bool		nulls[8] = {0};
 
 			result_desc = prep_stmt->plansource->resultDesc;
 
-			MemSet(nulls, 0, sizeof(nulls));
-
 			values[0] = CStringGetTextDatum(prep_stmt->stmt_name);
 			values[1] = CStringGetTextDatum(prep_stmt->plansource->query_string);
 			values[2] = TimestampTzGetDatum(prep_stmt->prepare_time);
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index ef5b34a312..18f7a4ae86 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -9013,15 +9013,15 @@ ATAddForeignKeyConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
 						  bool recurse, bool recursing, LOCKMODE lockmode)
 {
 	Relation	pkrel;
-	int16		pkattnum[INDEX_MAX_KEYS];
-	int16		fkattnum[INDEX_MAX_KEYS];
-	Oid			pktypoid[INDEX_MAX_KEYS];
-	Oid			fktypoid[INDEX_MAX_KEYS];
-	Oid			opclasses[INDEX_MAX_KEYS];
-	Oid			pfeqoperators[INDEX_MAX_KEYS];
-	Oid			ppeqoperators[INDEX_MAX_KEYS];
-	Oid			ffeqoperators[INDEX_MAX_KEYS];
-	int16		fkdelsetcols[INDEX_MAX_KEYS];
+	int16		pkattnum[INDEX_MAX_KEYS] = {0};
+	int16		fkattnum[INDEX_MAX_KEYS] = {0};
+	Oid			pktypoid[INDEX_MAX_KEYS] = {0};
+	Oid			fktypoid[INDEX_MAX_KEYS] = {0};
+	Oid			opclasses[INDEX_MAX_KEYS] = {0};
+	Oid			pfeqoperators[INDEX_MAX_KEYS] = {0};
+	Oid			ppeqoperators[INDEX_MAX_KEYS] = {0};
+	Oid			ffeqoperators[INDEX_MAX_KEYS] = {0};
+	int16		fkdelsetcols[INDEX_MAX_KEYS] = {0};
 	int			i;
 	int			numfks,
 				numpks,
@@ -9113,16 +9113,6 @@ ATAddForeignKeyConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
 	 * Look up the referencing attributes to make sure they exist, and record
 	 * their attnums and type OIDs.
 	 */
-	MemSet(pkattnum, 0, sizeof(pkattnum));
-	MemSet(fkattnum, 0, sizeof(fkattnum));
-	MemSet(pktypoid, 0, sizeof(pktypoid));
-	MemSet(fktypoid, 0, sizeof(fktypoid));
-	MemSet(opclasses, 0, sizeof(opclasses));
-	MemSet(pfeqoperators, 0, sizeof(pfeqoperators));
-	MemSet(ppeqoperators, 0, sizeof(ppeqoperators));
-	MemSet(ffeqoperators, 0, sizeof(ffeqoperators));
-	MemSet(fkdelsetcols, 0, sizeof(fkdelsetcols));
-
 	numfks = transformColumnNameList(RelationGetRelid(rel),
 									 fkconstraint->fk_attrs,
 									 fkattnum, fktypoid);
@@ -11498,7 +11488,7 @@ validateForeignKeyConstraint(char *conname,
 {
 	TupleTableSlot *slot;
 	TableScanDesc scan;
-	Trigger		trig;
+	Trigger		trig = {0};
 	Snapshot	snapshot;
 	MemoryContext oldcxt;
 	MemoryContext perTupCxt;
@@ -11509,7 +11499,6 @@ validateForeignKeyConstraint(char *conname,
 	/*
 	 * Build a trigger call structure; we'll need it either way.
 	 */
-	MemSet(&trig, 0, sizeof(trig));
 	trig.tgoid = InvalidOid;
 	trig.tgname = conname;
 	trig.tgenabled = TRIGGER_FIRES_ON_ORIGIN;
@@ -12783,15 +12772,11 @@ ATExecAlterColumnType(AlteredTableInfo *tab, Relation rel,
 
 			int			one = 1;
 			bool		isNull;
-			Datum		valuesAtt[Natts_pg_attribute];
-			bool		nullsAtt[Natts_pg_attribute];
-			bool		replacesAtt[Natts_pg_attribute];
+			Datum		valuesAtt[Natts_pg_attribute] = {0};
+			bool		nullsAtt[Natts_pg_attribute] = {0};
+			bool		replacesAtt[Natts_pg_attribute] = {0};
 			HeapTuple	newTup;
 
-			MemSet(valuesAtt, 0, sizeof(valuesAtt));
-			MemSet(nullsAtt, false, sizeof(nullsAtt));
-			MemSet(replacesAtt, false, sizeof(replacesAtt));
-
 			missingval = array_get_element(missingval,
 										   1,
 										   &one,
@@ -19219,7 +19204,7 @@ ATDetachCheckNoForeignKeyRefs(Relation partition)
 		HeapTuple	tuple;
 		Form_pg_constraint constrForm;
 		Relation	rel;
-		Trigger		trig;
+		Trigger		trig = {0};
 
 		tuple = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constrOid));
 		if (!HeapTupleIsValid(tuple))
@@ -19232,7 +19217,6 @@ ATDetachCheckNoForeignKeyRefs(Relation partition)
 		/* prevent data changes into the referencing table until commit */
 		rel = table_open(constrForm->conrelid, ShareLock);
 
-		MemSet(&trig, 0, sizeof(trig));
 		trig.tgoid = InvalidOid;
 		trig.tgname = NameStr(constrForm->conname);
 		trig.tgenabled = TRIGGER_FIRES_ON_ORIGIN;
diff --git a/src/backend/commands/tablespace.c b/src/backend/commands/tablespace.c
index c8bdd9992a..cb7d46089a 100644
--- a/src/backend/commands/tablespace.c
+++ b/src/backend/commands/tablespace.c
@@ -238,7 +238,7 @@ CreateTableSpace(CreateTableSpaceStmt *stmt)
 #ifdef HAVE_SYMLINK
 	Relation	rel;
 	Datum		values[Natts_pg_tablespace];
-	bool		nulls[Natts_pg_tablespace];
+	bool		nulls[Natts_pg_tablespace] = {0};
 	HeapTuple	tuple;
 	Oid			tablespaceoid;
 	char	   *location;
@@ -340,8 +340,6 @@ CreateTableSpace(CreateTableSpaceStmt *stmt)
 	 */
 	rel = table_open(TableSpaceRelationId, RowExclusiveLock);
 
-	MemSet(nulls, false, sizeof(nulls));
-
 	if (IsBinaryUpgrade)
 	{
 		/* Use binary-upgrade override for tablespace oid */
diff --git a/src/backend/commands/typecmds.c b/src/backend/commands/typecmds.c
index 4f5e7c7ccb..4f58d29aa5 100644
--- a/src/backend/commands/typecmds.c
+++ b/src/backend/commands/typecmds.c
@@ -2570,9 +2570,9 @@ AlterDomainDefault(List *names, Node *defaultRaw)
 	Relation	rel;
 	char	   *defaultValue;
 	Node	   *defaultExpr = NULL; /* NULL if no default specified */
-	Datum		new_record[Natts_pg_type];
-	bool		new_record_nulls[Natts_pg_type];
-	bool		new_record_repl[Natts_pg_type];
+	Datum		new_record[Natts_pg_type] = {0};
+	bool		new_record_nulls[Natts_pg_type] = {0};
+	bool		new_record_repl[Natts_pg_type] = {0};
 	HeapTuple	newtuple;
 	Form_pg_type typTup;
 	ObjectAddress address;
@@ -2593,9 +2593,6 @@ AlterDomainDefault(List *names, Node *defaultRaw)
 	checkDomainOwner(tup);
 
 	/* Setup new tuple */
-	MemSet(new_record, (Datum) 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-	MemSet(new_record_repl, false, sizeof(new_record_repl));
 
 	/* Store the new default into the tuple */
 	if (defaultRaw)
diff --git a/src/backend/commands/user.c b/src/backend/commands/user.c
index 984305ba31..8f4cc86eda 100644
--- a/src/backend/commands/user.c
+++ b/src/backend/commands/user.c
@@ -74,8 +74,8 @@ CreateRole(ParseState *pstate, CreateRoleStmt *stmt)
 	Relation	pg_authid_rel;
 	TupleDesc	pg_authid_dsc;
 	HeapTuple	tuple;
-	Datum		new_record[Natts_pg_authid];
-	bool		new_record_nulls[Natts_pg_authid];
+	Datum		new_record[Natts_pg_authid] = {0};
+	bool		new_record_nulls[Natts_pg_authid] = {0};
 	Oid			roleid;
 	ListCell   *item;
 	ListCell   *option;
@@ -338,12 +338,8 @@ CreateRole(ParseState *pstate, CreateRoleStmt *stmt)
 	/*
 	 * Build a tuple to insert
 	 */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-
 	new_record[Anum_pg_authid_rolname - 1] =
 		DirectFunctionCall1(namein, CStringGetDatum(stmt->role));
-
 	new_record[Anum_pg_authid_rolsuper - 1] = BoolGetDatum(issuper);
 	new_record[Anum_pg_authid_rolinherit - 1] = BoolGetDatum(inherit);
 	new_record[Anum_pg_authid_rolcreaterole - 1] = BoolGetDatum(createrole);
@@ -492,9 +488,9 @@ CreateRole(ParseState *pstate, CreateRoleStmt *stmt)
 Oid
 AlterRole(ParseState *pstate, AlterRoleStmt *stmt)
 {
-	Datum		new_record[Natts_pg_authid];
-	bool		new_record_nulls[Natts_pg_authid];
-	bool		new_record_repl[Natts_pg_authid];
+	Datum		new_record[Natts_pg_authid] = {0};
+	bool		new_record_nulls[Natts_pg_authid] = {0};
+	bool		new_record_repl[Natts_pg_authid] = {0};
 	Relation	pg_authid_rel;
 	TupleDesc	pg_authid_dsc;
 	HeapTuple	tuple,
@@ -691,9 +687,6 @@ AlterRole(ParseState *pstate, AlterRoleStmt *stmt)
 	/*
 	 * Build an updated tuple, perusing the information just obtained
 	 */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-	MemSet(new_record_repl, false, sizeof(new_record_repl));
 
 	/*
 	 * issuper/createrole/etc
@@ -1440,9 +1433,8 @@ AddRoleMems(const char *rolename, Oid roleid,
 		Oid			memberid = lfirst_oid(iditem);
 		HeapTuple	authmem_tuple;
 		HeapTuple	tuple;
-		Datum		new_record[Natts_pg_auth_members];
-		bool		new_record_nulls[Natts_pg_auth_members];
-		bool		new_record_repl[Natts_pg_auth_members];
+		Datum		new_record[Natts_pg_auth_members] = {0};
+		bool		new_record_nulls[Natts_pg_auth_members] = {0};
 
 		/*
 		 * pg_database_owner is never a role member.  Lifting this restriction
@@ -1500,10 +1492,6 @@ AddRoleMems(const char *rolename, Oid roleid,
 		}
 
 		/* Build a tuple to insert or update */
-		MemSet(new_record, 0, sizeof(new_record));
-		MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-		MemSet(new_record_repl, false, sizeof(new_record_repl));
-
 		new_record[Anum_pg_auth_members_roleid - 1] = ObjectIdGetDatum(roleid);
 		new_record[Anum_pg_auth_members_member - 1] = ObjectIdGetDatum(memberid);
 		new_record[Anum_pg_auth_members_grantor - 1] = ObjectIdGetDatum(grantorId);
@@ -1511,6 +1499,8 @@ AddRoleMems(const char *rolename, Oid roleid,
 
 		if (HeapTupleIsValid(authmem_tuple))
 		{
+			bool		new_record_repl[Natts_pg_auth_members] = {0};
+
 			new_record_repl[Anum_pg_auth_members_grantor - 1] = true;
 			new_record_repl[Anum_pg_auth_members_admin_option - 1] = true;
 			tuple = heap_modify_tuple(authmem_tuple, pg_authmem_dsc,
@@ -1614,15 +1604,11 @@ DelRoleMems(const char *rolename, Oid roleid,
 		{
 			/* Just turn off the admin option */
 			HeapTuple	tuple;
-			Datum		new_record[Natts_pg_auth_members];
-			bool		new_record_nulls[Natts_pg_auth_members];
-			bool		new_record_repl[Natts_pg_auth_members];
+			Datum		new_record[Natts_pg_auth_members] = {0};
+			bool		new_record_nulls[Natts_pg_auth_members] = {0};
+			bool		new_record_repl[Natts_pg_auth_members] = {0};
 
 			/* Build a tuple to update with */
-			MemSet(new_record, 0, sizeof(new_record));
-			MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-			MemSet(new_record_repl, false, sizeof(new_record_repl));
-
 			new_record[Anum_pg_auth_members_admin_option - 1] = BoolGetDatum(false);
 			new_record_repl[Anum_pg_auth_members_admin_option - 1] = true;
 
diff --git a/src/backend/libpq/auth.c b/src/backend/libpq/auth.c
index 2d9ab7edce..53fb7ca628 100644
--- a/src/backend/libpq/auth.c
+++ b/src/backend/libpq/auth.c
@@ -3022,7 +3022,7 @@ PerformRadiusTransaction(const char *server, const char *secret, const char *por
 	struct sockaddr_in localaddr;
 	struct sockaddr_in remoteaddr;
 #endif
-	struct addrinfo hint;
+	struct addrinfo hint = {0};
 	struct addrinfo *serveraddrs;
 	int			port;
 	socklen_t	addrsize;
@@ -3038,7 +3038,6 @@ PerformRadiusTransaction(const char *server, const char *secret, const char *por
 	if (identifier == NULL)
 		identifier = "postgresql";
 
-	MemSet(&hint, 0, sizeof(hint));
 	hint.ai_socktype = SOCK_DGRAM;
 	hint.ai_family = AF_UNSPEC;
 	port = atoi(portstr);
diff --git a/src/backend/libpq/pqcomm.c b/src/backend/libpq/pqcomm.c
index 75392a8bb7..803d166640 100644
--- a/src/backend/libpq/pqcomm.c
+++ b/src/backend/libpq/pqcomm.c
@@ -331,7 +331,7 @@ StreamServerPort(int family, const char *hostName, unsigned short portNumber,
 	char	   *service;
 	struct addrinfo *addrs = NULL,
 			   *addr;
-	struct addrinfo hint;
+	struct addrinfo hint = {0};
 	int			listen_index = 0;
 	int			added = 0;
 
@@ -343,7 +343,6 @@ StreamServerPort(int family, const char *hostName, unsigned short portNumber,
 #endif
 
 	/* Initialize hint structure */
-	MemSet(&hint, 0, sizeof(hint));
 	hint.ai_family = family;
 	hint.ai_flags = AI_PASSIVE;
 	hint.ai_socktype = SOCK_STREAM;
diff --git a/src/backend/optimizer/path/costsize.c b/src/backend/optimizer/path/costsize.c
index fcc26b01a4..1e0f1880c5 100644
--- a/src/backend/optimizer/path/costsize.c
+++ b/src/backend/optimizer/path/costsize.c
@@ -2926,13 +2926,12 @@ cost_agg(Path *path, PlannerInfo *root,
 	double		output_tuples;
 	Cost		startup_cost;
 	Cost		total_cost;
-	AggClauseCosts dummy_aggcosts;
+	const AggClauseCosts dummy_aggcosts = {0};
 
 	/* Use all-zero per-aggregate costs if NULL is passed */
 	if (aggcosts == NULL)
 	{
 		Assert(aggstrategy == AGG_HASHED);
-		MemSet(&dummy_aggcosts, 0, sizeof(AggClauseCosts));
 		aggcosts = &dummy_aggcosts;
 	}
 
diff --git a/src/backend/optimizer/path/indxpath.c b/src/backend/optimizer/path/indxpath.c
index 0ef70ad7f1..9c1b6305d3 100644
--- a/src/backend/optimizer/path/indxpath.c
+++ b/src/backend/optimizer/path/indxpath.c
@@ -238,9 +238,6 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
 	List	   *bitindexpaths;
 	List	   *bitjoinpaths;
 	List	   *joinorclauses;
-	IndexClauseSet rclauseset;
-	IndexClauseSet jclauseset;
-	IndexClauseSet eclauseset;
 	ListCell   *lc;
 
 	/* Skip the whole mess if no indexes */
@@ -253,6 +250,9 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
 	/* Examine each index in turn */
 	foreach(lc, rel->indexlist)
 	{
+		IndexClauseSet rclauseset = {0};
+		IndexClauseSet jclauseset = {0};
+		IndexClauseSet eclauseset = {0};
 		IndexOptInfo *index = (IndexOptInfo *) lfirst(lc);
 
 		/* Protect limited-size array in IndexClauseSets */
@@ -269,7 +269,6 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
 		/*
 		 * Identify the restriction clauses that can match the index.
 		 */
-		MemSet(&rclauseset, 0, sizeof(rclauseset));
 		match_restriction_clauses_to_index(root, index, &rclauseset);
 
 		/*
@@ -286,7 +285,6 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
 		 * step finds only "loose" join clauses that have not been merged into
 		 * EquivalenceClasses.  Also, collect join OR clauses for later.
 		 */
-		MemSet(&jclauseset, 0, sizeof(jclauseset));
 		match_join_clauses_to_index(root, rel, index,
 									&jclauseset, &joinorclauses);
 
@@ -294,7 +292,6 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
 		 * Look for EquivalenceClasses that can generate joinclauses matching
 		 * the index.
 		 */
-		MemSet(&eclauseset, 0, sizeof(eclauseset));
 		match_eclass_clauses_to_index(root, index,
 									  &eclauseset);
 
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c
index 06ad856eac..77cbe681e5 100644
--- a/src/backend/optimizer/plan/planner.c
+++ b/src/backend/optimizer/plan/planner.c
@@ -3350,9 +3350,8 @@ create_grouping_paths(PlannerInfo *root,
 	Query	   *parse = root->parse;
 	RelOptInfo *grouped_rel;
 	RelOptInfo *partially_grouped_rel;
-	AggClauseCosts agg_costs;
+	AggClauseCosts agg_costs = {0};
 
-	MemSet(&agg_costs, 0, sizeof(AggClauseCosts));
 	get_agg_clause_costs(root, AGGSPLIT_SIMPLE, &agg_costs);
 
 	/*
@@ -5908,16 +5907,14 @@ expression_planner_with_deps(Expr *expr,
 							 List **invalItems)
 {
 	Node	   *result;
-	PlannerGlobal glob;
-	PlannerInfo root;
+	PlannerGlobal glob = {0};
+	PlannerInfo root = {0};
 
 	/* Make up dummy planner state so we can use setrefs machinery */
-	MemSet(&glob, 0, sizeof(glob));
 	glob.type = T_PlannerGlobal;
 	glob.relationOids = NIL;
 	glob.invalItems = NIL;
 
-	MemSet(&root, 0, sizeof(root));
 	root.type = T_PlannerInfo;
 	root.glob = &glob;
 
diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c
index 9cef92cab2..f7fb2b3e6d 100644
--- a/src/backend/optimizer/plan/setrefs.c
+++ b/src/backend/optimizer/plan/setrefs.c
@@ -3285,18 +3285,16 @@ extract_query_dependencies(Node *query,
 						   List **invalItems,
 						   bool *hasRowSecurity)
 {
-	PlannerGlobal glob;
-	PlannerInfo root;
+	PlannerGlobal glob = {0};
+	PlannerInfo root = {0};
 
 	/* Make up dummy planner state so we can use this module's machinery */
-	MemSet(&glob, 0, sizeof(glob));
 	glob.type = T_PlannerGlobal;
 	glob.relationOids = NIL;
 	glob.invalItems = NIL;
 	/* Hack: we use glob.dependsOnRole to collect hasRowSecurity flags */
 	glob.dependsOnRole = false;
 
-	MemSet(&root, 0, sizeof(root));
 	root.type = T_PlannerInfo;
 	root.glob = &glob;
 
diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c
index 2a1d44b813..d69cb58b6a 100644
--- a/src/backend/parser/parse_target.c
+++ b/src/backend/parser/parse_target.c
@@ -1594,9 +1594,8 @@ expandRecordVariable(ParseState *pstate, Var *var, int levelsup)
 					 * to.  We have to build an additional level of ParseState
 					 * to keep in step with varlevelsup in the subselect.
 					 */
-					ParseState	mypstate;
+					ParseState	mypstate = {0};
 
-					MemSet(&mypstate, 0, sizeof(mypstate));
 					mypstate.parentParseState = pstate;
 					mypstate.p_rtable = rte->subquery->rtable;
 					/* don't bother filling the rest of the fake pstate */
@@ -1649,10 +1648,9 @@ expandRecordVariable(ParseState *pstate, Var *var, int levelsup)
 					 * in step with varlevelsup in the CTE; furthermore it
 					 * could be an outer CTE.
 					 */
-					ParseState	mypstate;
+					ParseState	mypstate = {0};
 					Index		levelsup;
 
-					MemSet(&mypstate, 0, sizeof(mypstate));
 					/* this loop must work, since GetCTEForRTE did */
 					for (levelsup = 0;
 						 levelsup < rte->ctelevelsup + netlevelsup;
diff --git a/src/backend/replication/logical/launcher.c b/src/backend/replication/logical/launcher.c
index 2bdab53e19..3bbd522724 100644
--- a/src/backend/replication/logical/launcher.c
+++ b/src/backend/replication/logical/launcher.c
@@ -938,8 +938,8 @@ pg_stat_get_subscription(PG_FUNCTION_ARGS)
 	for (i = 0; i < max_logical_replication_workers; i++)
 	{
 		/* for each row */
-		Datum		values[PG_STAT_GET_SUBSCRIPTION_COLS];
-		bool		nulls[PG_STAT_GET_SUBSCRIPTION_COLS];
+		Datum		values[PG_STAT_GET_SUBSCRIPTION_COLS] = {0};
+		bool		nulls[PG_STAT_GET_SUBSCRIPTION_COLS] = {0};
 		int			worker_pid;
 		LogicalRepWorker worker;
 
@@ -953,9 +953,6 @@ pg_stat_get_subscription(PG_FUNCTION_ARGS)
 
 		worker_pid = worker.proc->pid;
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		values[0] = ObjectIdGetDatum(worker.subid);
 		if (OidIsValid(worker.relid))
 			values[1] = ObjectIdGetDatum(worker.relid);
diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c
index 3c407ab964..ef2ca3fef7 100644
--- a/src/backend/replication/walsender.c
+++ b/src/backend/replication/walsender.c
@@ -402,7 +402,7 @@ IdentifySystem(void)
 	TupOutputState *tstate;
 	TupleDesc	tupdesc;
 	Datum		values[4];
-	bool		nulls[4];
+	bool		nulls[4] = {0};
 	TimeLineID	currTLI;
 
 	/*
@@ -437,7 +437,6 @@ IdentifySystem(void)
 	}
 
 	dest = CreateDestReceiver(DestRemoteSimple);
-	MemSet(nulls, false, sizeof(nulls));
 
 	/* need a tuple descriptor representing four columns */
 	tupdesc = CreateTemplateTupleDesc(4);
@@ -483,7 +482,7 @@ ReadReplicationSlot(ReadReplicationSlotCmd *cmd)
 	DestReceiver *dest;
 	TupOutputState *tstate;
 	TupleDesc	tupdesc;
-	Datum		values[READ_REPLICATION_SLOT_COLS];
+	Datum		values[READ_REPLICATION_SLOT_COLS] = {0};
 	bool		nulls[READ_REPLICATION_SLOT_COLS];
 
 	tupdesc = CreateTemplateTupleDesc(READ_REPLICATION_SLOT_COLS);
@@ -495,8 +494,7 @@ ReadReplicationSlot(ReadReplicationSlotCmd *cmd)
 	TupleDescInitBuiltinEntry(tupdesc, (AttrNumber) 3, "restart_tli",
 							  INT8OID, -1, 0);
 
-	MemSet(values, 0, READ_REPLICATION_SLOT_COLS * sizeof(Datum));
-	MemSet(nulls, true, READ_REPLICATION_SLOT_COLS * sizeof(bool));
+	memset(nulls, true, READ_REPLICATION_SLOT_COLS * sizeof(bool));
 
 	LWLockAcquire(ReplicationSlotControlLock, LW_SHARED);
 	slot = SearchNamedReplicationSlot(cmd->slotname, false);
@@ -859,13 +857,12 @@ StartReplication(StartReplicationCmd *cmd)
 		TupOutputState *tstate;
 		TupleDesc	tupdesc;
 		Datum		values[2];
-		bool		nulls[2];
+		bool		nulls[2] = {0};
 
 		snprintf(startpos_str, sizeof(startpos_str), "%X/%X",
 				 LSN_FORMAT_ARGS(sendTimeLineValidUpto));
 
 		dest = CreateDestReceiver(DestRemoteSimple);
-		MemSet(nulls, false, sizeof(nulls));
 
 		/*
 		 * Need a tuple descriptor representing two columns. int8 may seem
@@ -1043,7 +1040,7 @@ CreateReplicationSlot(CreateReplicationSlotCmd *cmd)
 	TupOutputState *tstate;
 	TupleDesc	tupdesc;
 	Datum		values[4];
-	bool		nulls[4];
+	bool		nulls[4] = {0};
 
 	Assert(!MyReplicationSlot);
 
@@ -1178,7 +1175,6 @@ CreateReplicationSlot(CreateReplicationSlotCmd *cmd)
 			 LSN_FORMAT_ARGS(MyReplicationSlot->data.confirmed_flush));
 
 	dest = CreateDestReceiver(DestRemoteSimple);
-	MemSet(nulls, false, sizeof(nulls));
 
 	/*----------
 	 * Need a tuple descriptor representing four columns:
@@ -3527,7 +3523,6 @@ pg_stat_get_wal_senders(PG_FUNCTION_ARGS)
 			}
 		}
 
-		memset(nulls, 0, sizeof(nulls));
 		values[0] = Int32GetDatum(pid);
 
 		if (!has_privs_of_role(GetUserId(), ROLE_PG_READ_ALL_STATS))
@@ -3537,10 +3532,12 @@ pg_stat_get_wal_senders(PG_FUNCTION_ARGS)
 			 * can see details. Other users only get the pid value to know
 			 * it's a walsender, but no details.
 			 */
-			MemSet(&nulls[1], true, PG_STAT_GET_WAL_SENDERS_COLS - 1);
+			nulls[0] = false;
+			memset(&nulls[1], true, PG_STAT_GET_WAL_SENDERS_COLS - 1);
 		}
 		else
 		{
+			memset(nulls, 0, sizeof(nulls));
 			values[1] = CStringGetTextDatum(WalSndGetStateString(state));
 
 			if (XLogRecPtrIsInvalid(sentPtr))
diff --git a/src/backend/rewrite/rewriteDefine.c b/src/backend/rewrite/rewriteDefine.c
index 185bf5fbff..a5a1fb887f 100644
--- a/src/backend/rewrite/rewriteDefine.c
+++ b/src/backend/rewrite/rewriteDefine.c
@@ -67,8 +67,7 @@ InsertRule(const char *rulname,
 	char	   *evqual = nodeToString(event_qual);
 	char	   *actiontree = nodeToString((Node *) action);
 	Datum		values[Natts_pg_rewrite];
-	bool		nulls[Natts_pg_rewrite];
-	bool		replaces[Natts_pg_rewrite];
+	bool		nulls[Natts_pg_rewrite] = {0};
 	NameData	rname;
 	Relation	pg_rewrite_desc;
 	HeapTuple	tup,
@@ -81,8 +80,6 @@ InsertRule(const char *rulname,
 	/*
 	 * Set up *nulls and *values arrays
 	 */
-	MemSet(nulls, false, sizeof(nulls));
-
 	namestrcpy(&rname, rulname);
 	values[Anum_pg_rewrite_rulename - 1] = NameGetDatum(&rname);
 	values[Anum_pg_rewrite_ev_class - 1] = ObjectIdGetDatum(eventrel_oid);
@@ -106,6 +103,8 @@ InsertRule(const char *rulname,
 
 	if (HeapTupleIsValid(oldtup))
 	{
+		bool		replaces[Natts_pg_rewrite] = {0};
+
 		if (!replace)
 			ereport(ERROR,
 					(errcode(ERRCODE_DUPLICATE_OBJECT),
@@ -115,7 +114,6 @@ InsertRule(const char *rulname,
 		/*
 		 * When replacing, we don't need to replace every attribute
 		 */
-		MemSet(replaces, false, sizeof(replaces));
 		replaces[Anum_pg_rewrite_ev_type - 1] = true;
 		replaces[Anum_pg_rewrite_is_instead - 1] = true;
 		replaces[Anum_pg_rewrite_ev_qual - 1] = true;
diff --git a/src/backend/storage/lmgr/lock.c b/src/backend/storage/lmgr/lock.c
index 5f5803f681..ae6a1b1116 100644
--- a/src/backend/storage/lmgr/lock.c
+++ b/src/backend/storage/lmgr/lock.c
@@ -597,13 +597,12 @@ DoLockModesConflict(LOCKMODE mode1, LOCKMODE mode2)
 bool
 LockHeldByMe(const LOCKTAG *locktag, LOCKMODE lockmode)
 {
-	LOCALLOCKTAG localtag;
+	LOCALLOCKTAG localtag = {0};
 	LOCALLOCK  *locallock;
 
 	/*
 	 * See if there is a LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
@@ -635,7 +634,7 @@ LockHasWaiters(const LOCKTAG *locktag, LOCKMODE lockmode, bool sessionLock)
 {
 	LOCKMETHODID lockmethodid = locktag->locktag_lockmethodid;
 	LockMethod	lockMethodTable;
-	LOCALLOCKTAG localtag;
+	LOCALLOCKTAG localtag = {0};
 	LOCALLOCK  *locallock;
 	LOCK	   *lock;
 	PROCLOCK   *proclock;
@@ -658,7 +657,6 @@ LockHasWaiters(const LOCKTAG *locktag, LOCKMODE lockmode, bool sessionLock)
 	/*
 	 * Find the LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
@@ -777,7 +775,7 @@ LockAcquireExtended(const LOCKTAG *locktag,
 {
 	LOCKMETHODID lockmethodid = locktag->locktag_lockmethodid;
 	LockMethod	lockMethodTable;
-	LOCALLOCKTAG localtag;
+	LOCALLOCKTAG localtag = {0};
 	LOCALLOCK  *locallock;
 	LOCK	   *lock;
 	PROCLOCK   *proclock;
@@ -820,7 +818,6 @@ LockAcquireExtended(const LOCKTAG *locktag,
 	/*
 	 * Find or create a LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
@@ -1976,7 +1973,7 @@ LockRelease(const LOCKTAG *locktag, LOCKMODE lockmode, bool sessionLock)
 {
 	LOCKMETHODID lockmethodid = locktag->locktag_lockmethodid;
 	LockMethod	lockMethodTable;
-	LOCALLOCKTAG localtag;
+	LOCALLOCKTAG localtag = {0};
 	LOCALLOCK  *locallock;
 	LOCK	   *lock;
 	PROCLOCK   *proclock;
@@ -1999,7 +1996,6 @@ LockRelease(const LOCKTAG *locktag, LOCKMODE lockmode, bool sessionLock)
 	/*
 	 * Find the LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
diff --git a/src/backend/storage/lmgr/lwlock.c b/src/backend/storage/lmgr/lwlock.c
index fc5c76a48f..ccaa99b453 100644
--- a/src/backend/storage/lmgr/lwlock.c
+++ b/src/backend/storage/lmgr/lwlock.c
@@ -384,7 +384,7 @@ print_lwlock_stats(int code, Datum arg)
 static lwlock_stats *
 get_lwlock_stats_entry(LWLock *lock)
 {
-	lwlock_stats_key key;
+	lwlock_stats_key key = {0};
 	lwlock_stats *lwstats;
 	bool		found;
 
@@ -397,7 +397,6 @@ get_lwlock_stats_entry(LWLock *lock)
 		return &lwlock_stats_dummy;
 
 	/* Fetch or create the entry. */
-	MemSet(&key, 0, sizeof(key));
 	key.tranche = lock->tranche;
 	key.instance = lock;
 	lwstats = hash_search(lwlock_stats_htab, &key, HASH_ENTER, &found);
diff --git a/src/backend/utils/adt/acl.c b/src/backend/utils/adt/acl.c
index b7fd3bcf05..6fa58dd8eb 100644
--- a/src/backend/utils/adt/acl.c
+++ b/src/backend/utils/adt/acl.c
@@ -1785,7 +1785,7 @@ aclexplode(PG_FUNCTION_ARGS)
 		{
 			Datum		result;
 			Datum		values[4];
-			bool		nulls[4];
+			bool		nulls[4] = {0};
 			HeapTuple	tuple;
 
 			values[0] = ObjectIdGetDatum(aidata->ai_grantor);
@@ -1793,8 +1793,6 @@ aclexplode(PG_FUNCTION_ARGS)
 			values[2] = CStringGetTextDatum(convert_aclright_to_string(priv_bit));
 			values[3] = BoolGetDatum((ACLITEM_GET_GOPTIONS(*aidata) & priv_bit) != 0);
 
-			MemSet(nulls, 0, sizeof(nulls));
-
 			tuple = heap_form_tuple(funcctx->tuple_desc, values, nulls);
 			result = HeapTupleGetDatum(tuple);
 
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index b0c37ede87..fb167f226a 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -742,11 +742,10 @@ ReadArrayStr(char *arrayStr,
 	bool		eoArray = false;
 	bool		hasnull;
 	int32		totbytes;
-	int			indx[MAXDIM],
+	int			indx[MAXDIM] = {0},
 				prod[MAXDIM];
 
 	mda_get_prod(ndim, dim, prod);
-	MemSet(indx, 0, sizeof(indx));
 
 	/* Initialize is-null markers to true */
 	memset(nulls, true, nitems * sizeof(bool));
diff --git a/src/backend/utils/adt/datetime.c b/src/backend/utils/adt/datetime.c
index 4c12c4d663..8976f4e9f7 100644
--- a/src/backend/utils/adt/datetime.c
+++ b/src/backend/utils/adt/datetime.c
@@ -4924,13 +4924,13 @@ pg_timezone_abbrevs(PG_FUNCTION_ARGS)
 	Datum		result;
 	HeapTuple	tuple;
 	Datum		values[3];
-	bool		nulls[3];
+	bool		nulls[3] = {0};
 	const datetkn *tp;
 	char		buffer[TOKMAXLEN + 1];
 	int			gmtoffset;
 	bool		is_dst;
 	unsigned char *p;
-	struct pg_itm_in itm_in;
+	struct pg_itm_in itm_in = {0};
 	Interval   *resInterval;
 
 	/* stuff done only on the first call of the function */
@@ -5011,8 +5011,6 @@ pg_timezone_abbrevs(PG_FUNCTION_ARGS)
 			break;
 	}
 
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/*
 	 * Convert name to text, using upcasing conversion that is the inverse of
 	 * what ParseDateTime() uses.
@@ -5024,7 +5022,6 @@ pg_timezone_abbrevs(PG_FUNCTION_ARGS)
 	values[0] = CStringGetTextDatum(buffer);
 
 	/* Convert offset (in seconds) to an interval; can't overflow */
-	MemSet(&itm_in, 0, sizeof(struct pg_itm_in));
 	itm_in.tm_usec = (int64) gmtoffset * USECS_PER_SEC;
 	resInterval = (Interval *) palloc(sizeof(Interval));
 	(void) itmin2interval(&itm_in, resInterval);
@@ -5051,13 +5048,13 @@ pg_timezone_names(PG_FUNCTION_ARGS)
 	pg_tzenum  *tzenum;
 	pg_tz	   *tz;
 	Datum		values[4];
-	bool		nulls[4];
+	bool		nulls[4] = {0};
 	int			tzoff;
 	struct pg_tm tm;
 	fsec_t		fsec;
 	const char *tzn;
 	Interval   *resInterval;
-	struct pg_itm_in itm_in;
+	struct pg_itm_in itm_in = {0};
 
 	SetSingleFuncCall(fcinfo, 0);
 
@@ -5088,13 +5085,10 @@ pg_timezone_names(PG_FUNCTION_ARGS)
 		if (tzn && strlen(tzn) > 31)
 			continue;
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		values[0] = CStringGetTextDatum(pg_get_timezone_name(tz));
 		values[1] = CStringGetTextDatum(tzn ? tzn : "");
 
 		/* Convert tzoff to an interval; can't overflow */
-		MemSet(&itm_in, 0, sizeof(struct pg_itm_in));
 		itm_in.tm_usec = (int64) -tzoff * USECS_PER_SEC;
 		resInterval = (Interval *) palloc(sizeof(Interval));
 		(void) itmin2interval(&itm_in, resInterval);
diff --git a/src/backend/utils/adt/lockfuncs.c b/src/backend/utils/adt/lockfuncs.c
index dedee7af5c..613f5f9bec 100644
--- a/src/backend/utils/adt/lockfuncs.c
+++ b/src/backend/utils/adt/lockfuncs.c
@@ -172,8 +172,8 @@ pg_lock_status(PG_FUNCTION_ARGS)
 		LOCKMODE	mode = 0;
 		const char *locktypename;
 		char		tnbuf[32];
-		Datum		values[NUM_LOCK_STATUS_COLUMNS];
-		bool		nulls[NUM_LOCK_STATUS_COLUMNS];
+		Datum		values[NUM_LOCK_STATUS_COLUMNS] = {0};
+		bool		nulls[NUM_LOCK_STATUS_COLUMNS] = {0};
 		HeapTuple	tuple;
 		Datum		result;
 		LockInstanceData *instance;
@@ -230,9 +230,6 @@ pg_lock_status(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-
 		if (instance->locktag.locktag_type <= LOCKTAG_LAST_TYPE)
 			locktypename = LockTagTypeNames[instance->locktag.locktag_type];
 		else
@@ -359,8 +356,8 @@ pg_lock_status(PG_FUNCTION_ARGS)
 
 		PREDICATELOCKTARGETTAG *predTag = &(predLockData->locktags[mystatus->predLockIdx]);
 		SERIALIZABLEXACT *xact = &(predLockData->xacts[mystatus->predLockIdx]);
-		Datum		values[NUM_LOCK_STATUS_COLUMNS];
-		bool		nulls[NUM_LOCK_STATUS_COLUMNS];
+		Datum		values[NUM_LOCK_STATUS_COLUMNS] = {0};
+		bool		nulls[NUM_LOCK_STATUS_COLUMNS] = {0};
 		HeapTuple	tuple;
 		Datum		result;
 
@@ -369,8 +366,6 @@ pg_lock_status(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
 
 		/* lock type */
 		lockType = GET_PREDICATELOCKTARGETTAG_TYPE(*predTag);
diff --git a/src/backend/utils/adt/partitionfuncs.c b/src/backend/utils/adt/partitionfuncs.c
index 0243bc061f..109dc8023e 100644
--- a/src/backend/utils/adt/partitionfuncs.c
+++ b/src/backend/utils/adt/partitionfuncs.c
@@ -113,8 +113,8 @@ pg_partition_tree(PG_FUNCTION_ARGS)
 	if (funcctx->call_cntr < list_length(partitions))
 	{
 		Datum		result;
-		Datum		values[PG_PARTITION_TREE_COLS];
-		bool		nulls[PG_PARTITION_TREE_COLS];
+		Datum		values[PG_PARTITION_TREE_COLS] = {0};
+		bool		nulls[PG_PARTITION_TREE_COLS] = {0};
 		HeapTuple	tuple;
 		Oid			parentid = InvalidOid;
 		Oid			relid = list_nth_oid(partitions, funcctx->call_cntr);
@@ -126,8 +126,6 @@ pg_partition_tree(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(nulls, 0, sizeof(nulls));
-		MemSet(values, 0, sizeof(values));
 
 		/* relid */
 		values[0] = ObjectIdGetDatum(relid);
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 893690dad5..0a6369fdba 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -488,13 +488,10 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 	{
 		LocalPgBackendStatus *local_beentry;
 		PgBackendStatus *beentry;
-		Datum		values[PG_STAT_GET_PROGRESS_COLS];
-		bool		nulls[PG_STAT_GET_PROGRESS_COLS];
+		Datum		values[PG_STAT_GET_PROGRESS_COLS] = {0};
+		bool		nulls[PG_STAT_GET_PROGRESS_COLS] = {0};
 		int			i;
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
 
 		if (!local_beentry)
@@ -551,17 +548,14 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 	for (curr_backend = 1; curr_backend <= num_backends; curr_backend++)
 	{
 		/* for each row */
-		Datum		values[PG_STAT_GET_ACTIVITY_COLS];
-		bool		nulls[PG_STAT_GET_ACTIVITY_COLS];
+		Datum		values[PG_STAT_GET_ACTIVITY_COLS] = {0};
+		bool		nulls[PG_STAT_GET_ACTIVITY_COLS] = {0};
 		LocalPgBackendStatus *local_beentry;
 		PgBackendStatus *beentry;
 		PGPROC	   *proc;
 		const char *wait_event_type = NULL;
 		const char *wait_event = NULL;
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		/* Get the next one in the list */
 		local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
 		if (!local_beentry)
@@ -1747,15 +1741,11 @@ pg_stat_get_wal(PG_FUNCTION_ARGS)
 {
 #define PG_STAT_GET_WAL_COLS	9
 	TupleDesc	tupdesc;
-	Datum		values[PG_STAT_GET_WAL_COLS];
-	bool		nulls[PG_STAT_GET_WAL_COLS];
+	Datum		values[PG_STAT_GET_WAL_COLS] = {0};
+	bool		nulls[PG_STAT_GET_WAL_COLS] = {0};
 	char		buf[256];
 	PgStat_WalStats *wal_stats;
 
-	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* Initialise attributes information in the tuple descriptor */
 	tupdesc = CreateTemplateTupleDesc(PG_STAT_GET_WAL_COLS);
 	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "wal_records",
@@ -1827,7 +1817,7 @@ pg_stat_get_slru(PG_FUNCTION_ARGS)
 	{
 		/* for each row */
 		Datum		values[PG_STAT_GET_SLRU_COLS];
-		bool		nulls[PG_STAT_GET_SLRU_COLS];
+		bool		nulls[PG_STAT_GET_SLRU_COLS] = {0};
 		PgStat_SLRUStats stat;
 		const char *name;
 
@@ -1837,8 +1827,6 @@ pg_stat_get_slru(PG_FUNCTION_ARGS)
 			break;
 
 		stat = stats[i];
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
 
 		values[0] = PointerGetDatum(cstring_to_text(name));
 		values[1] = Int64GetDatum(stat.blocks_zeroed);
@@ -2201,14 +2189,10 @@ Datum
 pg_stat_get_archiver(PG_FUNCTION_ARGS)
 {
 	TupleDesc	tupdesc;
-	Datum		values[7];
-	bool		nulls[7];
+	Datum		values[7] = {0};
+	bool		nulls[7] = {0};
 	PgStat_ArchiverStats *archiver_stats;
 
-	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* Initialise attributes information in the tuple descriptor */
 	tupdesc = CreateTemplateTupleDesc(7);
 	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "archived_count",
@@ -2274,15 +2258,11 @@ pg_stat_get_replication_slot(PG_FUNCTION_ARGS)
 	text	   *slotname_text = PG_GETARG_TEXT_P(0);
 	NameData	slotname;
 	TupleDesc	tupdesc;
-	Datum		values[PG_STAT_GET_REPLICATION_SLOT_COLS];
-	bool		nulls[PG_STAT_GET_REPLICATION_SLOT_COLS];
+	Datum		values[PG_STAT_GET_REPLICATION_SLOT_COLS] = {0};
+	bool		nulls[PG_STAT_GET_REPLICATION_SLOT_COLS] = {0};
 	PgStat_StatReplSlotEntry *slotent;
 	PgStat_StatReplSlotEntry allzero;
 
-	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* Initialise attributes information in the tuple descriptor */
 	tupdesc = CreateTemplateTupleDesc(PG_STAT_GET_REPLICATION_SLOT_COLS);
 	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "slot_name",
@@ -2348,8 +2328,8 @@ pg_stat_get_subscription_stats(PG_FUNCTION_ARGS)
 #define PG_STAT_GET_SUBSCRIPTION_STATS_COLS	4
 	Oid			subid = PG_GETARG_OID(0);
 	TupleDesc	tupdesc;
-	Datum		values[PG_STAT_GET_SUBSCRIPTION_STATS_COLS];
-	bool		nulls[PG_STAT_GET_SUBSCRIPTION_STATS_COLS];
+	Datum		values[PG_STAT_GET_SUBSCRIPTION_STATS_COLS] = {0};
+	bool		nulls[PG_STAT_GET_SUBSCRIPTION_STATS_COLS] = {0};
 	PgStat_StatSubEntry *subentry;
 	PgStat_StatSubEntry allzero;
 
@@ -2368,10 +2348,6 @@ pg_stat_get_subscription_stats(PG_FUNCTION_ARGS)
 					   TIMESTAMPTZOID, -1, 0);
 	BlessTupleDesc(tupdesc);
 
-	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	if (!subentry)
 	{
 		/* If the subscription is not found, initialise its stats */
diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c
index fa1f589fad..6f99b5b243 100644
--- a/src/backend/utils/adt/selfuncs.c
+++ b/src/backend/utils/adt/selfuncs.c
@@ -6642,10 +6642,10 @@ btcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 			   double *indexPages)
 {
 	IndexOptInfo *index = path->indexinfo;
-	GenericCosts costs;
+	GenericCosts costs = {0};
 	Oid			relid;
 	AttrNumber	colnum;
-	VariableStatData vardata;
+	VariableStatData vardata = {0};
 	double		numIndexTuples;
 	Cost		descentCost;
 	List	   *indexBoundQuals;
@@ -6797,7 +6797,6 @@ btcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	/*
 	 * Now do generic index cost estimation.
 	 */
-	MemSet(&costs, 0, sizeof(costs));
 	costs.numIndexTuples = numIndexTuples;
 
 	genericcostestimate(root, path, loop_count, &costs);
@@ -6842,8 +6841,6 @@ btcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	 * ordering, but don't negate it entirely.  Before 8.0 we divided the
 	 * correlation by the number of columns, but that seems too strong.)
 	 */
-	MemSet(&vardata, 0, sizeof(vardata));
-
 	if (index->indexkeys[0] != 0)
 	{
 		/* Simple variable --- look to stats for the underlying table */
@@ -6947,9 +6944,7 @@ hashcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 				 Selectivity *indexSelectivity, double *indexCorrelation,
 				 double *indexPages)
 {
-	GenericCosts costs;
-
-	MemSet(&costs, 0, sizeof(costs));
+	GenericCosts costs = {0};
 
 	genericcostestimate(root, path, loop_count, &costs);
 
@@ -6992,11 +6987,9 @@ gistcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 				 double *indexPages)
 {
 	IndexOptInfo *index = path->indexinfo;
-	GenericCosts costs;
+	GenericCosts costs = {0};
 	Cost		descentCost;
 
-	MemSet(&costs, 0, sizeof(costs));
-
 	genericcostestimate(root, path, loop_count, &costs);
 
 	/*
@@ -7049,11 +7042,9 @@ spgcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 				double *indexPages)
 {
 	IndexOptInfo *index = path->indexinfo;
-	GenericCosts costs;
+	GenericCosts costs = {0};
 	Cost		descentCost;
 
-	MemSet(&costs, 0, sizeof(costs));
-
 	genericcostestimate(root, path, loop_count, &costs);
 
 	/*
diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index f70f829d83..0a17f45e92 100644
--- a/src/backend/utils/adt/timestamp.c
+++ b/src/backend/utils/adt/timestamp.c
@@ -2403,7 +2403,7 @@ interval_cmp_value(const Interval *interval)
 }
 
 static int
-interval_cmp_internal(Interval *interval1, Interval *interval2)
+interval_cmp_internal(const Interval *interval1, const Interval *interval2)
 {
 	INT128		span1 = interval_cmp_value(interval1);
 	INT128		span2 = interval_cmp_value(interval2);
@@ -5777,7 +5777,7 @@ generate_series_timestamp(PG_FUNCTION_ARGS)
 		Timestamp	finish = PG_GETARG_TIMESTAMP(1);
 		Interval   *step = PG_GETARG_INTERVAL_P(2);
 		MemoryContext oldcontext;
-		Interval	interval_zero;
+		Interval	interval_zero = {0};
 
 		/* create a function context for cross-call persistence */
 		funcctx = SRF_FIRSTCALL_INIT();
@@ -5800,7 +5800,6 @@ generate_series_timestamp(PG_FUNCTION_ARGS)
 		fctx->step = *step;
 
 		/* Determine sign of the interval */
-		MemSet(&interval_zero, 0, sizeof(Interval));
 		fctx->step_sign = interval_cmp_internal(&fctx->step, &interval_zero);
 
 		if (fctx->step_sign == 0)
@@ -5857,7 +5856,7 @@ generate_series_timestamptz(PG_FUNCTION_ARGS)
 		TimestampTz finish = PG_GETARG_TIMESTAMPTZ(1);
 		Interval   *step = PG_GETARG_INTERVAL_P(2);
 		MemoryContext oldcontext;
-		Interval	interval_zero;
+		Interval	interval_zero = {0};
 
 		/* create a function context for cross-call persistence */
 		funcctx = SRF_FIRSTCALL_INIT();
@@ -5880,7 +5879,6 @@ generate_series_timestamptz(PG_FUNCTION_ARGS)
 		fctx->step = *step;
 
 		/* Determine sign of the interval */
-		MemSet(&interval_zero, 0, sizeof(Interval));
 		fctx->step_sign = interval_cmp_internal(&fctx->step, &interval_zero);
 
 		if (fctx->step_sign == 0)
diff --git a/src/backend/utils/adt/tsrank.c b/src/backend/utils/adt/tsrank.c
index 3858fc5928..7d78219b62 100644
--- a/src/backend/utils/adt/tsrank.c
+++ b/src/backend/utils/adt/tsrank.c
@@ -853,7 +853,7 @@ calc_rank_cd(const float4 *arrdata, TSVector txt, TSQuery query, int method)
 	int			len,
 				i,
 				doclen = 0;
-	CoverExt	ext;
+	CoverExt	ext = {0};
 	double		Wdoc = 0.0;
 	double		invws[lengthof(weights)];
 	double		SumDist = 0.0,
@@ -883,7 +883,6 @@ calc_rank_cd(const float4 *arrdata, TSVector txt, TSQuery query, int method)
 		return 0.0;
 	}
 
-	MemSet(&ext, 0, sizeof(CoverExt));
 	while (Cover(doc, doclen, &qr, &ext))
 	{
 		double		Cpos = 0.0;
diff --git a/src/backend/utils/cache/relfilenumbermap.c b/src/backend/utils/cache/relfilenumbermap.c
index c4245d5ccd..ada0efa8f2 100644
--- a/src/backend/utils/cache/relfilenumbermap.c
+++ b/src/backend/utils/cache/relfilenumbermap.c
@@ -143,7 +143,7 @@ RelidByRelfilenumber(Oid reltablespace, RelFileNumber relfilenumber)
 	SysScanDesc scandesc;
 	Relation	relation;
 	HeapTuple	ntp;
-	ScanKeyData skey[2];
+	ScanKeyData skey[2] = {0};
 	Oid			relid;
 
 	if (RelfilenumberMapHash == NULL)
@@ -153,7 +153,6 @@ RelidByRelfilenumber(Oid reltablespace, RelFileNumber relfilenumber)
 	if (reltablespace == MyDatabaseTableSpace)
 		reltablespace = 0;
 
-	MemSet(&key, 0, sizeof(key));
 	key.reltablespace = reltablespace;
 	key.relfilenumber = relfilenumber;
 
diff --git a/src/backend/utils/cache/ts_cache.c b/src/backend/utils/cache/ts_cache.c
index 24808dfbb1..70e88fd228 100644
--- a/src/backend/utils/cache/ts_cache.c
+++ b/src/backend/utils/cache/ts_cache.c
@@ -414,7 +414,7 @@ lookup_ts_config_cache(Oid cfgId)
 		ScanKeyData mapskey;
 		SysScanDesc mapscan;
 		HeapTuple	maptup;
-		ListDictionary maplists[MAXTOKENTYPE + 1];
+		ListDictionary maplists[MAXTOKENTYPE + 1] = {0};
 		Oid			mapdicts[MAXDICTSPERTT];
 		int			maxtokentype;
 		int			ndicts;
@@ -468,7 +468,6 @@ lookup_ts_config_cache(Oid cfgId)
 		 * see the entries in maptokentype order, and in mapseqno order for
 		 * each token type, even though we didn't explicitly ask for that.
 		 */
-		MemSet(maplists, 0, sizeof(maplists));
 		maxtokentype = 0;
 		ndicts = 0;
 
diff --git a/src/backend/utils/misc/ps_status.c b/src/backend/utils/misc/ps_status.c
index ec314c03f5..ca05b180c9 100644
--- a/src/backend/utils/misc/ps_status.c
+++ b/src/backend/utils/misc/ps_status.c
@@ -393,7 +393,7 @@ set_ps_display(const char *activity)
 #ifdef PS_USE_CLOBBER_ARGV
 	/* pad unused memory; need only clobber remainder of old status string */
 	if (last_status_len > ps_buffer_cur_len)
-		MemSet(ps_buffer + ps_buffer_cur_len, PS_PADDING,
+		memset(ps_buffer + ps_buffer_cur_len, PS_PADDING,
 			   last_status_len - ps_buffer_cur_len);
 	last_status_len = ps_buffer_cur_len;
 #endif							/* PS_USE_CLOBBER_ARGV */
diff --git a/src/backend/utils/misc/timeout.c b/src/backend/utils/misc/timeout.c
index 6f5e08bc30..284b9153ea 100644
--- a/src/backend/utils/misc/timeout.c
+++ b/src/backend/utils/misc/timeout.c
@@ -211,13 +211,11 @@ schedule_alarm(TimestampTz now)
 {
 	if (num_active_timeouts > 0)
 	{
-		struct itimerval timeval;
+		struct itimerval timeval = {0};
 		TimestampTz nearest_timeout;
 		long		secs;
 		int			usecs;
 
-		MemSet(&timeval, 0, sizeof(struct itimerval));
-
 		/*
 		 * If we think there's a signal pending, but current time is more than
 		 * 10ms past when the signal was due, then assume that the timeout
diff --git a/src/backend/utils/mmgr/portalmem.c b/src/backend/utils/mmgr/portalmem.c
index d549f66d4a..3a161bdb88 100644
--- a/src/backend/utils/mmgr/portalmem.c
+++ b/src/backend/utils/mmgr/portalmem.c
@@ -1146,14 +1146,12 @@ pg_cursor(PG_FUNCTION_ARGS)
 	{
 		Portal		portal = hentry->portal;
 		Datum		values[6];
-		bool		nulls[6];
+		bool		nulls[6] = {0};
 
 		/* report only "visible" entries */
 		if (!portal->visible)
 			continue;
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		values[0] = CStringGetTextDatum(portal->name);
 		values[1] = CStringGetTextDatum(portal->sourceText);
 		values[2] = BoolGetDatum(portal->cursorOptions & CURSOR_OPT_HOLD);
diff --git a/src/bin/pg_basebackup/pg_basebackup.c b/src/bin/pg_basebackup/pg_basebackup.c
index 4445a86aee..79b23fa7d7 100644
--- a/src/bin/pg_basebackup/pg_basebackup.c
+++ b/src/bin/pg_basebackup/pg_basebackup.c
@@ -447,7 +447,7 @@ reached_end_position(XLogRecPtr segendpos, uint32 timeline,
 	{
 #ifndef WIN32
 		fd_set		fds;
-		struct timeval tv;
+		struct timeval tv = {0};
 		int			r;
 
 		/*
@@ -457,16 +457,13 @@ reached_end_position(XLogRecPtr segendpos, uint32 timeline,
 		FD_ZERO(&fds);
 		FD_SET(bgpipe[0], &fds);
 
-		MemSet(&tv, 0, sizeof(tv));
-
 		r = select(bgpipe[0] + 1, &fds, NULL, NULL, &tv);
 		if (r == 1)
 		{
-			char		xlogend[64];
+			char		xlogend[64] = {0};
 			uint32		hi,
 						lo;
 
-			MemSet(xlogend, 0, sizeof(xlogend));
 			r = read(bgpipe[0], xlogend, sizeof(xlogend) - 1);
 			if (r < 0)
 				pg_fatal("could not read from ready pipe: %m");
@@ -528,11 +525,10 @@ typedef struct
 static int
 LogStreamerMain(logstreamer_param *param)
 {
-	StreamCtl	stream;
+	StreamCtl	stream = {0};
 
 	in_log_streamer = true;
 
-	MemSet(&stream, 0, sizeof(stream));
 	stream.startpos = param->startptr;
 	stream.timeline = param->timeline;
 	stream.sysidentifier = param->sysidentifier;
@@ -1952,7 +1948,6 @@ BaseBackup(char *compression_algorithm, char *compression_detail,
 	else
 		starttli = latesttli;
 	PQclear(res);
-	MemSet(xlogend, 0, sizeof(xlogend));
 
 	if (verbose && includewal != NO_WAL)
 		pg_log_info("write-ahead log start point: %s on timeline %u",
diff --git a/src/bin/pg_basebackup/pg_receivewal.c b/src/bin/pg_basebackup/pg_receivewal.c
index ea3902c971..f064cff4ab 100644
--- a/src/bin/pg_basebackup/pg_receivewal.c
+++ b/src/bin/pg_basebackup/pg_receivewal.c
@@ -564,11 +564,9 @@ StreamLog(void)
 {
 	XLogRecPtr	serverpos;
 	TimeLineID	servertli;
-	StreamCtl	stream;
+	StreamCtl	stream = {0};
 	char	   *sysidentifier;
 
-	MemSet(&stream, 0, sizeof(stream));
-
 	/*
 	 * Connect in replication mode to the server
 	 */
diff --git a/src/bin/pg_basebackup/walmethods.c b/src/bin/pg_basebackup/walmethods.c
index ef4c11277a..e90aa0ba37 100644
--- a/src/bin/pg_basebackup/walmethods.c
+++ b/src/bin/pg_basebackup/walmethods.c
@@ -1111,9 +1111,8 @@ tar_close(Walfile f, WalCloseMethod method)
 	padding = tarPaddingBytesRequired(filesize);
 	if (padding)
 	{
-		char		zerobuf[TAR_BLOCK_SIZE];
+		char		zerobuf[TAR_BLOCK_SIZE] = {0};
 
-		MemSet(zerobuf, 0, padding);
 		if (tar_write(f, zerobuf, padding) != padding)
 			return -1;
 	}
@@ -1222,7 +1221,7 @@ tar_existsfile(const char *pathname)
 static bool
 tar_finish(void)
 {
-	char		zerobuf[1024];
+	char		zerobuf[1024] = {0};
 
 	tar_clear_error();
 
@@ -1233,7 +1232,6 @@ tar_finish(void)
 	}
 
 	/* A tarfile always ends with two empty blocks */
-	MemSet(zerobuf, 0, sizeof(zerobuf));
 	if (tar_data->compression_algorithm == PG_COMPRESSION_NONE)
 	{
 		errno = 0;
diff --git a/src/common/ip.c b/src/common/ip.c
index cd73d49679..267103efb9 100644
--- a/src/common/ip.c
+++ b/src/common/ip.c
@@ -165,14 +165,12 @@ static int
 getaddrinfo_unix(const char *path, const struct addrinfo *hintsp,
 				 struct addrinfo **result)
 {
-	struct addrinfo hints;
+	struct addrinfo hints = {0};
 	struct addrinfo *aip;
 	struct sockaddr_un *unp;
 
 	*result = NULL;
 
-	MemSet(&hints, 0, sizeof(hints));
-
 	if (strlen(path) >= sizeof(unp->sun_path))
 		return EAI_FAIL;
 
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index dc49387d6c..0362500386 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -2325,7 +2325,7 @@ keep_going:						/* We will come back to here until there is
 	if (conn->try_next_host)
 	{
 		pg_conn_host *ch;
-		struct addrinfo hint;
+		struct addrinfo hint = {0};
 		int			thisport;
 		int			ret;
 		char		portstr[MAXPGPATH];
@@ -2364,7 +2364,6 @@ keep_going:						/* We will come back to here until there is
 		ch = &conn->connhost[conn->whichhost];
 
 		/* Initialize hint structure */
-		MemSet(&hint, 0, sizeof(hint));
 		hint.ai_socktype = SOCK_STREAM;
 		conn->addrlist_family = hint.ai_family = AF_UNSPEC;
 
diff --git a/src/pl/plperl/plperl.c b/src/pl/plperl/plperl.c
index edb93ec1c4..6272e093c5 100644
--- a/src/pl/plperl/plperl.c
+++ b/src/pl/plperl/plperl.c
@@ -1841,10 +1841,9 @@ plperl_call_handler(PG_FUNCTION_ARGS)
 	Datum		retval = (Datum) 0;
 	plperl_call_data *volatile save_call_data = current_call_data;
 	plperl_interp_desc *volatile oldinterp = plperl_active_interp;
-	plperl_call_data this_call_data;
+	plperl_call_data this_call_data = {0};
 
 	/* Initialize current-call status record */
-	MemSet(&this_call_data, 0, sizeof(this_call_data));
 	this_call_data.fcinfo = fcinfo;
 
 	PG_TRY();
@@ -1882,16 +1881,13 @@ plperl_inline_handler(PG_FUNCTION_ARGS)
 {
 	LOCAL_FCINFO(fake_fcinfo, 0);
 	InlineCodeBlock *codeblock = (InlineCodeBlock *) PG_GETARG_POINTER(0);
-	FmgrInfo	flinfo;
-	plperl_proc_desc desc;
+	FmgrInfo	flinfo = {0};
+	plperl_proc_desc desc = {0};
 	plperl_call_data *volatile save_call_data = current_call_data;
 	plperl_interp_desc *volatile oldinterp = plperl_active_interp;
-	plperl_call_data this_call_data;
+	plperl_call_data this_call_data = {0};
 	ErrorContextCallback pl_error_context;
 
-	/* Initialize current-call status record */
-	MemSet(&this_call_data, 0, sizeof(this_call_data));
-
 	/* Set up a callback for error reporting */
 	pl_error_context.callback = plperl_inline_callback;
 	pl_error_context.previous = error_context_stack;
@@ -1904,8 +1900,6 @@ plperl_inline_handler(PG_FUNCTION_ARGS)
 	 * with no arguments passed, and a result type of VOID.
 	 */
 	MemSet(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
-	MemSet(&flinfo, 0, sizeof(flinfo));
-	MemSet(&desc, 0, sizeof(desc));
 	fake_fcinfo->flinfo = &flinfo;
 	flinfo.fn_oid = InvalidOid;
 	flinfo.fn_mcxt = CurrentMemoryContext;
diff --git a/src/pl/plpgsql/src/pl_handler.c b/src/pl/plpgsql/src/pl_handler.c
index 190d286f1c..1f8c9edfa8 100644
--- a/src/pl/plpgsql/src/pl_handler.c
+++ b/src/pl/plpgsql/src/pl_handler.c
@@ -317,7 +317,7 @@ plpgsql_inline_handler(PG_FUNCTION_ARGS)
 	LOCAL_FCINFO(fake_fcinfo, 0);
 	InlineCodeBlock *codeblock = castNode(InlineCodeBlock, DatumGetPointer(PG_GETARG_DATUM(0)));
 	PLpgSQL_function *func;
-	FmgrInfo	flinfo;
+	FmgrInfo	flinfo = {0};
 	EState	   *simple_eval_estate;
 	ResourceOwner simple_eval_resowner;
 	Datum		retval;
@@ -341,7 +341,6 @@ plpgsql_inline_handler(PG_FUNCTION_ARGS)
 	 * with no arguments passed.
 	 */
 	MemSet(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
-	MemSet(&flinfo, 0, sizeof(flinfo));
 	fake_fcinfo->flinfo = &flinfo;
 	flinfo.fn_oid = InvalidOid;
 	flinfo.fn_mcxt = CurrentMemoryContext;
@@ -502,10 +501,10 @@ plpgsql_validator(PG_FUNCTION_ARGS)
 	if (check_function_bodies)
 	{
 		LOCAL_FCINFO(fake_fcinfo, 0);
-		FmgrInfo	flinfo;
+		FmgrInfo	flinfo = {0};
 		int			rc;
-		TriggerData trigdata;
-		EventTriggerData etrigdata;
+		TriggerData trigdata = {0};
+		EventTriggerData etrigdata = {0};
 
 		/*
 		 * Connect to SPI manager (is this needed for compilation?)
@@ -518,19 +517,16 @@ plpgsql_validator(PG_FUNCTION_ARGS)
 		 * plpgsql_compile().
 		 */
 		MemSet(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
-		MemSet(&flinfo, 0, sizeof(flinfo));
 		fake_fcinfo->flinfo = &flinfo;
 		flinfo.fn_oid = funcoid;
 		flinfo.fn_mcxt = CurrentMemoryContext;
 		if (is_dml_trigger)
 		{
-			MemSet(&trigdata, 0, sizeof(trigdata));
 			trigdata.type = T_TriggerData;
 			fake_fcinfo->context = (Node *) &trigdata;
 		}
 		else if (is_event_trigger)
 		{
-			MemSet(&etrigdata, 0, sizeof(etrigdata));
 			etrigdata.type = T_EventTriggerData;
 			fake_fcinfo->context = (Node *) &etrigdata;
 		}
diff --git a/src/pl/plpython/plpy_main.c b/src/pl/plpython/plpy_main.c
index 0bce106495..1df2dd536c 100644
--- a/src/pl/plpython/plpy_main.c
+++ b/src/pl/plpython/plpy_main.c
@@ -266,8 +266,8 @@ plpython3_inline_handler(PG_FUNCTION_ARGS)
 {
 	LOCAL_FCINFO(fake_fcinfo, 0);
 	InlineCodeBlock *codeblock = (InlineCodeBlock *) DatumGetPointer(PG_GETARG_DATUM(0));
-	FmgrInfo	flinfo;
-	PLyProcedure proc;
+	FmgrInfo	flinfo = {0};
+	PLyProcedure proc = {0};
 	PLyExecutionContext *exec_ctx;
 	ErrorContextCallback plerrcontext;
 
@@ -278,12 +278,10 @@ plpython3_inline_handler(PG_FUNCTION_ARGS)
 		elog(ERROR, "SPI_connect failed");
 
 	MemSet(fcinfo, 0, SizeForFunctionCallInfo(0));
-	MemSet(&flinfo, 0, sizeof(flinfo));
 	fake_fcinfo->flinfo = &flinfo;
 	flinfo.fn_oid = InvalidOid;
 	flinfo.fn_mcxt = CurrentMemoryContext;
 
-	MemSet(&proc, 0, sizeof(PLyProcedure));
 	proc.mcxt = AllocSetContextCreate(TopMemoryContext,
 									  "__plpython_inline_block",
 									  ALLOCSET_DEFAULT_SIZES);
diff --git a/src/port/snprintf.c b/src/port/snprintf.c
index abb1c59770..d4cf368075 100644
--- a/src/port/snprintf.c
+++ b/src/port/snprintf.c
@@ -756,12 +756,10 @@ find_arguments(const char *format, va_list args,
 	int			longflag;
 	int			fmtpos;
 	int			i;
-	int			last_dollar;
-	PrintfArgType argtypes[PG_NL_ARGMAX + 1];
 
 	/* Initialize to "no dollar arguments known" */
-	last_dollar = 0;
-	MemSet(argtypes, 0, sizeof(argtypes));
+	int			last_dollar = 0;
+	PrintfArgType argtypes[PG_NL_ARGMAX + 1] = {0};
 
 	/*
 	 * This loop must accept the same format strings as the one in dopr().
diff --git a/src/test/modules/test_predtest/test_predtest.c b/src/test/modules/test_predtest/test_predtest.c
index 3b19e0eadc..2ce88cb624 100644
--- a/src/test/modules/test_predtest/test_predtest.c
+++ b/src/test/modules/test_predtest/test_predtest.c
@@ -50,7 +50,7 @@ test_predtest(PG_FUNCTION_ARGS)
 				strong_refuted_by,
 				weak_refuted_by;
 	Datum		values[8];
-	bool		nulls[8];
+	bool		nulls[8] = {0};
 	int			i;
 
 	/* We use SPI to parse, plan, and execute the test query */
@@ -204,7 +204,6 @@ test_predtest(PG_FUNCTION_ARGS)
 					   "w_r_holds", BOOLOID, -1, 0);
 	tupdesc = BlessTupleDesc(tupdesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = BoolGetDatum(strong_implied_by);
 	values[1] = BoolGetDatum(weak_implied_by);
 	values[2] = BoolGetDatum(strong_refuted_by);
diff --git a/src/test/regress/regress.c b/src/test/regress/regress.c
index ba3532a51e..b88d70b6fc 100644
--- a/src/test/regress/regress.c
+++ b/src/test/regress/regress.c
@@ -1110,7 +1110,7 @@ test_enc_conversion(PG_FUNCTION_ARGS)
 	int			convertedbytes;
 	int			dstlen;
 	Datum		values[2];
-	bool		nulls[2];
+	bool		nulls[2] = {0};
 	HeapTuple	tuple;
 
 	if (src_encoding < 0)
@@ -1199,7 +1199,6 @@ test_enc_conversion(PG_FUNCTION_ARGS)
 		pfree(dst);
 	}
 
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = Int32GetDatum(convertedbytes);
 	values[1] = PointerGetDatum(retval);
 	tuple = heap_form_tuple(tupdesc, values, nulls);
diff --git a/src/tools/msvc/MSBuildProject.pm b/src/tools/msvc/MSBuildProject.pm
index f24d9e5348..5e2a300127 100644
--- a/src/tools/msvc/MSBuildProject.pm
+++ b/src/tools/msvc/MSBuildProject.pm
@@ -331,7 +331,7 @@ sub WriteItemDefinitionGroup
       <ObjectFileName>.\\$cfgname\\$self->{name}\\</ObjectFileName>
       <ProgramDataBaseFileName>.\\$cfgname\\$self->{name}\\</ProgramDataBaseFileName>
       <BrowseInformation>false</BrowseInformation>
-      <WarningLevel>Level3</WarningLevel>
+      <WarningLevel>Level4</WarningLevel>
       <SuppressStartupBanner>true</SuppressStartupBanner>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <CompileAs>Default</CompileAs>

diff --git a/contrib/amcheck/verify_heapam.c b/contrib/amcheck/verify_heapam.c
index e488f5e234..4cd4354278 100644
--- a/contrib/amcheck/verify_heapam.c
+++ b/contrib/amcheck/verify_heapam.c
@@ -554,17 +554,15 @@ report_corruption_internal(Tuplestorestate *tupstore, TupleDesc tupdesc,
 						   BlockNumber blkno, OffsetNumber offnum,
 						   AttrNumber attnum, char *msg)
 {
-	Datum		values[HEAPCHECK_RELATION_COLS];
-	bool		nulls[HEAPCHECK_RELATION_COLS];
+	Datum		values[HEAPCHECK_RELATION_COLS] = {0};
+	bool		nulls[HEAPCHECK_RELATION_COLS] = {0};
 	HeapTuple	tuple;
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = Int64GetDatum(blkno);
 	values[1] = Int32GetDatum(offnum);
 	values[2] = Int32GetDatum(attnum);
-	nulls[2] = (attnum < 0);
 	values[3] = CStringGetTextDatum(msg);
+	nulls[2] = (attnum < 0);
 
 	/*
 	 * In principle, there is nothing to prevent a scan over a large, highly
diff --git a/contrib/bloom/blcost.c b/contrib/bloom/blcost.c
index d42e4e9628..d4b1c76303 100644
--- a/contrib/bloom/blcost.c
+++ b/contrib/bloom/blcost.c
@@ -26,9 +26,7 @@ blcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 			   double *indexPages)
 {
 	IndexOptInfo *index = path->indexinfo;
-	GenericCosts costs;
-
-	MemSet(&costs, 0, sizeof(costs));
+	GenericCosts costs = {0};
 
 	/* We have to visit all index tuples anyway */
 	costs.numIndexTuples = index->tuples;
diff --git a/contrib/pageinspect/brinfuncs.c b/contrib/pageinspect/brinfuncs.c
index 879276e6de..f4c959ecab 100644
--- a/contrib/pageinspect/brinfuncs.c
+++ b/contrib/pageinspect/brinfuncs.c
@@ -202,7 +202,7 @@ brin_page_items(PG_FUNCTION_ARGS)
 	for (;;)
 	{
 		Datum		values[7];
-		bool		nulls[7];
+		bool		nulls[7] = {0};
 
 		/*
 		 * This loop is called once for every attribute of every tuple in the
@@ -230,8 +230,6 @@ brin_page_items(PG_FUNCTION_ARGS)
 		else
 			attno++;
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		if (unusedItem)
 		{
 			values[0] = UInt16GetDatum(offset);
@@ -334,7 +332,7 @@ brin_metapage_info(PG_FUNCTION_ARGS)
 	BrinMetaPageData *meta;
 	TupleDesc	tupdesc;
 	Datum		values[4];
-	bool		nulls[4];
+	bool		nulls[4] = {0};
 	HeapTuple	htup;
 
 	if (!superuser())
@@ -354,7 +352,6 @@ brin_metapage_info(PG_FUNCTION_ARGS)
 
 	/* Extract values from the metapage */
 	meta = (BrinMetaPageData *) PageGetContents(page);
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = CStringGetTextDatum(psprintf("0x%08X", meta->brinMagic));
 	values[1] = Int32GetDatum(meta->brinVersion);
 	values[2] = Int32GetDatum(meta->pagesPerRange);
diff --git a/contrib/pageinspect/hashfuncs.c b/contrib/pageinspect/hashfuncs.c
index 5287dbe1a3..81815392d7 100644
--- a/contrib/pageinspect/hashfuncs.c
+++ b/contrib/pageinspect/hashfuncs.c
@@ -238,7 +238,7 @@ hash_page_stats(PG_FUNCTION_ARGS)
 	Page		page;
 	int			j;
 	Datum		values[9];
-	bool		nulls[9];
+	bool		nulls[9] = {0};
 	HashPageStat stat;
 	HeapTuple	tuple;
 	TupleDesc	tupleDesc;
@@ -261,8 +261,6 @@ hash_page_stats(PG_FUNCTION_ARGS)
 		elog(ERROR, "return type must be a row type");
 	tupleDesc = BlessTupleDesc(tupleDesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
-
 	j = 0;
 	values[j++] = Int32GetDatum(stat.live_items);
 	values[j++] = Int32GetDatum(stat.dead_items);
@@ -303,7 +301,7 @@ hash_page_items(PG_FUNCTION_ARGS)
 	Page		page;
 	Datum		result;
 	Datum		values[3];
-	bool		nulls[3];
+	bool		nulls[3] = {0};
 	uint32		hashkey;
 	HeapTuple	tuple;
 	FuncCallContext *fctx;
@@ -361,8 +359,6 @@ hash_page_items(PG_FUNCTION_ARGS)
 
 		itup = (IndexTuple) PageGetItem(uargs->page, id);
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		j = 0;
 		values[j++] = Int32GetDatum((int32) uargs->offset);
 		values[j++] = PointerGetDatum(&itup->t_tid);
@@ -409,7 +405,7 @@ hash_bitmap_info(PG_FUNCTION_ARGS)
 	int			i,
 				j;
 	Datum		values[3];
-	bool		nulls[3];
+	bool		nulls[3] = {0};
 	uint32	   *freep;
 
 	if (!superuser())
@@ -495,8 +491,6 @@ hash_bitmap_info(PG_FUNCTION_ARGS)
 		elog(ERROR, "return type must be a row type");
 	tupleDesc = BlessTupleDesc(tupleDesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
-
 	j = 0;
 	values[j++] = Int64GetDatum((int64) bitmapblkno);
 	values[j++] = Int32GetDatum(bitmapbit);
@@ -526,7 +520,7 @@ hash_metapage_info(PG_FUNCTION_ARGS)
 	int			i,
 				j;
 	Datum		values[16];
-	bool		nulls[16];
+	bool		nulls[16] = {0};
 	Datum		spares[HASH_MAX_SPLITPOINTS];
 	Datum		mapp[HASH_MAX_BITMAPS];
 
@@ -544,8 +538,6 @@ hash_metapage_info(PG_FUNCTION_ARGS)
 
 	metad = HashPageGetMeta(page);
 
-	MemSet(nulls, 0, sizeof(nulls));
-
 	j = 0;
 	values[j++] = Int64GetDatum((int64) metad->hashm_magic);
 	values[j++] = Int64GetDatum((int64) metad->hashm_version);
diff --git a/contrib/pageinspect/heapfuncs.c b/contrib/pageinspect/heapfuncs.c
index a654234c6b..952f5ed57e 100644
--- a/contrib/pageinspect/heapfuncs.c
+++ b/contrib/pageinspect/heapfuncs.c
@@ -181,13 +181,11 @@ heap_page_items(PG_FUNCTION_ARGS)
 		Datum		result;
 		ItemId		id;
 		Datum		values[14];
-		bool		nulls[14];
+		bool		nulls[14] = {0};
 		uint16		lp_offset;
 		uint16		lp_flags;
 		uint16		lp_len;
 
-		memset(nulls, 0, sizeof(nulls));
-
 		/* Extract information from the line pointer */
 
 		id = PageGetItemId(page, inter_call_data->offset);
@@ -507,8 +505,8 @@ Datum
 heap_tuple_infomask_flags(PG_FUNCTION_ARGS)
 {
 #define HEAP_TUPLE_INFOMASK_COLS 2
-	Datum		values[HEAP_TUPLE_INFOMASK_COLS];
-	bool		nulls[HEAP_TUPLE_INFOMASK_COLS];
+	Datum		values[HEAP_TUPLE_INFOMASK_COLS] = {0};
+	bool		nulls[HEAP_TUPLE_INFOMASK_COLS] = {0};
 	uint16		t_infomask = PG_GETARG_INT16(0);
 	uint16		t_infomask2 = PG_GETARG_INT16(1);
 	int			cnt = 0;
@@ -530,10 +528,6 @@ heap_tuple_infomask_flags(PG_FUNCTION_ARGS)
 	bitcnt = pg_popcount((const char *) &t_infomask, sizeof(uint16)) +
 		pg_popcount((const char *) &t_infomask2, sizeof(uint16));
 
-	/* Initialize values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* If no flags, return a set of empty arrays */
 	if (bitcnt <= 0)
 	{
diff --git a/contrib/pg_prewarm/autoprewarm.c b/contrib/pg_prewarm/autoprewarm.c
index 13eee4a137..ee20e9b085 100644
--- a/contrib/pg_prewarm/autoprewarm.c
+++ b/contrib/pg_prewarm/autoprewarm.c
@@ -814,12 +814,11 @@ apw_detach_shmem(int code, Datum arg)
 static void
 apw_start_leader_worker(void)
 {
-	BackgroundWorker worker;
+	BackgroundWorker worker = {0};
 	BackgroundWorkerHandle *handle;
 	BgwHandleStatus status;
 	pid_t		pid;
 
-	MemSet(&worker, 0, sizeof(BackgroundWorker));
 	worker.bgw_flags = BGWORKER_SHMEM_ACCESS;
 	worker.bgw_start_time = BgWorkerStart_ConsistentState;
 	strcpy(worker.bgw_library_name, "pg_prewarm");
@@ -856,10 +855,9 @@ apw_start_leader_worker(void)
 static void
 apw_start_database_worker(void)
 {
-	BackgroundWorker worker;
+	BackgroundWorker worker = {0};
 	BackgroundWorkerHandle *handle;
 
-	MemSet(&worker, 0, sizeof(BackgroundWorker));
 	worker.bgw_flags =
 		BGWORKER_SHMEM_ACCESS | BGWORKER_BACKEND_DATABASE_CONNECTION;
 	worker.bgw_start_time = BgWorkerStart_ConsistentState;
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index 4acfddcdb8..b4d4231dc6 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -1854,8 +1854,8 @@ pg_stat_statements_info(PG_FUNCTION_ARGS)
 {
 	pgssGlobalStats stats;
 	TupleDesc	tupdesc;
-	Datum		values[PG_STAT_STATEMENTS_INFO_COLS];
-	bool		nulls[PG_STAT_STATEMENTS_INFO_COLS];
+	Datum		values[PG_STAT_STATEMENTS_INFO_COLS] = {0};
+	bool		nulls[PG_STAT_STATEMENTS_INFO_COLS] = {0};
 
 	if (!pgss || !pgss_hash)
 		ereport(ERROR,
@@ -1866,9 +1866,6 @@ pg_stat_statements_info(PG_FUNCTION_ARGS)
 	if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
 		elog(ERROR, "return type must be a row type");
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* Read global statistics for pg_stat_statements */
 	{
 		volatile pgssSharedState *s = (volatile pgssSharedState *) pgss;
diff --git a/contrib/pg_trgm/trgm_regexp.c b/contrib/pg_trgm/trgm_regexp.c
index 58d32ba946..a155d4c13d 100644
--- a/contrib/pg_trgm/trgm_regexp.c
+++ b/contrib/pg_trgm/trgm_regexp.c
@@ -905,7 +905,7 @@ static void
 transformGraph(TrgmNFA *trgmNFA)
 {
 	HASHCTL		hashCtl;
-	TrgmStateKey initkey;
+	TrgmStateKey initkey = {0};
 	TrgmState  *initstate;
 	ListCell   *lc;
 
@@ -926,7 +926,6 @@ transformGraph(TrgmNFA *trgmNFA)
 	trgmNFA->nstates = 0;
 
 	/* Create initial state: ambiguous prefix, NFA's initial state */
-	MemSet(&initkey, 0, sizeof(initkey));
 	initkey.prefix.colors[0] = COLOR_UNKNOWN;
 	initkey.prefix.colors[1] = COLOR_UNKNOWN;
 	initkey.nstate = pg_reg_getinitialstate(trgmNFA->regex);
@@ -1014,22 +1013,19 @@ processState(TrgmNFA *trgmNFA, TrgmState *state)
  *
  * Note that we don't generate any actual arcs here.  addArcs will do that
  * later, after we have identified all the enter keys for this state.
+ *
+ * Ensure any pad bytes in destKey are zero, since it may get used as a
+ * hashtable key by getState.
  */
 static void
 addKey(TrgmNFA *trgmNFA, TrgmState *state, TrgmStateKey *key)
 {
 	regex_arc_t *arcs;
-	TrgmStateKey destKey;
+	TrgmStateKey destKey = {0};
 	ListCell   *cell;
 	int			i,
 				arcsCount;
 
-	/*
-	 * Ensure any pad bytes in destKey are zero, since it may get used as a
-	 * hashtable key by getState.
-	 */
-	MemSet(&destKey, 0, sizeof(destKey));
-
 	/*
 	 * Compare key to each existing enter key of the state to check for
 	 * redundancy.  We can drop either old key(s) or the new key if we find
@@ -1195,22 +1191,19 @@ addKeyToQueue(TrgmNFA *trgmNFA, TrgmStateKey *key)
 
 /*
  * Add outgoing arcs from given state, whose enter keys are all now known.
+ *
+ * Ensure any pad bytes in destKey are zero, since it may get used as a
+ * hashtable key by getState.
  */
 static void
 addArcs(TrgmNFA *trgmNFA, TrgmState *state)
 {
-	TrgmStateKey destKey;
+	TrgmStateKey destKey = {0};
 	ListCell   *cell;
 	regex_arc_t *arcs;
 	int			arcsCount,
 				i;
 
-	/*
-	 * Ensure any pad bytes in destKey are zero, since it may get used as a
-	 * hashtable key by getState.
-	 */
-	MemSet(&destKey, 0, sizeof(destKey));
-
 	/*
 	 * Iterate over enter keys associated with this expanded-graph state. This
 	 * includes both the state's own stateKey, and any enter keys we added to
diff --git a/contrib/pg_visibility/pg_visibility.c b/contrib/pg_visibility/pg_visibility.c
index 4e2e9ea9bb..a95f73ec79 100644
--- a/contrib/pg_visibility/pg_visibility.c
+++ b/contrib/pg_visibility/pg_visibility.c
@@ -75,7 +75,7 @@ pg_visibility_map(PG_FUNCTION_ARGS)
 	Buffer		vmbuffer = InvalidBuffer;
 	TupleDesc	tupdesc;
 	Datum		values[2];
-	bool		nulls[2];
+	bool		nulls[2] = {0};
 
 	rel = relation_open(relid, AccessShareLock);
 
@@ -88,7 +88,6 @@ pg_visibility_map(PG_FUNCTION_ARGS)
 				 errmsg("invalid block number")));
 
 	tupdesc = pg_visibility_tupdesc(false, false);
-	MemSet(nulls, 0, sizeof(nulls));
 
 	mapbits = (int32) visibilitymap_get_status(rel, blkno, &vmbuffer);
 	if (vmbuffer != InvalidBuffer)
@@ -117,7 +116,7 @@ pg_visibility(PG_FUNCTION_ARGS)
 	Page		page;
 	TupleDesc	tupdesc;
 	Datum		values[3];
-	bool		nulls[3];
+	bool		nulls[3] = {0};
 
 	rel = relation_open(relid, AccessShareLock);
 
@@ -130,7 +129,6 @@ pg_visibility(PG_FUNCTION_ARGS)
 				 errmsg("invalid block number")));
 
 	tupdesc = pg_visibility_tupdesc(false, true);
-	MemSet(nulls, 0, sizeof(nulls));
 
 	mapbits = (int32) visibilitymap_get_status(rel, blkno, &vmbuffer);
 	if (vmbuffer != InvalidBuffer)
@@ -188,10 +186,9 @@ pg_visibility_map_rel(PG_FUNCTION_ARGS)
 	if (info->next < info->count)
 	{
 		Datum		values[3];
-		bool		nulls[3];
+		bool		nulls[3] = {0};
 		HeapTuple	tuple;
 
-		MemSet(nulls, 0, sizeof(nulls));
 		values[0] = Int64GetDatum(info->next);
 		values[1] = BoolGetDatum((info->bits[info->next] & (1 << 0)) != 0);
 		values[2] = BoolGetDatum((info->bits[info->next] & (1 << 1)) != 0);
@@ -233,10 +230,9 @@ pg_visibility_rel(PG_FUNCTION_ARGS)
 	if (info->next < info->count)
 	{
 		Datum		values[4];
-		bool		nulls[4];
+		bool		nulls[4] = {0};
 		HeapTuple	tuple;
 
-		MemSet(nulls, 0, sizeof(nulls));
 		values[0] = Int64GetDatum(info->next);
 		values[1] = BoolGetDatum((info->bits[info->next] & (1 << 0)) != 0);
 		values[2] = BoolGetDatum((info->bits[info->next] & (1 << 1)) != 0);
@@ -266,7 +262,7 @@ pg_visibility_map_summary(PG_FUNCTION_ARGS)
 	int64		all_frozen = 0;
 	TupleDesc	tupdesc;
 	Datum		values[2];
-	bool		nulls[2];
+	bool		nulls[2] = {0};
 
 	rel = relation_open(relid, AccessShareLock);
 
@@ -300,7 +296,6 @@ pg_visibility_map_summary(PG_FUNCTION_ARGS)
 	TupleDescInitEntry(tupdesc, (AttrNumber) 2, "all_frozen", INT8OID, -1, 0);
 	tupdesc = BlessTupleDesc(tupdesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = Int64GetDatum(all_visible);
 	values[1] = Int64GetDatum(all_frozen);
 
diff --git a/contrib/pg_walinspect/pg_walinspect.c b/contrib/pg_walinspect/pg_walinspect.c
index a082dfb331..9081787634 100644
--- a/contrib/pg_walinspect/pg_walinspect.c
+++ b/contrib/pg_walinspect/pg_walinspect.c
@@ -229,8 +229,8 @@ pg_get_wal_record_info(PG_FUNCTION_ARGS)
 {
 #define PG_GET_WAL_RECORD_INFO_COLS 11
 	Datum		result;
-	Datum		values[PG_GET_WAL_RECORD_INFO_COLS];
-	bool		nulls[PG_GET_WAL_RECORD_INFO_COLS];
+	Datum		values[PG_GET_WAL_RECORD_INFO_COLS] = {0};
+	bool		nulls[PG_GET_WAL_RECORD_INFO_COLS] = {0};
 	XLogRecPtr	lsn;
 	XLogRecPtr	curr_lsn;
 	XLogRecPtr	first_record;
@@ -266,9 +266,6 @@ pg_get_wal_record_info(PG_FUNCTION_ARGS)
 				 errmsg("could not read WAL at %X/%X",
 						LSN_FORMAT_ARGS(first_record))));
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	GetWALRecordInfo(xlogreader, first_record, values, nulls,
 					 PG_GET_WAL_RECORD_INFO_COLS);
 
@@ -334,8 +331,8 @@ GetWALRecordsInfo(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
 	XLogRecPtr	first_record;
 	XLogReaderState *xlogreader;
 	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
-	Datum		values[PG_GET_WAL_RECORDS_INFO_COLS];
-	bool		nulls[PG_GET_WAL_RECORDS_INFO_COLS];
+	Datum		values[PG_GET_WAL_RECORDS_INFO_COLS] = {0};
+	bool		nulls[PG_GET_WAL_RECORDS_INFO_COLS] = {0};
 
 	SetSingleFuncCall(fcinfo, 0);
 
@@ -343,9 +340,6 @@ GetWALRecordsInfo(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
 
 	Assert(xlogreader);
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	while (ReadNextXLogRecord(xlogreader, first_record) &&
 		   xlogreader->EndRecPtr <= end_lsn)
 	{
@@ -556,17 +550,15 @@ GetWalStats(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
 #define PG_GET_WAL_STATS_COLS 9
 	XLogRecPtr	first_record;
 	XLogReaderState *xlogreader;
-	XLogStats	stats;
+	XLogStats	stats = {0};
 	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
-	Datum		values[PG_GET_WAL_STATS_COLS];
-	bool		nulls[PG_GET_WAL_STATS_COLS];
+	Datum		values[PG_GET_WAL_STATS_COLS] = {0};
+	bool		nulls[PG_GET_WAL_STATS_COLS] = {0};
 
 	SetSingleFuncCall(fcinfo, 0);
 
 	xlogreader = InitXLogReaderState(start_lsn, &first_record);
 
-	MemSet(&stats, 0, sizeof(stats));
-
 	while (ReadNextXLogRecord(xlogreader, first_record) &&
 		   xlogreader->EndRecPtr <= end_lsn)
 	{
@@ -578,9 +570,6 @@ GetWalStats(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
 	pfree(xlogreader->private_data);
 	XLogReaderFree(xlogreader);
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	GetXLogSummaryStats(&stats, rsinfo, values, nulls,
 						PG_GET_WAL_STATS_COLS,
 						stats_per_record);
diff --git a/contrib/pgstattuple/pgstatindex.c b/contrib/pgstattuple/pgstatindex.c
index e1048e47ff..d69ac1c93d 100644
--- a/contrib/pgstattuple/pgstatindex.c
+++ b/contrib/pgstattuple/pgstatindex.c
@@ -575,7 +575,7 @@ pgstathashindex(PG_FUNCTION_ARGS)
 	HeapTuple	tuple;
 	TupleDesc	tupleDesc;
 	Datum		values[8];
-	bool		nulls[8];
+	bool		nulls[8] = {0};
 	Buffer		metabuf;
 	HashMetaPage metap;
 	float8		free_percent;
@@ -697,7 +697,6 @@ pgstathashindex(PG_FUNCTION_ARGS)
 	/*
 	 * Build and return the tuple
 	 */
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = Int32GetDatum(stats.version);
 	values[1] = Int64GetDatum((int64) stats.bucket_pages);
 	values[2] = Int64GetDatum((int64) stats.overflow_pages);
diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c
index cffb6f8310..939d114f02 100644
--- a/contrib/postgres_fdw/connection.c
+++ b/contrib/postgres_fdw/connection.c
@@ -1678,8 +1678,8 @@ postgres_fdw_get_connections(PG_FUNCTION_ARGS)
 	while ((entry = (ConnCacheEntry *) hash_seq_search(&scan)))
 	{
 		ForeignServer *server;
-		Datum		values[POSTGRES_FDW_GET_CONNECTIONS_COLS];
-		bool		nulls[POSTGRES_FDW_GET_CONNECTIONS_COLS];
+		Datum		values[POSTGRES_FDW_GET_CONNECTIONS_COLS] = {0};
+		bool		nulls[POSTGRES_FDW_GET_CONNECTIONS_COLS] = {0};
 
 		/* We only look for open remote connections */
 		if (!entry->conn)
@@ -1687,9 +1687,6 @@ postgres_fdw_get_connections(PG_FUNCTION_ARGS)
 
 		server = GetForeignServerExtended(entry->serverid, FSV_MISSING_OK);
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		/*
 		 * The foreign server may have been dropped in current explicit
 		 * transaction. It is not possible to drop the server from another
diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c
index 955a428e3d..cfac539008 100644
--- a/contrib/postgres_fdw/postgres_fdw.c
+++ b/contrib/postgres_fdw/postgres_fdw.c
@@ -3307,7 +3307,7 @@ estimate_path_cost_size(PlannerInfo *root,
 		{
 			RelOptInfo *outerrel = fpinfo->outerrel;
 			PgFdwRelationInfo *ofpinfo;
-			AggClauseCosts aggcosts;
+			AggClauseCosts aggcosts = {0};
 			double		input_rows;
 			int			numGroupCols;
 			double		numGroups = 1;
@@ -3331,7 +3331,6 @@ estimate_path_cost_size(PlannerInfo *root,
 			input_rows = ofpinfo->rows;
 
 			/* Collect statistics about aggregates for estimating costs. */
-			MemSet(&aggcosts, 0, sizeof(AggClauseCosts));
 			if (root->parse->hasAggs)
 			{
 				get_agg_clause_costs(root, AGGSPLIT_SIMPLE, &aggcosts);
diff --git a/contrib/tablefunc/tablefunc.c b/contrib/tablefunc/tablefunc.c
index e308228bde..6452111e19 100644
--- a/contrib/tablefunc/tablefunc.c
+++ b/contrib/tablefunc/tablefunc.c
@@ -127,9 +127,8 @@ typedef struct crosstab_cat_desc
 
 #define crosstab_HashTableLookup(HASHTAB, CATNAME, CATDESC) \
 do { \
-	crosstab_HashEnt *hentry; char key[MAX_CATNAME_LEN]; \
+	crosstab_HashEnt *hentry; char key[MAX_CATNAME_LEN] = {0}; \
 	\
-	MemSet(key, 0, MAX_CATNAME_LEN); \
 	snprintf(key, MAX_CATNAME_LEN - 1, "%s", CATNAME); \
 	hentry = (crosstab_HashEnt*) hash_search(HASHTAB, \
 										 key, HASH_FIND, NULL); \
@@ -141,9 +140,8 @@ do { \
 
 #define crosstab_HashTableInsert(HASHTAB, CATDESC) \
 do { \
-	crosstab_HashEnt *hentry; bool found; char key[MAX_CATNAME_LEN]; \
+	crosstab_HashEnt *hentry; bool found; char key[MAX_CATNAME_LEN] = {0}; \
 	\
-	MemSet(key, 0, MAX_CATNAME_LEN); \
 	snprintf(key, MAX_CATNAME_LEN - 1, "%s", CATDESC->catname); \
 	hentry = (crosstab_HashEnt*) hash_search(HASHTAB, \
 										 key, HASH_ENTER, &found); \
diff --git a/src/backend/access/nbtree/nbtxlog.c b/src/backend/access/nbtree/nbtxlog.c
index ad489e33b3..14fe2d76c4 100644
--- a/src/backend/access/nbtree/nbtxlog.c
+++ b/src/backend/access/nbtree/nbtxlog.c
@@ -717,7 +717,7 @@ btree_xlog_mark_page_halfdead(uint8 info, XLogReaderState *record)
 	Buffer		buffer;
 	Page		page;
 	BTPageOpaque pageop;
-	IndexTupleData trunctuple;
+	IndexTupleData trunctuple = {0};
 
 	/*
 	 * In normal operation, we would lock all the pages this WAL record
@@ -780,7 +780,6 @@ btree_xlog_mark_page_halfdead(uint8 info, XLogReaderState *record)
 	 * Construct a dummy high key item that points to top parent page (value
 	 * is InvalidBlockNumber when the top parent page is the leaf page itself)
 	 */
-	MemSet(&trunctuple, 0, sizeof(IndexTupleData));
 	trunctuple.t_info = sizeof(IndexTupleData);
 	BTreeTupleSetTopParent(&trunctuple, xlrec->topparent);
 
@@ -898,7 +897,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record)
 		 * we'll delete in the subtree undergoing deletion.
 		 */
 		Buffer		leafbuf;
-		IndexTupleData trunctuple;
+		IndexTupleData trunctuple = {0};
 
 		Assert(!isleaf);
 
@@ -915,7 +914,6 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record)
 		pageop->btpo_cycleid = 0;
 
 		/* Add a dummy hikey item */
-		MemSet(&trunctuple, 0, sizeof(IndexTupleData));
 		trunctuple.t_info = sizeof(IndexTupleData);
 		BTreeTupleSetTopParent(&trunctuple, xlrec->leaftopparent);
 
diff --git a/src/backend/access/transam/twophase.c b/src/backend/access/transam/twophase.c
index 41b31c5c6f..dd330ce260 100644
--- a/src/backend/access/transam/twophase.c
+++ b/src/backend/access/transam/twophase.c
@@ -781,7 +781,7 @@ pg_prepared_xact(PG_FUNCTION_ARGS)
 		GlobalTransaction gxact = &status->array[status->currIdx++];
 		PGPROC	   *proc = &ProcGlobal->allProcs[gxact->pgprocno];
 		Datum		values[5];
-		bool		nulls[5];
+		bool		nulls[5] = {0};
 		HeapTuple	tuple;
 		Datum		result;
 
@@ -791,9 +791,6 @@ pg_prepared_xact(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		values[0] = TransactionIdGetDatum(proc->xid);
 		values[1] = CStringGetTextDatum(gxact->gid);
 		values[2] = TimestampTzGetDatum(gxact->prepared_at);
diff --git a/src/backend/access/transam/xlogfuncs.c b/src/backend/access/transam/xlogfuncs.c
index 02bd919ff6..ed79e3d9a3 100644
--- a/src/backend/access/transam/xlogfuncs.c
+++ b/src/backend/access/transam/xlogfuncs.c
@@ -107,7 +107,7 @@ pg_backup_stop(PG_FUNCTION_ARGS)
 #define PG_STOP_BACKUP_V2_COLS 3
 	TupleDesc	tupdesc;
 	Datum		values[PG_STOP_BACKUP_V2_COLS];
-	bool		nulls[PG_STOP_BACKUP_V2_COLS];
+	bool		nulls[PG_STOP_BACKUP_V2_COLS] = {0};
 
 	bool		waitforarchive = PG_GETARG_BOOL(0);
 	XLogRecPtr	stoppoint;
@@ -117,9 +117,6 @@ pg_backup_stop(PG_FUNCTION_ARGS)
 	if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
 		elog(ERROR, "return type must be a row type");
 
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	if (status != SESSION_BACKUP_RUNNING)
 		ereport(ERROR,
 				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
diff --git a/src/backend/catalog/aclchk.c b/src/backend/catalog/aclchk.c
index 5f1726c095..0bd4557050 100644
--- a/src/backend/catalog/aclchk.c
+++ b/src/backend/catalog/aclchk.c
@@ -1188,9 +1188,6 @@ SetDefaultACL(InternalDefaultACL *iacls)
 	Acl		   *old_acl;
 	Acl		   *new_acl;
 	HeapTuple	newtuple;
-	Datum		values[Natts_pg_default_acl];
-	bool		nulls[Natts_pg_default_acl];
-	bool		replaces[Natts_pg_default_acl];
 	int			noldmembers;
 	int			nnewmembers;
 	Oid		   *oldmembers;
@@ -1341,13 +1338,10 @@ SetDefaultACL(InternalDefaultACL *iacls)
 	}
 	else
 	{
+		Datum		values[Natts_pg_default_acl] = {0};
+		bool		nulls[Natts_pg_default_acl] = {0};
 		Oid			defAclOid;
 
-		/* Prepare to insert or update pg_default_acl entry */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		if (isNew)
 		{
 			/* insert new entry */
@@ -1364,6 +1358,8 @@ SetDefaultACL(InternalDefaultACL *iacls)
 		}
 		else
 		{
+			bool		replaces[Natts_pg_default_acl] = {0};
+
 			defAclOid = ((Form_pg_default_acl) GETSTRUCT(tuple))->oid;
 
 			/* update existing entry */
@@ -1662,9 +1658,8 @@ ExecGrant_Attribute(InternalGrant *istmt, Oid relOid, const char *relname,
 	AclMode		avail_goptions;
 	bool		need_update;
 	HeapTuple	newtuple;
-	Datum		values[Natts_pg_attribute];
-	bool		nulls[Natts_pg_attribute];
-	bool		replaces[Natts_pg_attribute];
+	Datum		values[Natts_pg_attribute] = {0};
+	bool		nulls[Natts_pg_attribute] = {0};
 	int			noldmembers;
 	int			nnewmembers;
 	Oid		   *oldmembers;
@@ -1745,9 +1740,6 @@ ExecGrant_Attribute(InternalGrant *istmt, Oid relOid, const char *relname,
 	nnewmembers = aclmembers(new_acl, &newmembers);
 
 	/* finished building new ACL value, now insert it */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, false, sizeof(nulls));
-	MemSet(replaces, false, sizeof(replaces));
 
 	/*
 	 * If the updated ACL is empty, we can set attacl to null, and maybe even
@@ -1766,10 +1758,12 @@ ExecGrant_Attribute(InternalGrant *istmt, Oid relOid, const char *relname,
 		nulls[Anum_pg_attribute_attacl - 1] = true;
 		need_update = !isNull;
 	}
-	replaces[Anum_pg_attribute_attacl - 1] = true;
 
 	if (need_update)
 	{
+		bool		replaces[Natts_pg_attribute] = {0};
+
+		replaces[Anum_pg_attribute_attacl - 1] = true;
 		newtuple = heap_modify_tuple(attr_tuple, RelationGetDescr(attRelation),
 									 values, nulls, replaces);
 
@@ -1975,9 +1969,9 @@ ExecGrant_Relation(InternalGrant *istmt)
 			Acl		   *new_acl;
 			Oid			grantorId;
 			HeapTuple	newtuple;
-			Datum		values[Natts_pg_class];
-			bool		nulls[Natts_pg_class];
-			bool		replaces[Natts_pg_class];
+			Datum		values[Natts_pg_class] = {0};
+			bool		nulls[Natts_pg_class] = {0};
+			bool		replaces[Natts_pg_class] = {0};
 			int			nnewmembers;
 			Oid		   *newmembers;
 			ObjectType	objtype;
@@ -2027,10 +2021,6 @@ ExecGrant_Relation(InternalGrant *istmt)
 			nnewmembers = aclmembers(new_acl, &newmembers);
 
 			/* finished building new ACL value, now insert it */
-			MemSet(values, 0, sizeof(values));
-			MemSet(nulls, false, sizeof(nulls));
-			MemSet(replaces, false, sizeof(replaces));
-
 			replaces[Anum_pg_class_relacl - 1] = true;
 			values[Anum_pg_class_relacl - 1] = PointerGetDatum(new_acl);
 
@@ -2129,6 +2119,9 @@ ExecGrant_Relation(InternalGrant *istmt)
 static void
 ExecGrant_Database(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_database] = {0};
+	bool		nulls[Natts_pg_database] = {0};
+	bool		replaces[Natts_pg_database] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -2150,9 +2143,6 @@ ExecGrant_Database(InternalGrant *istmt)
 		Oid			grantorId;
 		Oid			ownerId;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_database];
-		bool		nulls[Natts_pg_database];
-		bool		replaces[Natts_pg_database];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2217,10 +2207,6 @@ ExecGrant_Database(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_database_datacl - 1] = true;
 		values[Anum_pg_database_datacl - 1] = PointerGetDatum(new_acl);
 
@@ -2249,6 +2235,9 @@ ExecGrant_Database(InternalGrant *istmt)
 static void
 ExecGrant_Fdw(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_foreign_data_wrapper] = {0};
+	bool		nulls[Natts_pg_foreign_data_wrapper] = {0};
+	bool		replaces[Natts_pg_foreign_data_wrapper] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -2271,9 +2260,6 @@ ExecGrant_Fdw(InternalGrant *istmt)
 		Oid			ownerId;
 		HeapTuple	tuple;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_foreign_data_wrapper];
-		bool		nulls[Natts_pg_foreign_data_wrapper];
-		bool		replaces[Natts_pg_foreign_data_wrapper];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2339,10 +2325,6 @@ ExecGrant_Fdw(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_foreign_data_wrapper_fdwacl - 1] = true;
 		values[Anum_pg_foreign_data_wrapper_fdwacl - 1] = PointerGetDatum(new_acl);
 
@@ -2376,6 +2358,9 @@ ExecGrant_Fdw(InternalGrant *istmt)
 static void
 ExecGrant_ForeignServer(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_foreign_server] = {0};
+	bool		nulls[Natts_pg_foreign_server] = {0};
+	bool		replaces[Natts_pg_foreign_server] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -2398,9 +2383,6 @@ ExecGrant_ForeignServer(InternalGrant *istmt)
 		Oid			ownerId;
 		HeapTuple	tuple;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_foreign_server];
-		bool		nulls[Natts_pg_foreign_server];
-		bool		replaces[Natts_pg_foreign_server];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2465,10 +2447,6 @@ ExecGrant_ForeignServer(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_foreign_server_srvacl - 1] = true;
 		values[Anum_pg_foreign_server_srvacl - 1] = PointerGetDatum(new_acl);
 
@@ -2501,6 +2479,9 @@ ExecGrant_ForeignServer(InternalGrant *istmt)
 static void
 ExecGrant_Function(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_proc] = {0};
+	bool		nulls[Natts_pg_proc] = {0};
+	bool		replaces[Natts_pg_proc] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -2523,9 +2504,6 @@ ExecGrant_Function(InternalGrant *istmt)
 		Oid			ownerId;
 		HeapTuple	tuple;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_proc];
-		bool		nulls[Natts_pg_proc];
-		bool		replaces[Natts_pg_proc];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2589,10 +2567,6 @@ ExecGrant_Function(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_proc_proacl - 1] = true;
 		values[Anum_pg_proc_proacl - 1] = PointerGetDatum(new_acl);
 
@@ -2624,6 +2598,9 @@ ExecGrant_Function(InternalGrant *istmt)
 static void
 ExecGrant_Language(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_language] = {0};
+	bool		nulls[Natts_pg_language] = {0};
+	bool		replaces[Natts_pg_language] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -2646,9 +2623,6 @@ ExecGrant_Language(InternalGrant *istmt)
 		Oid			ownerId;
 		HeapTuple	tuple;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_language];
-		bool		nulls[Natts_pg_language];
-		bool		replaces[Natts_pg_language];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2720,10 +2694,6 @@ ExecGrant_Language(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_language_lanacl - 1] = true;
 		values[Anum_pg_language_lanacl - 1] = PointerGetDatum(new_acl);
 
@@ -2755,6 +2725,9 @@ ExecGrant_Language(InternalGrant *istmt)
 static void
 ExecGrant_Largeobject(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_largeobject_metadata] = {0};
+	bool		nulls[Natts_pg_largeobject_metadata] = {0};
+	bool		replaces[Natts_pg_largeobject_metadata] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -2778,9 +2751,6 @@ ExecGrant_Largeobject(InternalGrant *istmt)
 		Oid			grantorId;
 		Oid			ownerId;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_largeobject_metadata];
-		bool		nulls[Natts_pg_largeobject_metadata];
-		bool		replaces[Natts_pg_largeobject_metadata];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2858,10 +2828,6 @@ ExecGrant_Largeobject(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_largeobject_metadata_lomacl - 1] = true;
 		values[Anum_pg_largeobject_metadata_lomacl - 1]
 			= PointerGetDatum(new_acl);
@@ -2895,6 +2861,9 @@ ExecGrant_Largeobject(InternalGrant *istmt)
 static void
 ExecGrant_Namespace(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_namespace] = {0};
+	bool		nulls[Natts_pg_namespace] = {0};
+	bool		replaces[Natts_pg_namespace] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -2917,9 +2886,6 @@ ExecGrant_Namespace(InternalGrant *istmt)
 		Oid			ownerId;
 		HeapTuple	tuple;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_namespace];
-		bool		nulls[Natts_pg_namespace];
-		bool		replaces[Natts_pg_namespace];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -2984,10 +2950,6 @@ ExecGrant_Namespace(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_namespace_nspacl - 1] = true;
 		values[Anum_pg_namespace_nspacl - 1] = PointerGetDatum(new_acl);
 
@@ -3019,6 +2981,9 @@ ExecGrant_Namespace(InternalGrant *istmt)
 static void
 ExecGrant_Tablespace(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_tablespace] = {0};
+	bool		nulls[Natts_pg_tablespace] = {0};
+	bool		replaces[Natts_pg_tablespace] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -3040,9 +3005,6 @@ ExecGrant_Tablespace(InternalGrant *istmt)
 		Oid			grantorId;
 		Oid			ownerId;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_tablespace];
-		bool		nulls[Natts_pg_tablespace];
-		bool		replaces[Natts_pg_tablespace];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -3108,10 +3070,6 @@ ExecGrant_Tablespace(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_tablespace_spcacl - 1] = true;
 		values[Anum_pg_tablespace_spcacl - 1] = PointerGetDatum(new_acl);
 
@@ -3139,6 +3097,9 @@ ExecGrant_Tablespace(InternalGrant *istmt)
 static void
 ExecGrant_Type(InternalGrant *istmt)
 {
+	Datum		values[Natts_pg_type] = {0};
+	bool		nulls[Natts_pg_type] = {0};
+	bool		replaces[Natts_pg_type] = {0};
 	Relation	relation;
 	ListCell   *cell;
 
@@ -3160,9 +3121,6 @@ ExecGrant_Type(InternalGrant *istmt)
 		Oid			grantorId;
 		Oid			ownerId;
 		HeapTuple	newtuple;
-		Datum		values[Natts_pg_type];
-		bool		nulls[Natts_pg_type];
-		bool		replaces[Natts_pg_type];
 		int			noldmembers;
 		int			nnewmembers;
 		Oid		   *oldmembers;
@@ -3242,10 +3200,6 @@ ExecGrant_Type(InternalGrant *istmt)
 		nnewmembers = aclmembers(new_acl, &newmembers);
 
 		/* finished building new ACL value, now insert it */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-		MemSet(replaces, false, sizeof(replaces));
-
 		replaces[Anum_pg_type_typacl - 1] = true;
 		values[Anum_pg_type_typacl - 1] = PointerGetDatum(new_acl);
 
@@ -3384,13 +3338,9 @@ ExecGrant_Parameter(InternalGrant *istmt)
 		{
 			/* finished building new ACL value, now insert it */
 			HeapTuple	newtuple;
-			Datum		values[Natts_pg_parameter_acl];
-			bool		nulls[Natts_pg_parameter_acl];
-			bool		replaces[Natts_pg_parameter_acl];
-
-			MemSet(values, 0, sizeof(values));
-			MemSet(nulls, false, sizeof(nulls));
-			MemSet(replaces, false, sizeof(replaces));
+			Datum		values[Natts_pg_parameter_acl] = {0};
+			bool		nulls[Natts_pg_parameter_acl] = {0};
+			bool		replaces[Natts_pg_parameter_acl] = {0};
 
 			replaces[Anum_pg_parameter_acl_paracl - 1] = true;
 			values[Anum_pg_parameter_acl_paracl - 1] = PointerGetDatum(new_acl);
@@ -6419,16 +6369,12 @@ recordExtensionInitPrivWorker(Oid objoid, Oid classoid, int objsubid, Acl *new_a
 	/* If we find an entry, update it with the latest ACL. */
 	if (HeapTupleIsValid(oldtuple))
 	{
-		Datum		values[Natts_pg_init_privs];
-		bool		nulls[Natts_pg_init_privs];
-		bool		replace[Natts_pg_init_privs];
-
 		/* If we have a new ACL to set, then update the row with it. */
 		if (new_acl)
 		{
-			MemSet(values, 0, sizeof(values));
-			MemSet(nulls, false, sizeof(nulls));
-			MemSet(replace, false, sizeof(replace));
+			Datum		values[Natts_pg_init_privs] = {0};
+			bool		nulls[Natts_pg_init_privs] = {0};
+			bool		replace[Natts_pg_init_privs] = {0};
 
 			values[Anum_pg_init_privs_initprivs - 1] = PointerGetDatum(new_acl);
 			replace[Anum_pg_init_privs_initprivs - 1] = true;
@@ -6446,9 +6392,6 @@ recordExtensionInitPrivWorker(Oid objoid, Oid classoid, int objsubid, Acl *new_a
 	}
 	else
 	{
-		Datum		values[Natts_pg_init_privs];
-		bool		nulls[Natts_pg_init_privs];
-
 		/*
 		 * Only add a new entry if the new ACL is non-NULL.
 		 *
@@ -6457,9 +6400,10 @@ recordExtensionInitPrivWorker(Oid objoid, Oid classoid, int objsubid, Acl *new_a
 		 */
 		if (new_acl)
 		{
-			/* No entry found, so add it. */
-			MemSet(nulls, false, sizeof(nulls));
+			Datum		values[Natts_pg_init_privs] = {0};
+			bool		nulls[Natts_pg_init_privs] = {0};
 
+			/* No entry found, so add it. */
 			values[Anum_pg_init_privs_objoid - 1] = ObjectIdGetDatum(objoid);
 			values[Anum_pg_init_privs_classoid - 1] = ObjectIdGetDatum(classoid);
 			values[Anum_pg_init_privs_objsubid - 1] = Int32GetDatum(objsubid);
diff --git a/src/backend/catalog/dependency.c b/src/backend/catalog/dependency.c
index de10923391..5cbd72ce10 100644
--- a/src/backend/catalog/dependency.c
+++ b/src/backend/catalog/dependency.c
@@ -1635,12 +1635,11 @@ recordDependencyOnSingleRelExpr(const ObjectAddress *depender,
 								bool reverse_self)
 {
 	find_expr_references_context context;
-	RangeTblEntry rte;
+	RangeTblEntry rte = {0};
 
 	context.addrs = new_object_addresses();
 
 	/* We gin up a rather bogus rangetable list to handle Vars */
-	MemSet(&rte, 0, sizeof(rte));
 	rte.type = T_RangeTblEntry;
 	rte.rtekind = RTE_RELATION;
 	rte.relid = relId;
diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c
index e770ea6eb8..9b03579e6e 100644
--- a/src/backend/catalog/heap.c
+++ b/src/backend/catalog/heap.c
@@ -1709,15 +1709,11 @@ RemoveAttributeById(Oid relid, AttrNumber attnum)
 		/* clear the missing value if any */
 		if (attStruct->atthasmissing)
 		{
-			Datum		valuesAtt[Natts_pg_attribute];
-			bool		nullsAtt[Natts_pg_attribute];
-			bool		replacesAtt[Natts_pg_attribute];
+			Datum		valuesAtt[Natts_pg_attribute] = {0};
+			bool		nullsAtt[Natts_pg_attribute] = {0};
+			bool		replacesAtt[Natts_pg_attribute] = {0};
 
 			/* update the tuple - set atthasmissing and attmissingval */
-			MemSet(valuesAtt, 0, sizeof(valuesAtt));
-			MemSet(nullsAtt, false, sizeof(nullsAtt));
-			MemSet(replacesAtt, false, sizeof(replacesAtt));
-
 			valuesAtt[Anum_pg_attribute_atthasmissing - 1] =
 				BoolGetDatum(false);
 			replacesAtt[Anum_pg_attribute_atthasmissing - 1] = true;
@@ -2006,9 +2002,9 @@ RelationClearMissing(Relation rel)
 void
 SetAttrMissing(Oid relid, char *attname, char *value)
 {
-	Datum		valuesAtt[Natts_pg_attribute];
-	bool		nullsAtt[Natts_pg_attribute];
-	bool		replacesAtt[Natts_pg_attribute];
+	Datum		valuesAtt[Natts_pg_attribute] = {0};
+	bool		nullsAtt[Natts_pg_attribute] = {0};
+	bool		replacesAtt[Natts_pg_attribute] = {0};
 	Datum		missingval;
 	Form_pg_attribute attStruct;
 	Relation	attrrel,
@@ -2041,10 +2037,6 @@ SetAttrMissing(Oid relid, char *attname, char *value)
 								  Int32GetDatum(attStruct->atttypmod));
 
 	/* update the tuple - set atthasmissing and attmissingval */
-	MemSet(valuesAtt, 0, sizeof(valuesAtt));
-	MemSet(nullsAtt, false, sizeof(nullsAtt));
-	MemSet(replacesAtt, false, sizeof(replacesAtt));
-
 	valuesAtt[Anum_pg_attribute_atthasmissing - 1] = BoolGetDatum(true);
 	replacesAtt[Anum_pg_attribute_atthasmissing - 1] = true;
 	valuesAtt[Anum_pg_attribute_attmissingval - 1] = missingval;
@@ -3321,7 +3313,7 @@ StorePartitionKey(Relation rel,
 	Relation	pg_partitioned_table;
 	HeapTuple	tuple;
 	Datum		values[Natts_pg_partitioned_table];
-	bool		nulls[Natts_pg_partitioned_table];
+	bool		nulls[Natts_pg_partitioned_table] = {0};
 	ObjectAddress myself;
 	ObjectAddress referenced;
 	ObjectAddresses *addrs;
@@ -3347,8 +3339,6 @@ StorePartitionKey(Relation rel,
 
 	pg_partitioned_table = table_open(PartitionedRelationId, RowExclusiveLock);
 
-	MemSet(nulls, false, sizeof(nulls));
-
 	/* Only this can ever be NULL */
 	if (!partexprDatum)
 		nulls[Anum_pg_partitioned_table_partexprs - 1] = true;
diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c
index c5d463ac55..d7192f35e3 100644
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@@ -554,7 +554,7 @@ UpdateIndexRelation(Oid indexoid,
 	Datum		exprsDatum;
 	Datum		predDatum;
 	Datum		values[Natts_pg_index];
-	bool		nulls[Natts_pg_index];
+	bool		nulls[Natts_pg_index] = {0};
 	Relation	pg_index;
 	HeapTuple	tuple;
 	int			i;
@@ -608,8 +608,6 @@ UpdateIndexRelation(Oid indexoid,
 	/*
 	 * Build a pg_index tuple
 	 */
-	MemSet(nulls, false, sizeof(nulls));
-
 	values[Anum_pg_index_indexrelid - 1] = ObjectIdGetDatum(indexoid);
 	values[Anum_pg_index_indrelid - 1] = ObjectIdGetDatum(heapoid);
 	values[Anum_pg_index_indnatts - 1] = Int16GetDatum(indexInfo->ii_NumIndexAttrs);
diff --git a/src/backend/catalog/pg_attrdef.c b/src/backend/catalog/pg_attrdef.c
index c5d4a9912e..1a14093a9a 100644
--- a/src/backend/catalog/pg_attrdef.c
+++ b/src/backend/catalog/pg_attrdef.c
@@ -111,15 +111,12 @@ StoreAttrDefault(Relation rel, AttrNumber attnum,
 		Expr	   *expr2 = (Expr *) expr;
 		EState	   *estate = NULL;
 		ExprContext *econtext;
-		Datum		valuesAtt[Natts_pg_attribute];
-		bool		nullsAtt[Natts_pg_attribute];
-		bool		replacesAtt[Natts_pg_attribute];
+		Datum		valuesAtt[Natts_pg_attribute] = {0};
+		bool		nullsAtt[Natts_pg_attribute] = {0};
+		bool		replacesAtt[Natts_pg_attribute] = {0};
 		Datum		missingval = (Datum) 0;
 		bool		missingIsNull = true;
 
-		MemSet(valuesAtt, 0, sizeof(valuesAtt));
-		MemSet(nullsAtt, false, sizeof(nullsAtt));
-		MemSet(replacesAtt, false, sizeof(replacesAtt));
 		valuesAtt[Anum_pg_attribute_atthasdef - 1] = true;
 		replacesAtt[Anum_pg_attribute_atthasdef - 1] = true;
 
diff --git a/src/backend/catalog/pg_cast.c b/src/backend/catalog/pg_cast.c
index 4857f6468d..1812bb7fcc 100644
--- a/src/backend/catalog/pg_cast.c
+++ b/src/backend/catalog/pg_cast.c
@@ -47,7 +47,7 @@ CastCreate(Oid sourcetypeid, Oid targettypeid, Oid funcid, char castcontext,
 	HeapTuple	tuple;
 	Oid			castid;
 	Datum		values[Natts_pg_cast];
-	bool		nulls[Natts_pg_cast];
+	bool		nulls[Natts_pg_cast] = {0};
 	ObjectAddress myself,
 				referenced;
 	ObjectAddresses *addrs;
@@ -78,8 +78,6 @@ CastCreate(Oid sourcetypeid, Oid targettypeid, Oid funcid, char castcontext,
 	values[Anum_pg_cast_castcontext - 1] = CharGetDatum(castcontext);
 	values[Anum_pg_cast_castmethod - 1] = CharGetDatum(castmethod);
 
-	MemSet(nulls, false, sizeof(nulls));
-
 	tuple = heap_form_tuple(RelationGetDescr(relation), values, nulls);
 
 	CatalogTupleInsert(relation, tuple);
diff --git a/src/backend/catalog/pg_parameter_acl.c b/src/backend/catalog/pg_parameter_acl.c
index 2decee909b..0570e811d1 100644
--- a/src/backend/catalog/pg_parameter_acl.c
+++ b/src/backend/catalog/pg_parameter_acl.c
@@ -74,8 +74,8 @@ ParameterAclCreate(const char *parameter)
 	Relation	rel;
 	TupleDesc	tupDesc;
 	HeapTuple	tuple;
-	Datum		values[Natts_pg_parameter_acl];
-	bool		nulls[Natts_pg_parameter_acl];
+	Datum		values[Natts_pg_parameter_acl] = {0};
+	bool		nulls[Natts_pg_parameter_acl] = {0};
 
 	/*
 	 * To prevent cluttering pg_parameter_acl with useless entries, insist
@@ -98,8 +98,6 @@ ParameterAclCreate(const char *parameter)
 	 */
 	rel = table_open(ParameterAclRelationId, RowExclusiveLock);
 	tupDesc = RelationGetDescr(rel);
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, false, sizeof(nulls));
 	parameterId = GetNewOidWithIndex(rel,
 									 ParameterAclOidIndexId,
 									 Anum_pg_parameter_acl_oid);
diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index c365de3a72..4ff692cb5e 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -1162,15 +1162,12 @@ pg_get_publication_tables(PG_FUNCTION_ARGS)
 		HeapTuple	pubtuple = NULL;
 		HeapTuple	rettuple;
 		Oid			relid = list_nth_oid(tables, funcctx->call_cntr);
-		Datum		values[NUM_PUBLICATION_TABLES_ELEM];
-		bool		nulls[NUM_PUBLICATION_TABLES_ELEM];
+		Datum		values[NUM_PUBLICATION_TABLES_ELEM] = {0};
+		bool		nulls[NUM_PUBLICATION_TABLES_ELEM] = {0};
 
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(nulls, 0, sizeof(nulls));
-		MemSet(values, 0, sizeof(values));
-
 		publication = GetPublicationByName(pubname, false);
 
 		values[0] = ObjectIdGetDatum(relid);
diff --git a/src/backend/commands/copyfromparse.c b/src/backend/commands/copyfromparse.c
index 57813b3458..cef0f2c279 100644
--- a/src/backend/commands/copyfromparse.c
+++ b/src/backend/commands/copyfromparse.c
@@ -869,7 +869,7 @@ NextCopyFrom(CopyFromState cstate, ExprContext *econtext,
 
 	/* Initialize all values for row to NULL */
 	MemSet(values, 0, num_phys_attrs * sizeof(Datum));
-	MemSet(nulls, true, num_phys_attrs * sizeof(bool));
+	memset(nulls, true, num_phys_attrs * sizeof(bool));
 
 	if (!cstate->opts.binary)
 	{
diff --git a/src/backend/commands/dbcommands.c b/src/backend/commands/dbcommands.c
index 1901b434c5..099d369b2f 100644
--- a/src/backend/commands/dbcommands.c
+++ b/src/backend/commands/dbcommands.c
@@ -689,8 +689,8 @@ createdb(ParseState *pstate, const CreatedbStmt *stmt)
 	volatile Oid dst_deftablespace;
 	Relation	pg_database_rel;
 	HeapTuple	tuple;
-	Datum		new_record[Natts_pg_database];
-	bool		new_record_nulls[Natts_pg_database];
+	Datum		new_record[Natts_pg_database] = {0};
+	bool		new_record_nulls[Natts_pg_database] = {0};
 	Oid			dboid = InvalidOid;
 	Oid			datdba;
 	ListCell   *option;
@@ -1296,9 +1296,6 @@ createdb(ParseState *pstate, const CreatedbStmt *stmt)
 		   (dblocprovider != COLLPROVIDER_ICU && !dbiculocale));
 
 	/* Form tuple */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-
 	new_record[Anum_pg_database_oid - 1] = ObjectIdGetDatum(dboid);
 	new_record[Anum_pg_database_datname - 1] =
 		DirectFunctionCall1(namein, CStringGetDatum(dbname));
@@ -1822,9 +1819,6 @@ movedb(const char *dbname, const char *tblspcname)
 				newtuple;
 	Oid			src_tblspcoid,
 				dst_tblspcoid;
-	Datum		new_record[Natts_pg_database];
-	bool		new_record_nulls[Natts_pg_database];
-	bool		new_record_repl[Natts_pg_database];
 	ScanKeyData scankey;
 	SysScanDesc sysscan;
 	AclResult	aclresult;
@@ -2003,6 +1997,10 @@ movedb(const char *dbname, const char *tblspcname)
 	PG_ENSURE_ERROR_CLEANUP(movedb_failure_callback,
 							PointerGetDatum(&fparms));
 	{
+		Datum		new_record[Natts_pg_database] = {0};
+		bool		new_record_nulls[Natts_pg_database] = {0};
+		bool		new_record_repl[Natts_pg_database] = {0};
+
 		/*
 		 * Copy files from the old tablespace to the new one
 		 */
@@ -2042,10 +2040,6 @@ movedb(const char *dbname, const char *tblspcname)
 					(errcode(ERRCODE_UNDEFINED_DATABASE),
 					 errmsg("database \"%s\" does not exist", dbname)));
 
-		MemSet(new_record, 0, sizeof(new_record));
-		MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-		MemSet(new_record_repl, false, sizeof(new_record_repl));
-
 		new_record[Anum_pg_database_dattablespace - 1] = ObjectIdGetDatum(dst_tblspcoid);
 		new_record_repl[Anum_pg_database_dattablespace - 1] = true;
 
@@ -2194,9 +2188,9 @@ AlterDatabase(ParseState *pstate, AlterDatabaseStmt *stmt, bool isTopLevel)
 	DefElem    *dallowconnections = NULL;
 	DefElem    *dconnlimit = NULL;
 	DefElem    *dtablespace = NULL;
-	Datum		new_record[Natts_pg_database];
-	bool		new_record_nulls[Natts_pg_database];
-	bool		new_record_repl[Natts_pg_database];
+	Datum		new_record[Natts_pg_database] = {0};
+	bool		new_record_nulls[Natts_pg_database] = {0};
+	bool		new_record_repl[Natts_pg_database] = {0};
 
 	/* Extract options from the statement node tree */
 	foreach(option, stmt->options)
@@ -2305,10 +2299,6 @@ AlterDatabase(ParseState *pstate, AlterDatabaseStmt *stmt, bool isTopLevel)
 	/*
 	 * Build an updated tuple, perusing the information just obtained
 	 */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-	MemSet(new_record_repl, false, sizeof(new_record_repl));
-
 	if (distemplate)
 	{
 		new_record[Anum_pg_database_datistemplate - 1] = BoolGetDatum(dbistemplate);
@@ -2492,8 +2482,8 @@ AlterDatabaseOwner(const char *dbname, Oid newOwnerId)
 	if (datForm->datdba != newOwnerId)
 	{
 		Datum		repl_val[Natts_pg_database];
-		bool		repl_null[Natts_pg_database];
-		bool		repl_repl[Natts_pg_database];
+		bool		repl_null[Natts_pg_database] = {0};
+		bool		repl_repl[Natts_pg_database] = {0};
 		Acl		   *newAcl;
 		Datum		aclDatum;
 		bool		isNull;
@@ -2521,9 +2511,6 @@ AlterDatabaseOwner(const char *dbname, Oid newOwnerId)
 					(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
 					 errmsg("permission denied to change owner of database")));
 
-		memset(repl_null, false, sizeof(repl_null));
-		memset(repl_repl, false, sizeof(repl_repl));
-
 		repl_repl[Anum_pg_database_datdba - 1] = true;
 		repl_val[Anum_pg_database_datdba - 1] = ObjectIdGetDatum(newOwnerId);
 
diff --git a/src/backend/commands/event_trigger.c b/src/backend/commands/event_trigger.c
index f46f86474a..eef3e5d56e 100644
--- a/src/backend/commands/event_trigger.c
+++ b/src/backend/commands/event_trigger.c
@@ -1310,14 +1310,11 @@ pg_event_trigger_dropped_objects(PG_FUNCTION_ARGS)
 	{
 		SQLDropObject *obj;
 		int			i = 0;
-		Datum		values[12];
-		bool		nulls[12];
+		Datum		values[12] = {0};
+		bool		nulls[12] = {0};
 
 		obj = slist_container(SQLDropObject, next, iter.cur);
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		/* classid */
 		values[i++] = ObjectIdGetDatum(obj->address.classId);
 
@@ -1840,7 +1837,7 @@ pg_event_trigger_ddl_commands(PG_FUNCTION_ARGS)
 	{
 		CollectedCommand *cmd = lfirst(lc);
 		Datum		values[9];
-		bool		nulls[9];
+		bool		nulls[9] = {0};
 		ObjectAddress addr;
 		int			i = 0;
 
@@ -1858,8 +1855,6 @@ pg_event_trigger_ddl_commands(PG_FUNCTION_ARGS)
 			!OidIsValid(cmd->d.simple.address.objectId))
 			continue;
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		switch (cmd->type)
 		{
 			case SCT_Simple:
diff --git a/src/backend/commands/functioncmds.c b/src/backend/commands/functioncmds.c
index b016eecb2c..f51cfe6df1 100644
--- a/src/backend/commands/functioncmds.c
+++ b/src/backend/commands/functioncmds.c
@@ -1806,8 +1806,7 @@ CreateTransform(CreateTransformStmt *stmt)
 	AclResult	aclresult;
 	Form_pg_proc procstruct;
 	Datum		values[Natts_pg_transform];
-	bool		nulls[Natts_pg_transform];
-	bool		replaces[Natts_pg_transform];
+	bool		nulls[Natts_pg_transform] = {0};
 	Oid			transformid;
 	HeapTuple	tuple;
 	HeapTuple	newtuple;
@@ -1913,8 +1912,6 @@ CreateTransform(CreateTransformStmt *stmt)
 	values[Anum_pg_transform_trffromsql - 1] = ObjectIdGetDatum(fromsqlfuncid);
 	values[Anum_pg_transform_trftosql - 1] = ObjectIdGetDatum(tosqlfuncid);
 
-	MemSet(nulls, false, sizeof(nulls));
-
 	relation = table_open(TransformRelationId, RowExclusiveLock);
 
 	tuple = SearchSysCache2(TRFTYPELANG,
@@ -1922,6 +1919,8 @@ CreateTransform(CreateTransformStmt *stmt)
 							ObjectIdGetDatum(langid));
 	if (HeapTupleIsValid(tuple))
 	{
+		bool		replaces[Natts_pg_transform] = {0};
+
 		Form_pg_transform form = (Form_pg_transform) GETSTRUCT(tuple);
 
 		if (!stmt->replace)
@@ -1931,7 +1930,6 @@ CreateTransform(CreateTransformStmt *stmt)
 							format_type_be(typeid),
 							stmt->lang)));
 
-		MemSet(replaces, false, sizeof(replaces));
 		replaces[Anum_pg_transform_trffromsql - 1] = true;
 		replaces[Anum_pg_transform_trftosql - 1] = true;
 
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 2333aae467..579825c159 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -685,12 +685,10 @@ pg_prepared_statement(PG_FUNCTION_ARGS)
 		{
 			TupleDesc	result_desc;
 			Datum		values[8];
-			bool		nulls[8];
+			bool		nulls[8] = {0};
 
 			result_desc = prep_stmt->plansource->resultDesc;
 
-			MemSet(nulls, 0, sizeof(nulls));
-
 			values[0] = CStringGetTextDatum(prep_stmt->stmt_name);
 			values[1] = CStringGetTextDatum(prep_stmt->plansource->query_string);
 			values[2] = TimestampTzGetDatum(prep_stmt->prepare_time);
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index ef5b34a312..18f7a4ae86 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -9013,15 +9013,15 @@ ATAddForeignKeyConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
 						  bool recurse, bool recursing, LOCKMODE lockmode)
 {
 	Relation	pkrel;
-	int16		pkattnum[INDEX_MAX_KEYS];
-	int16		fkattnum[INDEX_MAX_KEYS];
-	Oid			pktypoid[INDEX_MAX_KEYS];
-	Oid			fktypoid[INDEX_MAX_KEYS];
-	Oid			opclasses[INDEX_MAX_KEYS];
-	Oid			pfeqoperators[INDEX_MAX_KEYS];
-	Oid			ppeqoperators[INDEX_MAX_KEYS];
-	Oid			ffeqoperators[INDEX_MAX_KEYS];
-	int16		fkdelsetcols[INDEX_MAX_KEYS];
+	int16		pkattnum[INDEX_MAX_KEYS] = {0};
+	int16		fkattnum[INDEX_MAX_KEYS] = {0};
+	Oid			pktypoid[INDEX_MAX_KEYS] = {0};
+	Oid			fktypoid[INDEX_MAX_KEYS] = {0};
+	Oid			opclasses[INDEX_MAX_KEYS] = {0};
+	Oid			pfeqoperators[INDEX_MAX_KEYS] = {0};
+	Oid			ppeqoperators[INDEX_MAX_KEYS] = {0};
+	Oid			ffeqoperators[INDEX_MAX_KEYS] = {0};
+	int16		fkdelsetcols[INDEX_MAX_KEYS] = {0};
 	int			i;
 	int			numfks,
 				numpks,
@@ -9113,16 +9113,6 @@ ATAddForeignKeyConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
 	 * Look up the referencing attributes to make sure they exist, and record
 	 * their attnums and type OIDs.
 	 */
-	MemSet(pkattnum, 0, sizeof(pkattnum));
-	MemSet(fkattnum, 0, sizeof(fkattnum));
-	MemSet(pktypoid, 0, sizeof(pktypoid));
-	MemSet(fktypoid, 0, sizeof(fktypoid));
-	MemSet(opclasses, 0, sizeof(opclasses));
-	MemSet(pfeqoperators, 0, sizeof(pfeqoperators));
-	MemSet(ppeqoperators, 0, sizeof(ppeqoperators));
-	MemSet(ffeqoperators, 0, sizeof(ffeqoperators));
-	MemSet(fkdelsetcols, 0, sizeof(fkdelsetcols));
-
 	numfks = transformColumnNameList(RelationGetRelid(rel),
 									 fkconstraint->fk_attrs,
 									 fkattnum, fktypoid);
@@ -11498,7 +11488,7 @@ validateForeignKeyConstraint(char *conname,
 {
 	TupleTableSlot *slot;
 	TableScanDesc scan;
-	Trigger		trig;
+	Trigger		trig = {0};
 	Snapshot	snapshot;
 	MemoryContext oldcxt;
 	MemoryContext perTupCxt;
@@ -11509,7 +11499,6 @@ validateForeignKeyConstraint(char *conname,
 	/*
 	 * Build a trigger call structure; we'll need it either way.
 	 */
-	MemSet(&trig, 0, sizeof(trig));
 	trig.tgoid = InvalidOid;
 	trig.tgname = conname;
 	trig.tgenabled = TRIGGER_FIRES_ON_ORIGIN;
@@ -12783,15 +12772,11 @@ ATExecAlterColumnType(AlteredTableInfo *tab, Relation rel,
 
 			int			one = 1;
 			bool		isNull;
-			Datum		valuesAtt[Natts_pg_attribute];
-			bool		nullsAtt[Natts_pg_attribute];
-			bool		replacesAtt[Natts_pg_attribute];
+			Datum		valuesAtt[Natts_pg_attribute] = {0};
+			bool		nullsAtt[Natts_pg_attribute] = {0};
+			bool		replacesAtt[Natts_pg_attribute] = {0};
 			HeapTuple	newTup;
 
-			MemSet(valuesAtt, 0, sizeof(valuesAtt));
-			MemSet(nullsAtt, false, sizeof(nullsAtt));
-			MemSet(replacesAtt, false, sizeof(replacesAtt));
-
 			missingval = array_get_element(missingval,
 										   1,
 										   &one,
@@ -19219,7 +19204,7 @@ ATDetachCheckNoForeignKeyRefs(Relation partition)
 		HeapTuple	tuple;
 		Form_pg_constraint constrForm;
 		Relation	rel;
-		Trigger		trig;
+		Trigger		trig = {0};
 
 		tuple = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constrOid));
 		if (!HeapTupleIsValid(tuple))
@@ -19232,7 +19217,6 @@ ATDetachCheckNoForeignKeyRefs(Relation partition)
 		/* prevent data changes into the referencing table until commit */
 		rel = table_open(constrForm->conrelid, ShareLock);
 
-		MemSet(&trig, 0, sizeof(trig));
 		trig.tgoid = InvalidOid;
 		trig.tgname = NameStr(constrForm->conname);
 		trig.tgenabled = TRIGGER_FIRES_ON_ORIGIN;
diff --git a/src/backend/commands/tablespace.c b/src/backend/commands/tablespace.c
index c8bdd9992a..cb7d46089a 100644
--- a/src/backend/commands/tablespace.c
+++ b/src/backend/commands/tablespace.c
@@ -238,7 +238,7 @@ CreateTableSpace(CreateTableSpaceStmt *stmt)
 #ifdef HAVE_SYMLINK
 	Relation	rel;
 	Datum		values[Natts_pg_tablespace];
-	bool		nulls[Natts_pg_tablespace];
+	bool		nulls[Natts_pg_tablespace] = {0};
 	HeapTuple	tuple;
 	Oid			tablespaceoid;
 	char	   *location;
@@ -340,8 +340,6 @@ CreateTableSpace(CreateTableSpaceStmt *stmt)
 	 */
 	rel = table_open(TableSpaceRelationId, RowExclusiveLock);
 
-	MemSet(nulls, false, sizeof(nulls));
-
 	if (IsBinaryUpgrade)
 	{
 		/* Use binary-upgrade override for tablespace oid */
diff --git a/src/backend/commands/typecmds.c b/src/backend/commands/typecmds.c
index 4f5e7c7ccb..4f58d29aa5 100644
--- a/src/backend/commands/typecmds.c
+++ b/src/backend/commands/typecmds.c
@@ -2570,9 +2570,9 @@ AlterDomainDefault(List *names, Node *defaultRaw)
 	Relation	rel;
 	char	   *defaultValue;
 	Node	   *defaultExpr = NULL; /* NULL if no default specified */
-	Datum		new_record[Natts_pg_type];
-	bool		new_record_nulls[Natts_pg_type];
-	bool		new_record_repl[Natts_pg_type];
+	Datum		new_record[Natts_pg_type] = {0};
+	bool		new_record_nulls[Natts_pg_type] = {0};
+	bool		new_record_repl[Natts_pg_type] = {0};
 	HeapTuple	newtuple;
 	Form_pg_type typTup;
 	ObjectAddress address;
@@ -2593,9 +2593,6 @@ AlterDomainDefault(List *names, Node *defaultRaw)
 	checkDomainOwner(tup);
 
 	/* Setup new tuple */
-	MemSet(new_record, (Datum) 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-	MemSet(new_record_repl, false, sizeof(new_record_repl));
 
 	/* Store the new default into the tuple */
 	if (defaultRaw)
diff --git a/src/backend/commands/user.c b/src/backend/commands/user.c
index 984305ba31..8f4cc86eda 100644
--- a/src/backend/commands/user.c
+++ b/src/backend/commands/user.c
@@ -74,8 +74,8 @@ CreateRole(ParseState *pstate, CreateRoleStmt *stmt)
 	Relation	pg_authid_rel;
 	TupleDesc	pg_authid_dsc;
 	HeapTuple	tuple;
-	Datum		new_record[Natts_pg_authid];
-	bool		new_record_nulls[Natts_pg_authid];
+	Datum		new_record[Natts_pg_authid] = {0};
+	bool		new_record_nulls[Natts_pg_authid] = {0};
 	Oid			roleid;
 	ListCell   *item;
 	ListCell   *option;
@@ -338,12 +338,8 @@ CreateRole(ParseState *pstate, CreateRoleStmt *stmt)
 	/*
 	 * Build a tuple to insert
 	 */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-
 	new_record[Anum_pg_authid_rolname - 1] =
 		DirectFunctionCall1(namein, CStringGetDatum(stmt->role));
-
 	new_record[Anum_pg_authid_rolsuper - 1] = BoolGetDatum(issuper);
 	new_record[Anum_pg_authid_rolinherit - 1] = BoolGetDatum(inherit);
 	new_record[Anum_pg_authid_rolcreaterole - 1] = BoolGetDatum(createrole);
@@ -492,9 +488,9 @@ CreateRole(ParseState *pstate, CreateRoleStmt *stmt)
 Oid
 AlterRole(ParseState *pstate, AlterRoleStmt *stmt)
 {
-	Datum		new_record[Natts_pg_authid];
-	bool		new_record_nulls[Natts_pg_authid];
-	bool		new_record_repl[Natts_pg_authid];
+	Datum		new_record[Natts_pg_authid] = {0};
+	bool		new_record_nulls[Natts_pg_authid] = {0};
+	bool		new_record_repl[Natts_pg_authid] = {0};
 	Relation	pg_authid_rel;
 	TupleDesc	pg_authid_dsc;
 	HeapTuple	tuple,
@@ -691,9 +687,6 @@ AlterRole(ParseState *pstate, AlterRoleStmt *stmt)
 	/*
 	 * Build an updated tuple, perusing the information just obtained
 	 */
-	MemSet(new_record, 0, sizeof(new_record));
-	MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-	MemSet(new_record_repl, false, sizeof(new_record_repl));
 
 	/*
 	 * issuper/createrole/etc
@@ -1440,9 +1433,8 @@ AddRoleMems(const char *rolename, Oid roleid,
 		Oid			memberid = lfirst_oid(iditem);
 		HeapTuple	authmem_tuple;
 		HeapTuple	tuple;
-		Datum		new_record[Natts_pg_auth_members];
-		bool		new_record_nulls[Natts_pg_auth_members];
-		bool		new_record_repl[Natts_pg_auth_members];
+		Datum		new_record[Natts_pg_auth_members] = {0};
+		bool		new_record_nulls[Natts_pg_auth_members] = {0};
 
 		/*
 		 * pg_database_owner is never a role member.  Lifting this restriction
@@ -1500,10 +1492,6 @@ AddRoleMems(const char *rolename, Oid roleid,
 		}
 
 		/* Build a tuple to insert or update */
-		MemSet(new_record, 0, sizeof(new_record));
-		MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-		MemSet(new_record_repl, false, sizeof(new_record_repl));
-
 		new_record[Anum_pg_auth_members_roleid - 1] = ObjectIdGetDatum(roleid);
 		new_record[Anum_pg_auth_members_member - 1] = ObjectIdGetDatum(memberid);
 		new_record[Anum_pg_auth_members_grantor - 1] = ObjectIdGetDatum(grantorId);
@@ -1511,6 +1499,8 @@ AddRoleMems(const char *rolename, Oid roleid,
 
 		if (HeapTupleIsValid(authmem_tuple))
 		{
+			bool		new_record_repl[Natts_pg_auth_members] = {0};
+
 			new_record_repl[Anum_pg_auth_members_grantor - 1] = true;
 			new_record_repl[Anum_pg_auth_members_admin_option - 1] = true;
 			tuple = heap_modify_tuple(authmem_tuple, pg_authmem_dsc,
@@ -1614,15 +1604,11 @@ DelRoleMems(const char *rolename, Oid roleid,
 		{
 			/* Just turn off the admin option */
 			HeapTuple	tuple;
-			Datum		new_record[Natts_pg_auth_members];
-			bool		new_record_nulls[Natts_pg_auth_members];
-			bool		new_record_repl[Natts_pg_auth_members];
+			Datum		new_record[Natts_pg_auth_members] = {0};
+			bool		new_record_nulls[Natts_pg_auth_members] = {0};
+			bool		new_record_repl[Natts_pg_auth_members] = {0};
 
 			/* Build a tuple to update with */
-			MemSet(new_record, 0, sizeof(new_record));
-			MemSet(new_record_nulls, false, sizeof(new_record_nulls));
-			MemSet(new_record_repl, false, sizeof(new_record_repl));
-
 			new_record[Anum_pg_auth_members_admin_option - 1] = BoolGetDatum(false);
 			new_record_repl[Anum_pg_auth_members_admin_option - 1] = true;
 
diff --git a/src/backend/libpq/auth.c b/src/backend/libpq/auth.c
index 2d9ab7edce..53fb7ca628 100644
--- a/src/backend/libpq/auth.c
+++ b/src/backend/libpq/auth.c
@@ -3022,7 +3022,7 @@ PerformRadiusTransaction(const char *server, const char *secret, const char *por
 	struct sockaddr_in localaddr;
 	struct sockaddr_in remoteaddr;
 #endif
-	struct addrinfo hint;
+	struct addrinfo hint = {0};
 	struct addrinfo *serveraddrs;
 	int			port;
 	socklen_t	addrsize;
@@ -3038,7 +3038,6 @@ PerformRadiusTransaction(const char *server, const char *secret, const char *por
 	if (identifier == NULL)
 		identifier = "postgresql";
 
-	MemSet(&hint, 0, sizeof(hint));
 	hint.ai_socktype = SOCK_DGRAM;
 	hint.ai_family = AF_UNSPEC;
 	port = atoi(portstr);
diff --git a/src/backend/libpq/pqcomm.c b/src/backend/libpq/pqcomm.c
index 75392a8bb7..803d166640 100644
--- a/src/backend/libpq/pqcomm.c
+++ b/src/backend/libpq/pqcomm.c
@@ -331,7 +331,7 @@ StreamServerPort(int family, const char *hostName, unsigned short portNumber,
 	char	   *service;
 	struct addrinfo *addrs = NULL,
 			   *addr;
-	struct addrinfo hint;
+	struct addrinfo hint = {0};
 	int			listen_index = 0;
 	int			added = 0;
 
@@ -343,7 +343,6 @@ StreamServerPort(int family, const char *hostName, unsigned short portNumber,
 #endif
 
 	/* Initialize hint structure */
-	MemSet(&hint, 0, sizeof(hint));
 	hint.ai_family = family;
 	hint.ai_flags = AI_PASSIVE;
 	hint.ai_socktype = SOCK_STREAM;
diff --git a/src/backend/optimizer/path/costsize.c b/src/backend/optimizer/path/costsize.c
index fcc26b01a4..1e0f1880c5 100644
--- a/src/backend/optimizer/path/costsize.c
+++ b/src/backend/optimizer/path/costsize.c
@@ -2926,13 +2926,12 @@ cost_agg(Path *path, PlannerInfo *root,
 	double		output_tuples;
 	Cost		startup_cost;
 	Cost		total_cost;
-	AggClauseCosts dummy_aggcosts;
+	const AggClauseCosts dummy_aggcosts = {0};
 
 	/* Use all-zero per-aggregate costs if NULL is passed */
 	if (aggcosts == NULL)
 	{
 		Assert(aggstrategy == AGG_HASHED);
-		MemSet(&dummy_aggcosts, 0, sizeof(AggClauseCosts));
 		aggcosts = &dummy_aggcosts;
 	}
 
diff --git a/src/backend/optimizer/path/indxpath.c b/src/backend/optimizer/path/indxpath.c
index 0ef70ad7f1..9c1b6305d3 100644
--- a/src/backend/optimizer/path/indxpath.c
+++ b/src/backend/optimizer/path/indxpath.c
@@ -238,9 +238,6 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
 	List	   *bitindexpaths;
 	List	   *bitjoinpaths;
 	List	   *joinorclauses;
-	IndexClauseSet rclauseset;
-	IndexClauseSet jclauseset;
-	IndexClauseSet eclauseset;
 	ListCell   *lc;
 
 	/* Skip the whole mess if no indexes */
@@ -253,6 +250,9 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
 	/* Examine each index in turn */
 	foreach(lc, rel->indexlist)
 	{
+		IndexClauseSet rclauseset = {0};
+		IndexClauseSet jclauseset = {0};
+		IndexClauseSet eclauseset = {0};
 		IndexOptInfo *index = (IndexOptInfo *) lfirst(lc);
 
 		/* Protect limited-size array in IndexClauseSets */
@@ -269,7 +269,6 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
 		/*
 		 * Identify the restriction clauses that can match the index.
 		 */
-		MemSet(&rclauseset, 0, sizeof(rclauseset));
 		match_restriction_clauses_to_index(root, index, &rclauseset);
 
 		/*
@@ -286,7 +285,6 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
 		 * step finds only "loose" join clauses that have not been merged into
 		 * EquivalenceClasses.  Also, collect join OR clauses for later.
 		 */
-		MemSet(&jclauseset, 0, sizeof(jclauseset));
 		match_join_clauses_to_index(root, rel, index,
 									&jclauseset, &joinorclauses);
 
@@ -294,7 +292,6 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
 		 * Look for EquivalenceClasses that can generate joinclauses matching
 		 * the index.
 		 */
-		MemSet(&eclauseset, 0, sizeof(eclauseset));
 		match_eclass_clauses_to_index(root, index,
 									  &eclauseset);
 
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c
index 06ad856eac..77cbe681e5 100644
--- a/src/backend/optimizer/plan/planner.c
+++ b/src/backend/optimizer/plan/planner.c
@@ -3350,9 +3350,8 @@ create_grouping_paths(PlannerInfo *root,
 	Query	   *parse = root->parse;
 	RelOptInfo *grouped_rel;
 	RelOptInfo *partially_grouped_rel;
-	AggClauseCosts agg_costs;
+	AggClauseCosts agg_costs = {0};
 
-	MemSet(&agg_costs, 0, sizeof(AggClauseCosts));
 	get_agg_clause_costs(root, AGGSPLIT_SIMPLE, &agg_costs);
 
 	/*
@@ -5908,16 +5907,14 @@ expression_planner_with_deps(Expr *expr,
 							 List **invalItems)
 {
 	Node	   *result;
-	PlannerGlobal glob;
-	PlannerInfo root;
+	PlannerGlobal glob = {0};
+	PlannerInfo root = {0};
 
 	/* Make up dummy planner state so we can use setrefs machinery */
-	MemSet(&glob, 0, sizeof(glob));
 	glob.type = T_PlannerGlobal;
 	glob.relationOids = NIL;
 	glob.invalItems = NIL;
 
-	MemSet(&root, 0, sizeof(root));
 	root.type = T_PlannerInfo;
 	root.glob = &glob;
 
diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c
index 9cef92cab2..f7fb2b3e6d 100644
--- a/src/backend/optimizer/plan/setrefs.c
+++ b/src/backend/optimizer/plan/setrefs.c
@@ -3285,18 +3285,16 @@ extract_query_dependencies(Node *query,
 						   List **invalItems,
 						   bool *hasRowSecurity)
 {
-	PlannerGlobal glob;
-	PlannerInfo root;
+	PlannerGlobal glob = {0};
+	PlannerInfo root = {0};
 
 	/* Make up dummy planner state so we can use this module's machinery */
-	MemSet(&glob, 0, sizeof(glob));
 	glob.type = T_PlannerGlobal;
 	glob.relationOids = NIL;
 	glob.invalItems = NIL;
 	/* Hack: we use glob.dependsOnRole to collect hasRowSecurity flags */
 	glob.dependsOnRole = false;
 
-	MemSet(&root, 0, sizeof(root));
 	root.type = T_PlannerInfo;
 	root.glob = &glob;
 
diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c
index 2a1d44b813..d69cb58b6a 100644
--- a/src/backend/parser/parse_target.c
+++ b/src/backend/parser/parse_target.c
@@ -1594,9 +1594,8 @@ expandRecordVariable(ParseState *pstate, Var *var, int levelsup)
 					 * to.  We have to build an additional level of ParseState
 					 * to keep in step with varlevelsup in the subselect.
 					 */
-					ParseState	mypstate;
+					ParseState	mypstate = {0};
 
-					MemSet(&mypstate, 0, sizeof(mypstate));
 					mypstate.parentParseState = pstate;
 					mypstate.p_rtable = rte->subquery->rtable;
 					/* don't bother filling the rest of the fake pstate */
@@ -1649,10 +1648,9 @@ expandRecordVariable(ParseState *pstate, Var *var, int levelsup)
 					 * in step with varlevelsup in the CTE; furthermore it
 					 * could be an outer CTE.
 					 */
-					ParseState	mypstate;
+					ParseState	mypstate = {0};
 					Index		levelsup;
 
-					MemSet(&mypstate, 0, sizeof(mypstate));
 					/* this loop must work, since GetCTEForRTE did */
 					for (levelsup = 0;
 						 levelsup < rte->ctelevelsup + netlevelsup;
diff --git a/src/backend/replication/logical/launcher.c b/src/backend/replication/logical/launcher.c
index 2bdab53e19..3bbd522724 100644
--- a/src/backend/replication/logical/launcher.c
+++ b/src/backend/replication/logical/launcher.c
@@ -938,8 +938,8 @@ pg_stat_get_subscription(PG_FUNCTION_ARGS)
 	for (i = 0; i < max_logical_replication_workers; i++)
 	{
 		/* for each row */
-		Datum		values[PG_STAT_GET_SUBSCRIPTION_COLS];
-		bool		nulls[PG_STAT_GET_SUBSCRIPTION_COLS];
+		Datum		values[PG_STAT_GET_SUBSCRIPTION_COLS] = {0};
+		bool		nulls[PG_STAT_GET_SUBSCRIPTION_COLS] = {0};
 		int			worker_pid;
 		LogicalRepWorker worker;
 
@@ -953,9 +953,6 @@ pg_stat_get_subscription(PG_FUNCTION_ARGS)
 
 		worker_pid = worker.proc->pid;
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		values[0] = ObjectIdGetDatum(worker.subid);
 		if (OidIsValid(worker.relid))
 			values[1] = ObjectIdGetDatum(worker.relid);
diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c
index 3c407ab964..ef2ca3fef7 100644
--- a/src/backend/replication/walsender.c
+++ b/src/backend/replication/walsender.c
@@ -402,7 +402,7 @@ IdentifySystem(void)
 	TupOutputState *tstate;
 	TupleDesc	tupdesc;
 	Datum		values[4];
-	bool		nulls[4];
+	bool		nulls[4] = {0};
 	TimeLineID	currTLI;
 
 	/*
@@ -437,7 +437,6 @@ IdentifySystem(void)
 	}
 
 	dest = CreateDestReceiver(DestRemoteSimple);
-	MemSet(nulls, false, sizeof(nulls));
 
 	/* need a tuple descriptor representing four columns */
 	tupdesc = CreateTemplateTupleDesc(4);
@@ -483,7 +482,7 @@ ReadReplicationSlot(ReadReplicationSlotCmd *cmd)
 	DestReceiver *dest;
 	TupOutputState *tstate;
 	TupleDesc	tupdesc;
-	Datum		values[READ_REPLICATION_SLOT_COLS];
+	Datum		values[READ_REPLICATION_SLOT_COLS] = {0};
 	bool		nulls[READ_REPLICATION_SLOT_COLS];
 
 	tupdesc = CreateTemplateTupleDesc(READ_REPLICATION_SLOT_COLS);
@@ -495,8 +494,7 @@ ReadReplicationSlot(ReadReplicationSlotCmd *cmd)
 	TupleDescInitBuiltinEntry(tupdesc, (AttrNumber) 3, "restart_tli",
 							  INT8OID, -1, 0);
 
-	MemSet(values, 0, READ_REPLICATION_SLOT_COLS * sizeof(Datum));
-	MemSet(nulls, true, READ_REPLICATION_SLOT_COLS * sizeof(bool));
+	memset(nulls, true, READ_REPLICATION_SLOT_COLS * sizeof(bool));
 
 	LWLockAcquire(ReplicationSlotControlLock, LW_SHARED);
 	slot = SearchNamedReplicationSlot(cmd->slotname, false);
@@ -859,13 +857,12 @@ StartReplication(StartReplicationCmd *cmd)
 		TupOutputState *tstate;
 		TupleDesc	tupdesc;
 		Datum		values[2];
-		bool		nulls[2];
+		bool		nulls[2] = {0};
 
 		snprintf(startpos_str, sizeof(startpos_str), "%X/%X",
 				 LSN_FORMAT_ARGS(sendTimeLineValidUpto));
 
 		dest = CreateDestReceiver(DestRemoteSimple);
-		MemSet(nulls, false, sizeof(nulls));
 
 		/*
 		 * Need a tuple descriptor representing two columns. int8 may seem
@@ -1043,7 +1040,7 @@ CreateReplicationSlot(CreateReplicationSlotCmd *cmd)
 	TupOutputState *tstate;
 	TupleDesc	tupdesc;
 	Datum		values[4];
-	bool		nulls[4];
+	bool		nulls[4] = {0};
 
 	Assert(!MyReplicationSlot);
 
@@ -1178,7 +1175,6 @@ CreateReplicationSlot(CreateReplicationSlotCmd *cmd)
 			 LSN_FORMAT_ARGS(MyReplicationSlot->data.confirmed_flush));
 
 	dest = CreateDestReceiver(DestRemoteSimple);
-	MemSet(nulls, false, sizeof(nulls));
 
 	/*----------
 	 * Need a tuple descriptor representing four columns:
@@ -3527,7 +3523,6 @@ pg_stat_get_wal_senders(PG_FUNCTION_ARGS)
 			}
 		}
 
-		memset(nulls, 0, sizeof(nulls));
 		values[0] = Int32GetDatum(pid);
 
 		if (!has_privs_of_role(GetUserId(), ROLE_PG_READ_ALL_STATS))
@@ -3537,10 +3532,12 @@ pg_stat_get_wal_senders(PG_FUNCTION_ARGS)
 			 * can see details. Other users only get the pid value to know
 			 * it's a walsender, but no details.
 			 */
-			MemSet(&nulls[1], true, PG_STAT_GET_WAL_SENDERS_COLS - 1);
+			nulls[0] = false;
+			memset(&nulls[1], true, PG_STAT_GET_WAL_SENDERS_COLS - 1);
 		}
 		else
 		{
+			memset(nulls, 0, sizeof(nulls));
 			values[1] = CStringGetTextDatum(WalSndGetStateString(state));
 
 			if (XLogRecPtrIsInvalid(sentPtr))
diff --git a/src/backend/rewrite/rewriteDefine.c b/src/backend/rewrite/rewriteDefine.c
index 185bf5fbff..a5a1fb887f 100644
--- a/src/backend/rewrite/rewriteDefine.c
+++ b/src/backend/rewrite/rewriteDefine.c
@@ -67,8 +67,7 @@ InsertRule(const char *rulname,
 	char	   *evqual = nodeToString(event_qual);
 	char	   *actiontree = nodeToString((Node *) action);
 	Datum		values[Natts_pg_rewrite];
-	bool		nulls[Natts_pg_rewrite];
-	bool		replaces[Natts_pg_rewrite];
+	bool		nulls[Natts_pg_rewrite] = {0};
 	NameData	rname;
 	Relation	pg_rewrite_desc;
 	HeapTuple	tup,
@@ -81,8 +80,6 @@ InsertRule(const char *rulname,
 	/*
 	 * Set up *nulls and *values arrays
 	 */
-	MemSet(nulls, false, sizeof(nulls));
-
 	namestrcpy(&rname, rulname);
 	values[Anum_pg_rewrite_rulename - 1] = NameGetDatum(&rname);
 	values[Anum_pg_rewrite_ev_class - 1] = ObjectIdGetDatum(eventrel_oid);
@@ -106,6 +103,8 @@ InsertRule(const char *rulname,
 
 	if (HeapTupleIsValid(oldtup))
 	{
+		bool		replaces[Natts_pg_rewrite] = {0};
+
 		if (!replace)
 			ereport(ERROR,
 					(errcode(ERRCODE_DUPLICATE_OBJECT),
@@ -115,7 +114,6 @@ InsertRule(const char *rulname,
 		/*
 		 * When replacing, we don't need to replace every attribute
 		 */
-		MemSet(replaces, false, sizeof(replaces));
 		replaces[Anum_pg_rewrite_ev_type - 1] = true;
 		replaces[Anum_pg_rewrite_is_instead - 1] = true;
 		replaces[Anum_pg_rewrite_ev_qual - 1] = true;
diff --git a/src/backend/storage/lmgr/lock.c b/src/backend/storage/lmgr/lock.c
index 5f5803f681..ae6a1b1116 100644
--- a/src/backend/storage/lmgr/lock.c
+++ b/src/backend/storage/lmgr/lock.c
@@ -597,13 +597,12 @@ DoLockModesConflict(LOCKMODE mode1, LOCKMODE mode2)
 bool
 LockHeldByMe(const LOCKTAG *locktag, LOCKMODE lockmode)
 {
-	LOCALLOCKTAG localtag;
+	LOCALLOCKTAG localtag = {0};
 	LOCALLOCK  *locallock;
 
 	/*
 	 * See if there is a LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
@@ -635,7 +634,7 @@ LockHasWaiters(const LOCKTAG *locktag, LOCKMODE lockmode, bool sessionLock)
 {
 	LOCKMETHODID lockmethodid = locktag->locktag_lockmethodid;
 	LockMethod	lockMethodTable;
-	LOCALLOCKTAG localtag;
+	LOCALLOCKTAG localtag = {0};
 	LOCALLOCK  *locallock;
 	LOCK	   *lock;
 	PROCLOCK   *proclock;
@@ -658,7 +657,6 @@ LockHasWaiters(const LOCKTAG *locktag, LOCKMODE lockmode, bool sessionLock)
 	/*
 	 * Find the LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
@@ -777,7 +775,7 @@ LockAcquireExtended(const LOCKTAG *locktag,
 {
 	LOCKMETHODID lockmethodid = locktag->locktag_lockmethodid;
 	LockMethod	lockMethodTable;
-	LOCALLOCKTAG localtag;
+	LOCALLOCKTAG localtag = {0};
 	LOCALLOCK  *locallock;
 	LOCK	   *lock;
 	PROCLOCK   *proclock;
@@ -820,7 +818,6 @@ LockAcquireExtended(const LOCKTAG *locktag,
 	/*
 	 * Find or create a LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
@@ -1976,7 +1973,7 @@ LockRelease(const LOCKTAG *locktag, LOCKMODE lockmode, bool sessionLock)
 {
 	LOCKMETHODID lockmethodid = locktag->locktag_lockmethodid;
 	LockMethod	lockMethodTable;
-	LOCALLOCKTAG localtag;
+	LOCALLOCKTAG localtag = {0};
 	LOCALLOCK  *locallock;
 	LOCK	   *lock;
 	PROCLOCK   *proclock;
@@ -1999,7 +1996,6 @@ LockRelease(const LOCKTAG *locktag, LOCKMODE lockmode, bool sessionLock)
 	/*
 	 * Find the LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
diff --git a/src/backend/storage/lmgr/lwlock.c b/src/backend/storage/lmgr/lwlock.c
index 38317edaf9..ce5e5c073f 100644
--- a/src/backend/storage/lmgr/lwlock.c
+++ b/src/backend/storage/lmgr/lwlock.c
@@ -384,7 +384,7 @@ print_lwlock_stats(int code, Datum arg)
 static lwlock_stats *
 get_lwlock_stats_entry(LWLock *lock)
 {
-	lwlock_stats_key key;
+	lwlock_stats_key key = {0};
 	lwlock_stats *lwstats;
 	bool		found;
 
@@ -397,7 +397,6 @@ get_lwlock_stats_entry(LWLock *lock)
 		return &lwlock_stats_dummy;
 
 	/* Fetch or create the entry. */
-	MemSet(&key, 0, sizeof(key));
 	key.tranche = lock->tranche;
 	key.instance = lock;
 	lwstats = hash_search(lwlock_stats_htab, &key, HASH_ENTER, &found);
diff --git a/src/backend/utils/adt/acl.c b/src/backend/utils/adt/acl.c
index b7fd3bcf05..6fa58dd8eb 100644
--- a/src/backend/utils/adt/acl.c
+++ b/src/backend/utils/adt/acl.c
@@ -1785,7 +1785,7 @@ aclexplode(PG_FUNCTION_ARGS)
 		{
 			Datum		result;
 			Datum		values[4];
-			bool		nulls[4];
+			bool		nulls[4] = {0};
 			HeapTuple	tuple;
 
 			values[0] = ObjectIdGetDatum(aidata->ai_grantor);
@@ -1793,8 +1793,6 @@ aclexplode(PG_FUNCTION_ARGS)
 			values[2] = CStringGetTextDatum(convert_aclright_to_string(priv_bit));
 			values[3] = BoolGetDatum((ACLITEM_GET_GOPTIONS(*aidata) & priv_bit) != 0);
 
-			MemSet(nulls, 0, sizeof(nulls));
-
 			tuple = heap_form_tuple(funcctx->tuple_desc, values, nulls);
 			result = HeapTupleGetDatum(tuple);
 
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index b0c37ede87..fb167f226a 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -742,11 +742,10 @@ ReadArrayStr(char *arrayStr,
 	bool		eoArray = false;
 	bool		hasnull;
 	int32		totbytes;
-	int			indx[MAXDIM],
+	int			indx[MAXDIM] = {0},
 				prod[MAXDIM];
 
 	mda_get_prod(ndim, dim, prod);
-	MemSet(indx, 0, sizeof(indx));
 
 	/* Initialize is-null markers to true */
 	memset(nulls, true, nitems * sizeof(bool));
diff --git a/src/backend/utils/adt/datetime.c b/src/backend/utils/adt/datetime.c
index 4c12c4d663..8976f4e9f7 100644
--- a/src/backend/utils/adt/datetime.c
+++ b/src/backend/utils/adt/datetime.c
@@ -4924,13 +4924,13 @@ pg_timezone_abbrevs(PG_FUNCTION_ARGS)
 	Datum		result;
 	HeapTuple	tuple;
 	Datum		values[3];
-	bool		nulls[3];
+	bool		nulls[3] = {0};
 	const datetkn *tp;
 	char		buffer[TOKMAXLEN + 1];
 	int			gmtoffset;
 	bool		is_dst;
 	unsigned char *p;
-	struct pg_itm_in itm_in;
+	struct pg_itm_in itm_in = {0};
 	Interval   *resInterval;
 
 	/* stuff done only on the first call of the function */
@@ -5011,8 +5011,6 @@ pg_timezone_abbrevs(PG_FUNCTION_ARGS)
 			break;
 	}
 
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/*
 	 * Convert name to text, using upcasing conversion that is the inverse of
 	 * what ParseDateTime() uses.
@@ -5024,7 +5022,6 @@ pg_timezone_abbrevs(PG_FUNCTION_ARGS)
 	values[0] = CStringGetTextDatum(buffer);
 
 	/* Convert offset (in seconds) to an interval; can't overflow */
-	MemSet(&itm_in, 0, sizeof(struct pg_itm_in));
 	itm_in.tm_usec = (int64) gmtoffset * USECS_PER_SEC;
 	resInterval = (Interval *) palloc(sizeof(Interval));
 	(void) itmin2interval(&itm_in, resInterval);
@@ -5051,13 +5048,13 @@ pg_timezone_names(PG_FUNCTION_ARGS)
 	pg_tzenum  *tzenum;
 	pg_tz	   *tz;
 	Datum		values[4];
-	bool		nulls[4];
+	bool		nulls[4] = {0};
 	int			tzoff;
 	struct pg_tm tm;
 	fsec_t		fsec;
 	const char *tzn;
 	Interval   *resInterval;
-	struct pg_itm_in itm_in;
+	struct pg_itm_in itm_in = {0};
 
 	SetSingleFuncCall(fcinfo, 0);
 
@@ -5088,13 +5085,10 @@ pg_timezone_names(PG_FUNCTION_ARGS)
 		if (tzn && strlen(tzn) > 31)
 			continue;
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		values[0] = CStringGetTextDatum(pg_get_timezone_name(tz));
 		values[1] = CStringGetTextDatum(tzn ? tzn : "");
 
 		/* Convert tzoff to an interval; can't overflow */
-		MemSet(&itm_in, 0, sizeof(struct pg_itm_in));
 		itm_in.tm_usec = (int64) -tzoff * USECS_PER_SEC;
 		resInterval = (Interval *) palloc(sizeof(Interval));
 		(void) itmin2interval(&itm_in, resInterval);
diff --git a/src/backend/utils/adt/lockfuncs.c b/src/backend/utils/adt/lockfuncs.c
index dedee7af5c..613f5f9bec 100644
--- a/src/backend/utils/adt/lockfuncs.c
+++ b/src/backend/utils/adt/lockfuncs.c
@@ -172,8 +172,8 @@ pg_lock_status(PG_FUNCTION_ARGS)
 		LOCKMODE	mode = 0;
 		const char *locktypename;
 		char		tnbuf[32];
-		Datum		values[NUM_LOCK_STATUS_COLUMNS];
-		bool		nulls[NUM_LOCK_STATUS_COLUMNS];
+		Datum		values[NUM_LOCK_STATUS_COLUMNS] = {0};
+		bool		nulls[NUM_LOCK_STATUS_COLUMNS] = {0};
 		HeapTuple	tuple;
 		Datum		result;
 		LockInstanceData *instance;
@@ -230,9 +230,6 @@ pg_lock_status(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
-
 		if (instance->locktag.locktag_type <= LOCKTAG_LAST_TYPE)
 			locktypename = LockTagTypeNames[instance->locktag.locktag_type];
 		else
@@ -359,8 +356,8 @@ pg_lock_status(PG_FUNCTION_ARGS)
 
 		PREDICATELOCKTARGETTAG *predTag = &(predLockData->locktags[mystatus->predLockIdx]);
 		SERIALIZABLEXACT *xact = &(predLockData->xacts[mystatus->predLockIdx]);
-		Datum		values[NUM_LOCK_STATUS_COLUMNS];
-		bool		nulls[NUM_LOCK_STATUS_COLUMNS];
+		Datum		values[NUM_LOCK_STATUS_COLUMNS] = {0};
+		bool		nulls[NUM_LOCK_STATUS_COLUMNS] = {0};
 		HeapTuple	tuple;
 		Datum		result;
 
@@ -369,8 +366,6 @@ pg_lock_status(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, false, sizeof(nulls));
 
 		/* lock type */
 		lockType = GET_PREDICATELOCKTARGETTAG_TYPE(*predTag);
diff --git a/src/backend/utils/adt/partitionfuncs.c b/src/backend/utils/adt/partitionfuncs.c
index 0243bc061f..109dc8023e 100644
--- a/src/backend/utils/adt/partitionfuncs.c
+++ b/src/backend/utils/adt/partitionfuncs.c
@@ -113,8 +113,8 @@ pg_partition_tree(PG_FUNCTION_ARGS)
 	if (funcctx->call_cntr < list_length(partitions))
 	{
 		Datum		result;
-		Datum		values[PG_PARTITION_TREE_COLS];
-		bool		nulls[PG_PARTITION_TREE_COLS];
+		Datum		values[PG_PARTITION_TREE_COLS] = {0};
+		bool		nulls[PG_PARTITION_TREE_COLS] = {0};
 		HeapTuple	tuple;
 		Oid			parentid = InvalidOid;
 		Oid			relid = list_nth_oid(partitions, funcctx->call_cntr);
@@ -126,8 +126,6 @@ pg_partition_tree(PG_FUNCTION_ARGS)
 		/*
 		 * Form tuple with appropriate data.
 		 */
-		MemSet(nulls, 0, sizeof(nulls));
-		MemSet(values, 0, sizeof(values));
 
 		/* relid */
 		values[0] = ObjectIdGetDatum(relid);
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 893690dad5..0a6369fdba 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -488,13 +488,10 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 	{
 		LocalPgBackendStatus *local_beentry;
 		PgBackendStatus *beentry;
-		Datum		values[PG_STAT_GET_PROGRESS_COLS];
-		bool		nulls[PG_STAT_GET_PROGRESS_COLS];
+		Datum		values[PG_STAT_GET_PROGRESS_COLS] = {0};
+		bool		nulls[PG_STAT_GET_PROGRESS_COLS] = {0};
 		int			i;
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
 
 		if (!local_beentry)
@@ -551,17 +548,14 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 	for (curr_backend = 1; curr_backend <= num_backends; curr_backend++)
 	{
 		/* for each row */
-		Datum		values[PG_STAT_GET_ACTIVITY_COLS];
-		bool		nulls[PG_STAT_GET_ACTIVITY_COLS];
+		Datum		values[PG_STAT_GET_ACTIVITY_COLS] = {0};
+		bool		nulls[PG_STAT_GET_ACTIVITY_COLS] = {0};
 		LocalPgBackendStatus *local_beentry;
 		PgBackendStatus *beentry;
 		PGPROC	   *proc;
 		const char *wait_event_type = NULL;
 		const char *wait_event = NULL;
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		/* Get the next one in the list */
 		local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
 		if (!local_beentry)
@@ -1747,15 +1741,11 @@ pg_stat_get_wal(PG_FUNCTION_ARGS)
 {
 #define PG_STAT_GET_WAL_COLS	9
 	TupleDesc	tupdesc;
-	Datum		values[PG_STAT_GET_WAL_COLS];
-	bool		nulls[PG_STAT_GET_WAL_COLS];
+	Datum		values[PG_STAT_GET_WAL_COLS] = {0};
+	bool		nulls[PG_STAT_GET_WAL_COLS] = {0};
 	char		buf[256];
 	PgStat_WalStats *wal_stats;
 
-	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* Initialise attributes information in the tuple descriptor */
 	tupdesc = CreateTemplateTupleDesc(PG_STAT_GET_WAL_COLS);
 	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "wal_records",
@@ -1827,7 +1817,7 @@ pg_stat_get_slru(PG_FUNCTION_ARGS)
 	{
 		/* for each row */
 		Datum		values[PG_STAT_GET_SLRU_COLS];
-		bool		nulls[PG_STAT_GET_SLRU_COLS];
+		bool		nulls[PG_STAT_GET_SLRU_COLS] = {0};
 		PgStat_SLRUStats stat;
 		const char *name;
 
@@ -1837,8 +1827,6 @@ pg_stat_get_slru(PG_FUNCTION_ARGS)
 			break;
 
 		stat = stats[i];
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
 
 		values[0] = PointerGetDatum(cstring_to_text(name));
 		values[1] = Int64GetDatum(stat.blocks_zeroed);
@@ -2201,14 +2189,10 @@ Datum
 pg_stat_get_archiver(PG_FUNCTION_ARGS)
 {
 	TupleDesc	tupdesc;
-	Datum		values[7];
-	bool		nulls[7];
+	Datum		values[7] = {0};
+	bool		nulls[7] = {0};
 	PgStat_ArchiverStats *archiver_stats;
 
-	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* Initialise attributes information in the tuple descriptor */
 	tupdesc = CreateTemplateTupleDesc(7);
 	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "archived_count",
@@ -2274,15 +2258,11 @@ pg_stat_get_replication_slot(PG_FUNCTION_ARGS)
 	text	   *slotname_text = PG_GETARG_TEXT_P(0);
 	NameData	slotname;
 	TupleDesc	tupdesc;
-	Datum		values[PG_STAT_GET_REPLICATION_SLOT_COLS];
-	bool		nulls[PG_STAT_GET_REPLICATION_SLOT_COLS];
+	Datum		values[PG_STAT_GET_REPLICATION_SLOT_COLS] = {0};
+	bool		nulls[PG_STAT_GET_REPLICATION_SLOT_COLS] = {0};
 	PgStat_StatReplSlotEntry *slotent;
 	PgStat_StatReplSlotEntry allzero;
 
-	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* Initialise attributes information in the tuple descriptor */
 	tupdesc = CreateTemplateTupleDesc(PG_STAT_GET_REPLICATION_SLOT_COLS);
 	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "slot_name",
@@ -2348,8 +2328,8 @@ pg_stat_get_subscription_stats(PG_FUNCTION_ARGS)
 #define PG_STAT_GET_SUBSCRIPTION_STATS_COLS	4
 	Oid			subid = PG_GETARG_OID(0);
 	TupleDesc	tupdesc;
-	Datum		values[PG_STAT_GET_SUBSCRIPTION_STATS_COLS];
-	bool		nulls[PG_STAT_GET_SUBSCRIPTION_STATS_COLS];
+	Datum		values[PG_STAT_GET_SUBSCRIPTION_STATS_COLS] = {0};
+	bool		nulls[PG_STAT_GET_SUBSCRIPTION_STATS_COLS] = {0};
 	PgStat_StatSubEntry *subentry;
 	PgStat_StatSubEntry allzero;
 
@@ -2368,10 +2348,6 @@ pg_stat_get_subscription_stats(PG_FUNCTION_ARGS)
 					   TIMESTAMPTZOID, -1, 0);
 	BlessTupleDesc(tupdesc);
 
-	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	if (!subentry)
 	{
 		/* If the subscription is not found, initialise its stats */
diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c
index fa1f589fad..6f99b5b243 100644
--- a/src/backend/utils/adt/selfuncs.c
+++ b/src/backend/utils/adt/selfuncs.c
@@ -6642,10 +6642,10 @@ btcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 			   double *indexPages)
 {
 	IndexOptInfo *index = path->indexinfo;
-	GenericCosts costs;
+	GenericCosts costs = {0};
 	Oid			relid;
 	AttrNumber	colnum;
-	VariableStatData vardata;
+	VariableStatData vardata = {0};
 	double		numIndexTuples;
 	Cost		descentCost;
 	List	   *indexBoundQuals;
@@ -6797,7 +6797,6 @@ btcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	/*
 	 * Now do generic index cost estimation.
 	 */
-	MemSet(&costs, 0, sizeof(costs));
 	costs.numIndexTuples = numIndexTuples;
 
 	genericcostestimate(root, path, loop_count, &costs);
@@ -6842,8 +6841,6 @@ btcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 	 * ordering, but don't negate it entirely.  Before 8.0 we divided the
 	 * correlation by the number of columns, but that seems too strong.)
 	 */
-	MemSet(&vardata, 0, sizeof(vardata));
-
 	if (index->indexkeys[0] != 0)
 	{
 		/* Simple variable --- look to stats for the underlying table */
@@ -6947,9 +6944,7 @@ hashcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 				 Selectivity *indexSelectivity, double *indexCorrelation,
 				 double *indexPages)
 {
-	GenericCosts costs;
-
-	MemSet(&costs, 0, sizeof(costs));
+	GenericCosts costs = {0};
 
 	genericcostestimate(root, path, loop_count, &costs);
 
@@ -6992,11 +6987,9 @@ gistcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 				 double *indexPages)
 {
 	IndexOptInfo *index = path->indexinfo;
-	GenericCosts costs;
+	GenericCosts costs = {0};
 	Cost		descentCost;
 
-	MemSet(&costs, 0, sizeof(costs));
-
 	genericcostestimate(root, path, loop_count, &costs);
 
 	/*
@@ -7049,11 +7042,9 @@ spgcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
 				double *indexPages)
 {
 	IndexOptInfo *index = path->indexinfo;
-	GenericCosts costs;
+	GenericCosts costs = {0};
 	Cost		descentCost;
 
-	MemSet(&costs, 0, sizeof(costs));
-
 	genericcostestimate(root, path, loop_count, &costs);
 
 	/*
diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index f70f829d83..0a17f45e92 100644
--- a/src/backend/utils/adt/timestamp.c
+++ b/src/backend/utils/adt/timestamp.c
@@ -2403,7 +2403,7 @@ interval_cmp_value(const Interval *interval)
 }
 
 static int
-interval_cmp_internal(Interval *interval1, Interval *interval2)
+interval_cmp_internal(const Interval *interval1, const Interval *interval2)
 {
 	INT128		span1 = interval_cmp_value(interval1);
 	INT128		span2 = interval_cmp_value(interval2);
@@ -5777,7 +5777,7 @@ generate_series_timestamp(PG_FUNCTION_ARGS)
 		Timestamp	finish = PG_GETARG_TIMESTAMP(1);
 		Interval   *step = PG_GETARG_INTERVAL_P(2);
 		MemoryContext oldcontext;
-		Interval	interval_zero;
+		Interval	interval_zero = {0};
 
 		/* create a function context for cross-call persistence */
 		funcctx = SRF_FIRSTCALL_INIT();
@@ -5800,7 +5800,6 @@ generate_series_timestamp(PG_FUNCTION_ARGS)
 		fctx->step = *step;
 
 		/* Determine sign of the interval */
-		MemSet(&interval_zero, 0, sizeof(Interval));
 		fctx->step_sign = interval_cmp_internal(&fctx->step, &interval_zero);
 
 		if (fctx->step_sign == 0)
@@ -5857,7 +5856,7 @@ generate_series_timestamptz(PG_FUNCTION_ARGS)
 		TimestampTz finish = PG_GETARG_TIMESTAMPTZ(1);
 		Interval   *step = PG_GETARG_INTERVAL_P(2);
 		MemoryContext oldcontext;
-		Interval	interval_zero;
+		Interval	interval_zero = {0};
 
 		/* create a function context for cross-call persistence */
 		funcctx = SRF_FIRSTCALL_INIT();
@@ -5880,7 +5879,6 @@ generate_series_timestamptz(PG_FUNCTION_ARGS)
 		fctx->step = *step;
 
 		/* Determine sign of the interval */
-		MemSet(&interval_zero, 0, sizeof(Interval));
 		fctx->step_sign = interval_cmp_internal(&fctx->step, &interval_zero);
 
 		if (fctx->step_sign == 0)
diff --git a/src/backend/utils/adt/tsrank.c b/src/backend/utils/adt/tsrank.c
index 3858fc5928..7d78219b62 100644
--- a/src/backend/utils/adt/tsrank.c
+++ b/src/backend/utils/adt/tsrank.c
@@ -853,7 +853,7 @@ calc_rank_cd(const float4 *arrdata, TSVector txt, TSQuery query, int method)
 	int			len,
 				i,
 				doclen = 0;
-	CoverExt	ext;
+	CoverExt	ext = {0};
 	double		Wdoc = 0.0;
 	double		invws[lengthof(weights)];
 	double		SumDist = 0.0,
@@ -883,7 +883,6 @@ calc_rank_cd(const float4 *arrdata, TSVector txt, TSQuery query, int method)
 		return 0.0;
 	}
 
-	MemSet(&ext, 0, sizeof(CoverExt));
 	while (Cover(doc, doclen, &qr, &ext))
 	{
 		double		Cpos = 0.0;
diff --git a/src/backend/utils/cache/relfilenumbermap.c b/src/backend/utils/cache/relfilenumbermap.c
index c4245d5ccd..ada0efa8f2 100644
--- a/src/backend/utils/cache/relfilenumbermap.c
+++ b/src/backend/utils/cache/relfilenumbermap.c
@@ -143,7 +143,7 @@ RelidByRelfilenumber(Oid reltablespace, RelFileNumber relfilenumber)
 	SysScanDesc scandesc;
 	Relation	relation;
 	HeapTuple	ntp;
-	ScanKeyData skey[2];
+	ScanKeyData skey[2] = {0};
 	Oid			relid;
 
 	if (RelfilenumberMapHash == NULL)
@@ -153,7 +153,6 @@ RelidByRelfilenumber(Oid reltablespace, RelFileNumber relfilenumber)
 	if (reltablespace == MyDatabaseTableSpace)
 		reltablespace = 0;
 
-	MemSet(&key, 0, sizeof(key));
 	key.reltablespace = reltablespace;
 	key.relfilenumber = relfilenumber;
 
diff --git a/src/backend/utils/cache/ts_cache.c b/src/backend/utils/cache/ts_cache.c
index 24808dfbb1..70e88fd228 100644
--- a/src/backend/utils/cache/ts_cache.c
+++ b/src/backend/utils/cache/ts_cache.c
@@ -414,7 +414,7 @@ lookup_ts_config_cache(Oid cfgId)
 		ScanKeyData mapskey;
 		SysScanDesc mapscan;
 		HeapTuple	maptup;
-		ListDictionary maplists[MAXTOKENTYPE + 1];
+		ListDictionary maplists[MAXTOKENTYPE + 1] = {0};
 		Oid			mapdicts[MAXDICTSPERTT];
 		int			maxtokentype;
 		int			ndicts;
@@ -468,7 +468,6 @@ lookup_ts_config_cache(Oid cfgId)
 		 * see the entries in maptokentype order, and in mapseqno order for
 		 * each token type, even though we didn't explicitly ask for that.
 		 */
-		MemSet(maplists, 0, sizeof(maplists));
 		maxtokentype = 0;
 		ndicts = 0;
 
diff --git a/src/backend/utils/misc/ps_status.c b/src/backend/utils/misc/ps_status.c
index 8520ce76bb..264d0ab1df 100644
--- a/src/backend/utils/misc/ps_status.c
+++ b/src/backend/utils/misc/ps_status.c
@@ -376,7 +376,7 @@ set_ps_display(const char *activity)
 #ifdef PS_USE_CLOBBER_ARGV
 	/* pad unused memory; need only clobber remainder of old status string */
 	if (last_status_len > ps_buffer_cur_len)
-		MemSet(ps_buffer + ps_buffer_cur_len, PS_PADDING,
+		memset(ps_buffer + ps_buffer_cur_len, PS_PADDING,
 			   last_status_len - ps_buffer_cur_len);
 	last_status_len = ps_buffer_cur_len;
 #endif							/* PS_USE_CLOBBER_ARGV */
diff --git a/src/backend/utils/misc/timeout.c b/src/backend/utils/misc/timeout.c
index 6f5e08bc30..284b9153ea 100644
--- a/src/backend/utils/misc/timeout.c
+++ b/src/backend/utils/misc/timeout.c
@@ -211,13 +211,11 @@ schedule_alarm(TimestampTz now)
 {
 	if (num_active_timeouts > 0)
 	{
-		struct itimerval timeval;
+		struct itimerval timeval = {0};
 		TimestampTz nearest_timeout;
 		long		secs;
 		int			usecs;
 
-		MemSet(&timeval, 0, sizeof(struct itimerval));
-
 		/*
 		 * If we think there's a signal pending, but current time is more than
 		 * 10ms past when the signal was due, then assume that the timeout
diff --git a/src/backend/utils/mmgr/portalmem.c b/src/backend/utils/mmgr/portalmem.c
index d549f66d4a..3a161bdb88 100644
--- a/src/backend/utils/mmgr/portalmem.c
+++ b/src/backend/utils/mmgr/portalmem.c
@@ -1146,14 +1146,12 @@ pg_cursor(PG_FUNCTION_ARGS)
 	{
 		Portal		portal = hentry->portal;
 		Datum		values[6];
-		bool		nulls[6];
+		bool		nulls[6] = {0};
 
 		/* report only "visible" entries */
 		if (!portal->visible)
 			continue;
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		values[0] = CStringGetTextDatum(portal->name);
 		values[1] = CStringGetTextDatum(portal->sourceText);
 		values[2] = BoolGetDatum(portal->cursorOptions & CURSOR_OPT_HOLD);
diff --git a/src/bin/pg_basebackup/pg_basebackup.c b/src/bin/pg_basebackup/pg_basebackup.c
index 4445a86aee..79b23fa7d7 100644
--- a/src/bin/pg_basebackup/pg_basebackup.c
+++ b/src/bin/pg_basebackup/pg_basebackup.c
@@ -447,7 +447,7 @@ reached_end_position(XLogRecPtr segendpos, uint32 timeline,
 	{
 #ifndef WIN32
 		fd_set		fds;
-		struct timeval tv;
+		struct timeval tv = {0};
 		int			r;
 
 		/*
@@ -457,16 +457,13 @@ reached_end_position(XLogRecPtr segendpos, uint32 timeline,
 		FD_ZERO(&fds);
 		FD_SET(bgpipe[0], &fds);
 
-		MemSet(&tv, 0, sizeof(tv));
-
 		r = select(bgpipe[0] + 1, &fds, NULL, NULL, &tv);
 		if (r == 1)
 		{
-			char		xlogend[64];
+			char		xlogend[64] = {0};
 			uint32		hi,
 						lo;
 
-			MemSet(xlogend, 0, sizeof(xlogend));
 			r = read(bgpipe[0], xlogend, sizeof(xlogend) - 1);
 			if (r < 0)
 				pg_fatal("could not read from ready pipe: %m");
@@ -528,11 +525,10 @@ typedef struct
 static int
 LogStreamerMain(logstreamer_param *param)
 {
-	StreamCtl	stream;
+	StreamCtl	stream = {0};
 
 	in_log_streamer = true;
 
-	MemSet(&stream, 0, sizeof(stream));
 	stream.startpos = param->startptr;
 	stream.timeline = param->timeline;
 	stream.sysidentifier = param->sysidentifier;
@@ -1952,7 +1948,6 @@ BaseBackup(char *compression_algorithm, char *compression_detail,
 	else
 		starttli = latesttli;
 	PQclear(res);
-	MemSet(xlogend, 0, sizeof(xlogend));
 
 	if (verbose && includewal != NO_WAL)
 		pg_log_info("write-ahead log start point: %s on timeline %u",
diff --git a/src/bin/pg_basebackup/pg_receivewal.c b/src/bin/pg_basebackup/pg_receivewal.c
index ea3902c971..f064cff4ab 100644
--- a/src/bin/pg_basebackup/pg_receivewal.c
+++ b/src/bin/pg_basebackup/pg_receivewal.c
@@ -564,11 +564,9 @@ StreamLog(void)
 {
 	XLogRecPtr	serverpos;
 	TimeLineID	servertli;
-	StreamCtl	stream;
+	StreamCtl	stream = {0};
 	char	   *sysidentifier;
 
-	MemSet(&stream, 0, sizeof(stream));
-
 	/*
 	 * Connect in replication mode to the server
 	 */
diff --git a/src/bin/pg_basebackup/walmethods.c b/src/bin/pg_basebackup/walmethods.c
index ef4c11277a..e90aa0ba37 100644
--- a/src/bin/pg_basebackup/walmethods.c
+++ b/src/bin/pg_basebackup/walmethods.c
@@ -1111,9 +1111,8 @@ tar_close(Walfile f, WalCloseMethod method)
 	padding = tarPaddingBytesRequired(filesize);
 	if (padding)
 	{
-		char		zerobuf[TAR_BLOCK_SIZE];
+		char		zerobuf[TAR_BLOCK_SIZE] = {0};
 
-		MemSet(zerobuf, 0, padding);
 		if (tar_write(f, zerobuf, padding) != padding)
 			return -1;
 	}
@@ -1222,7 +1221,7 @@ tar_existsfile(const char *pathname)
 static bool
 tar_finish(void)
 {
-	char		zerobuf[1024];
+	char		zerobuf[1024] = {0};
 
 	tar_clear_error();
 
@@ -1233,7 +1232,6 @@ tar_finish(void)
 	}
 
 	/* A tarfile always ends with two empty blocks */
-	MemSet(zerobuf, 0, sizeof(zerobuf));
 	if (tar_data->compression_algorithm == PG_COMPRESSION_NONE)
 	{
 		errno = 0;
diff --git a/src/common/ip.c b/src/common/ip.c
index cd73d49679..267103efb9 100644
--- a/src/common/ip.c
+++ b/src/common/ip.c
@@ -165,14 +165,12 @@ static int
 getaddrinfo_unix(const char *path, const struct addrinfo *hintsp,
 				 struct addrinfo **result)
 {
-	struct addrinfo hints;
+	struct addrinfo hints = {0};
 	struct addrinfo *aip;
 	struct sockaddr_un *unp;
 
 	*result = NULL;
 
-	MemSet(&hints, 0, sizeof(hints));
-
 	if (strlen(path) >= sizeof(unp->sun_path))
 		return EAI_FAIL;
 
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index dc49387d6c..0362500386 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -2325,7 +2325,7 @@ keep_going:						/* We will come back to here until there is
 	if (conn->try_next_host)
 	{
 		pg_conn_host *ch;
-		struct addrinfo hint;
+		struct addrinfo hint = {0};
 		int			thisport;
 		int			ret;
 		char		portstr[MAXPGPATH];
@@ -2364,7 +2364,6 @@ keep_going:						/* We will come back to here until there is
 		ch = &conn->connhost[conn->whichhost];
 
 		/* Initialize hint structure */
-		MemSet(&hint, 0, sizeof(hint));
 		hint.ai_socktype = SOCK_STREAM;
 		conn->addrlist_family = hint.ai_family = AF_UNSPEC;
 
diff --git a/src/pl/plperl/plperl.c b/src/pl/plperl/plperl.c
index edb93ec1c4..6272e093c5 100644
--- a/src/pl/plperl/plperl.c
+++ b/src/pl/plperl/plperl.c
@@ -1841,10 +1841,9 @@ plperl_call_handler(PG_FUNCTION_ARGS)
 	Datum		retval = (Datum) 0;
 	plperl_call_data *volatile save_call_data = current_call_data;
 	plperl_interp_desc *volatile oldinterp = plperl_active_interp;
-	plperl_call_data this_call_data;
+	plperl_call_data this_call_data = {0};
 
 	/* Initialize current-call status record */
-	MemSet(&this_call_data, 0, sizeof(this_call_data));
 	this_call_data.fcinfo = fcinfo;
 
 	PG_TRY();
@@ -1882,16 +1881,13 @@ plperl_inline_handler(PG_FUNCTION_ARGS)
 {
 	LOCAL_FCINFO(fake_fcinfo, 0);
 	InlineCodeBlock *codeblock = (InlineCodeBlock *) PG_GETARG_POINTER(0);
-	FmgrInfo	flinfo;
-	plperl_proc_desc desc;
+	FmgrInfo	flinfo = {0};
+	plperl_proc_desc desc = {0};
 	plperl_call_data *volatile save_call_data = current_call_data;
 	plperl_interp_desc *volatile oldinterp = plperl_active_interp;
-	plperl_call_data this_call_data;
+	plperl_call_data this_call_data = {0};
 	ErrorContextCallback pl_error_context;
 
-	/* Initialize current-call status record */
-	MemSet(&this_call_data, 0, sizeof(this_call_data));
-
 	/* Set up a callback for error reporting */
 	pl_error_context.callback = plperl_inline_callback;
 	pl_error_context.previous = error_context_stack;
@@ -1904,8 +1900,6 @@ plperl_inline_handler(PG_FUNCTION_ARGS)
 	 * with no arguments passed, and a result type of VOID.
 	 */
 	MemSet(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
-	MemSet(&flinfo, 0, sizeof(flinfo));
-	MemSet(&desc, 0, sizeof(desc));
 	fake_fcinfo->flinfo = &flinfo;
 	flinfo.fn_oid = InvalidOid;
 	flinfo.fn_mcxt = CurrentMemoryContext;
diff --git a/src/pl/plpgsql/src/pl_handler.c b/src/pl/plpgsql/src/pl_handler.c
index 190d286f1c..1f8c9edfa8 100644
--- a/src/pl/plpgsql/src/pl_handler.c
+++ b/src/pl/plpgsql/src/pl_handler.c
@@ -317,7 +317,7 @@ plpgsql_inline_handler(PG_FUNCTION_ARGS)
 	LOCAL_FCINFO(fake_fcinfo, 0);
 	InlineCodeBlock *codeblock = castNode(InlineCodeBlock, DatumGetPointer(PG_GETARG_DATUM(0)));
 	PLpgSQL_function *func;
-	FmgrInfo	flinfo;
+	FmgrInfo	flinfo = {0};
 	EState	   *simple_eval_estate;
 	ResourceOwner simple_eval_resowner;
 	Datum		retval;
@@ -341,7 +341,6 @@ plpgsql_inline_handler(PG_FUNCTION_ARGS)
 	 * with no arguments passed.
 	 */
 	MemSet(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
-	MemSet(&flinfo, 0, sizeof(flinfo));
 	fake_fcinfo->flinfo = &flinfo;
 	flinfo.fn_oid = InvalidOid;
 	flinfo.fn_mcxt = CurrentMemoryContext;
@@ -502,10 +501,10 @@ plpgsql_validator(PG_FUNCTION_ARGS)
 	if (check_function_bodies)
 	{
 		LOCAL_FCINFO(fake_fcinfo, 0);
-		FmgrInfo	flinfo;
+		FmgrInfo	flinfo = {0};
 		int			rc;
-		TriggerData trigdata;
-		EventTriggerData etrigdata;
+		TriggerData trigdata = {0};
+		EventTriggerData etrigdata = {0};
 
 		/*
 		 * Connect to SPI manager (is this needed for compilation?)
@@ -518,19 +517,16 @@ plpgsql_validator(PG_FUNCTION_ARGS)
 		 * plpgsql_compile().
 		 */
 		MemSet(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
-		MemSet(&flinfo, 0, sizeof(flinfo));
 		fake_fcinfo->flinfo = &flinfo;
 		flinfo.fn_oid = funcoid;
 		flinfo.fn_mcxt = CurrentMemoryContext;
 		if (is_dml_trigger)
 		{
-			MemSet(&trigdata, 0, sizeof(trigdata));
 			trigdata.type = T_TriggerData;
 			fake_fcinfo->context = (Node *) &trigdata;
 		}
 		else if (is_event_trigger)
 		{
-			MemSet(&etrigdata, 0, sizeof(etrigdata));
 			etrigdata.type = T_EventTriggerData;
 			fake_fcinfo->context = (Node *) &etrigdata;
 		}
diff --git a/src/pl/plpython/plpy_main.c b/src/pl/plpython/plpy_main.c
index 0bce106495..1df2dd536c 100644
--- a/src/pl/plpython/plpy_main.c
+++ b/src/pl/plpython/plpy_main.c
@@ -266,8 +266,8 @@ plpython3_inline_handler(PG_FUNCTION_ARGS)
 {
 	LOCAL_FCINFO(fake_fcinfo, 0);
 	InlineCodeBlock *codeblock = (InlineCodeBlock *) DatumGetPointer(PG_GETARG_DATUM(0));
-	FmgrInfo	flinfo;
-	PLyProcedure proc;
+	FmgrInfo	flinfo = {0};
+	PLyProcedure proc = {0};
 	PLyExecutionContext *exec_ctx;
 	ErrorContextCallback plerrcontext;
 
@@ -278,12 +278,10 @@ plpython3_inline_handler(PG_FUNCTION_ARGS)
 		elog(ERROR, "SPI_connect failed");
 
 	MemSet(fcinfo, 0, SizeForFunctionCallInfo(0));
-	MemSet(&flinfo, 0, sizeof(flinfo));
 	fake_fcinfo->flinfo = &flinfo;
 	flinfo.fn_oid = InvalidOid;
 	flinfo.fn_mcxt = CurrentMemoryContext;
 
-	MemSet(&proc, 0, sizeof(PLyProcedure));
 	proc.mcxt = AllocSetContextCreate(TopMemoryContext,
 									  "__plpython_inline_block",
 									  ALLOCSET_DEFAULT_SIZES);
diff --git a/src/port/snprintf.c b/src/port/snprintf.c
index abb1c59770..d4cf368075 100644
--- a/src/port/snprintf.c
+++ b/src/port/snprintf.c
@@ -756,12 +756,10 @@ find_arguments(const char *format, va_list args,
 	int			longflag;
 	int			fmtpos;
 	int			i;
-	int			last_dollar;
-	PrintfArgType argtypes[PG_NL_ARGMAX + 1];
 
 	/* Initialize to "no dollar arguments known" */
-	last_dollar = 0;
-	MemSet(argtypes, 0, sizeof(argtypes));
+	int			last_dollar = 0;
+	PrintfArgType argtypes[PG_NL_ARGMAX + 1] = {0};
 
 	/*
 	 * This loop must accept the same format strings as the one in dopr().
diff --git a/src/test/modules/test_predtest/test_predtest.c b/src/test/modules/test_predtest/test_predtest.c
index 3b19e0eadc..2ce88cb624 100644
--- a/src/test/modules/test_predtest/test_predtest.c
+++ b/src/test/modules/test_predtest/test_predtest.c
@@ -50,7 +50,7 @@ test_predtest(PG_FUNCTION_ARGS)
 				strong_refuted_by,
 				weak_refuted_by;
 	Datum		values[8];
-	bool		nulls[8];
+	bool		nulls[8] = {0};
 	int			i;
 
 	/* We use SPI to parse, plan, and execute the test query */
@@ -204,7 +204,6 @@ test_predtest(PG_FUNCTION_ARGS)
 					   "w_r_holds", BOOLOID, -1, 0);
 	tupdesc = BlessTupleDesc(tupdesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = BoolGetDatum(strong_implied_by);
 	values[1] = BoolGetDatum(weak_implied_by);
 	values[2] = BoolGetDatum(strong_refuted_by);
diff --git a/src/test/regress/regress.c b/src/test/regress/regress.c
index ba3532a51e..b88d70b6fc 100644
--- a/src/test/regress/regress.c
+++ b/src/test/regress/regress.c
@@ -1110,7 +1110,7 @@ test_enc_conversion(PG_FUNCTION_ARGS)
 	int			convertedbytes;
 	int			dstlen;
 	Datum		values[2];
-	bool		nulls[2];
+	bool		nulls[2] = {0};
 	HeapTuple	tuple;
 
 	if (src_encoding < 0)
@@ -1199,7 +1199,6 @@ test_enc_conversion(PG_FUNCTION_ARGS)
 		pfree(dst);
 	}
 
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = Int32GetDatum(convertedbytes);
 	values[1] = PointerGetDatum(retval);
 	tuple = heap_form_tuple(tupdesc, values, nulls);

diff --git a/contrib/pageinspect/heapfuncs.c b/contrib/pageinspect/heapfuncs.c
index 2ff70405cf..01ce9014ec 100644
--- a/contrib/pageinspect/heapfuncs.c
+++ b/contrib/pageinspect/heapfuncs.c
@@ -180,8 +180,8 @@ heap_page_items(PG_FUNCTION_ARGS)
 		HeapTuple	resultTuple;
 		Datum		result;
 		ItemId		id;
-		Datum		values[14];
-		bool		nulls[14];
+		Datum		values[14] = {0};
+		bool		nulls[14] = {0};
 		uint16		lp_offset;
 		uint16		lp_flags;
 		uint16		lp_len;
diff --git a/contrib/pg_trgm/trgm_regexp.c b/contrib/pg_trgm/trgm_regexp.c
index 58d32ba946..79c925b8dd 100644
--- a/contrib/pg_trgm/trgm_regexp.c
+++ b/contrib/pg_trgm/trgm_regexp.c
@@ -905,7 +905,7 @@ static void
 transformGraph(TrgmNFA *trgmNFA)
 {
 	HASHCTL		hashCtl;
-	TrgmStateKey initkey;
+	TrgmStateKey initkey = {0};
 	TrgmState  *initstate;
 	ListCell   *lc;
 
@@ -926,7 +926,6 @@ transformGraph(TrgmNFA *trgmNFA)
 	trgmNFA->nstates = 0;
 
 	/* Create initial state: ambiguous prefix, NFA's initial state */
-	MemSet(&initkey, 0, sizeof(initkey));
 	initkey.prefix.colors[0] = COLOR_UNKNOWN;
 	initkey.prefix.colors[1] = COLOR_UNKNOWN;
 	initkey.nstate = pg_reg_getinitialstate(trgmNFA->regex);
@@ -1019,17 +1018,11 @@ static void
 addKey(TrgmNFA *trgmNFA, TrgmState *state, TrgmStateKey *key)
 {
 	regex_arc_t *arcs;
-	TrgmStateKey destKey;
+	TrgmStateKey destKey = {0};
 	ListCell   *cell;
 	int			i,
 				arcsCount;
 
-	/*
-	 * Ensure any pad bytes in destKey are zero, since it may get used as a
-	 * hashtable key by getState.
-	 */
-	MemSet(&destKey, 0, sizeof(destKey));
-
 	/*
 	 * Compare key to each existing enter key of the state to check for
 	 * redundancy.  We can drop either old key(s) or the new key if we find
@@ -1199,18 +1192,12 @@ addKeyToQueue(TrgmNFA *trgmNFA, TrgmStateKey *key)
 static void
 addArcs(TrgmNFA *trgmNFA, TrgmState *state)
 {
-	TrgmStateKey destKey;
+	TrgmStateKey destKey = {0};
 	ListCell   *cell;
 	regex_arc_t *arcs;
 	int			arcsCount,
 				i;
 
-	/*
-	 * Ensure any pad bytes in destKey are zero, since it may get used as a
-	 * hashtable key by getState.
-	 */
-	MemSet(&destKey, 0, sizeof(destKey));
-
 	/*
 	 * Iterate over enter keys associated with this expanded-graph state. This
 	 * includes both the state's own stateKey, and any enter keys we added to
diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c
index 048db542d3..ee5b1b246f 100644
--- a/contrib/postgres_fdw/postgres_fdw.c
+++ b/contrib/postgres_fdw/postgres_fdw.c
@@ -3307,7 +3307,7 @@ estimate_path_cost_size(PlannerInfo *root,
 		{
 			RelOptInfo *outerrel = fpinfo->outerrel;
 			PgFdwRelationInfo *ofpinfo;
-			AggClauseCosts aggcosts;
+			AggClauseCosts aggcosts = {0};
 			double		input_rows;
 			int			numGroupCols;
 			double		numGroups = 1;
@@ -3331,7 +3331,6 @@ estimate_path_cost_size(PlannerInfo *root,
 			input_rows = ofpinfo->rows;
 
 			/* Collect statistics about aggregates for estimating costs. */
-			MemSet(&aggcosts, 0, sizeof(AggClauseCosts));
 			if (root->parse->hasAggs)
 			{
 				get_agg_clause_costs(root, AGGSPLIT_SIMPLE, &aggcosts);
diff --git a/contrib/tablefunc/tablefunc.c b/contrib/tablefunc/tablefunc.c
index e308228bde..6452111e19 100644
--- a/contrib/tablefunc/tablefunc.c
+++ b/contrib/tablefunc/tablefunc.c
@@ -127,9 +127,8 @@ typedef struct crosstab_cat_desc
 
 #define crosstab_HashTableLookup(HASHTAB, CATNAME, CATDESC) \
 do { \
-	crosstab_HashEnt *hentry; char key[MAX_CATNAME_LEN]; \
+	crosstab_HashEnt *hentry; char key[MAX_CATNAME_LEN] = {0}; \
 	\
-	MemSet(key, 0, MAX_CATNAME_LEN); \
 	snprintf(key, MAX_CATNAME_LEN - 1, "%s", CATNAME); \
 	hentry = (crosstab_HashEnt*) hash_search(HASHTAB, \
 										 key, HASH_FIND, NULL); \
@@ -141,9 +140,8 @@ do { \
 
 #define crosstab_HashTableInsert(HASHTAB, CATDESC) \
 do { \
-	crosstab_HashEnt *hentry; bool found; char key[MAX_CATNAME_LEN]; \
+	crosstab_HashEnt *hentry; bool found; char key[MAX_CATNAME_LEN] = {0}; \
 	\
-	MemSet(key, 0, MAX_CATNAME_LEN); \
 	snprintf(key, MAX_CATNAME_LEN - 1, "%s", CATDESC->catname); \
 	hentry = (crosstab_HashEnt*) hash_search(HASHTAB, \
 										 key, HASH_ENTER, &found); \
diff --git a/src/backend/access/nbtree/nbtpage.c b/src/backend/access/nbtree/nbtpage.c
index 8b96708b3e..f872076d52 100644
--- a/src/backend/access/nbtree/nbtpage.c
+++ b/src/backend/access/nbtree/nbtpage.c
@@ -2096,7 +2096,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack)
 	OffsetNumber poffset;
 	OffsetNumber nextoffset;
 	IndexTuple	itup;
-	IndexTupleData trunctuple;
+	IndexTupleData trunctuple = {0};
 
 	page = BufferGetPage(leafbuf);
 	opaque = BTPageGetOpaque(page);
@@ -2220,7 +2220,6 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack)
 	opaque->btpo_flags |= BTP_HALF_DEAD;
 
 	Assert(PageGetMaxOffsetNumber(page) == P_HIKEY);
-	MemSet(&trunctuple, 0, sizeof(IndexTupleData));
 	trunctuple.t_info = sizeof(IndexTupleData);
 	if (topparent != leafblkno)
 		BTreeTupleSetTopParent(&trunctuple, topparent);
diff --git a/src/backend/access/nbtree/nbtxlog.c b/src/backend/access/nbtree/nbtxlog.c
index ad489e33b3..14fe2d76c4 100644
--- a/src/backend/access/nbtree/nbtxlog.c
+++ b/src/backend/access/nbtree/nbtxlog.c
@@ -717,7 +717,7 @@ btree_xlog_mark_page_halfdead(uint8 info, XLogReaderState *record)
 	Buffer		buffer;
 	Page		page;
 	BTPageOpaque pageop;
-	IndexTupleData trunctuple;
+	IndexTupleData trunctuple = {0};
 
 	/*
 	 * In normal operation, we would lock all the pages this WAL record
@@ -780,7 +780,6 @@ btree_xlog_mark_page_halfdead(uint8 info, XLogReaderState *record)
 	 * Construct a dummy high key item that points to top parent page (value
 	 * is InvalidBlockNumber when the top parent page is the leaf page itself)
 	 */
-	MemSet(&trunctuple, 0, sizeof(IndexTupleData));
 	trunctuple.t_info = sizeof(IndexTupleData);
 	BTreeTupleSetTopParent(&trunctuple, xlrec->topparent);
 
@@ -898,7 +897,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record)
 		 * we'll delete in the subtree undergoing deletion.
 		 */
 		Buffer		leafbuf;
-		IndexTupleData trunctuple;
+		IndexTupleData trunctuple = {0};
 
 		Assert(!isleaf);
 
@@ -915,7 +914,6 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record)
 		pageop->btpo_cycleid = 0;
 
 		/* Add a dummy hikey item */
-		MemSet(&trunctuple, 0, sizeof(IndexTupleData));
 		trunctuple.t_info = sizeof(IndexTupleData);
 		BTreeTupleSetTopParent(&trunctuple, xlrec->leaftopparent);
 
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 15ab8d90d4..920fcca39c 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -6287,7 +6287,7 @@ void
 CreateCheckPoint(int flags)
 {
 	bool		shutdown;
-	CheckPoint	checkPoint;
+	CheckPoint	checkPoint = {0};
 	XLogRecPtr	recptr;
 	XLogSegNo	_logSegNo;
 	XLogCtlInsert *Insert = &XLogCtl->Insert;
@@ -6344,7 +6344,6 @@ CreateCheckPoint(int flags)
 	}
 
 	/* Begin filling in the checkpoint WAL record */
-	MemSet(&checkPoint, 0, sizeof(checkPoint));
 	checkPoint.time = (pg_time_t) time(NULL);
 
 	/*
diff --git a/src/backend/commands/copyfromparse.c b/src/backend/commands/copyfromparse.c
index 57813b3458..cef0f2c279 100644
--- a/src/backend/commands/copyfromparse.c
+++ b/src/backend/commands/copyfromparse.c
@@ -869,7 +869,7 @@ NextCopyFrom(CopyFromState cstate, ExprContext *econtext,
 
 	/* Initialize all values for row to NULL */
 	MemSet(values, 0, num_phys_attrs * sizeof(Datum));
-	MemSet(nulls, true, num_phys_attrs * sizeof(bool));
+	memset(nulls, true, num_phys_attrs * sizeof(bool));
 
 	if (!cstate->opts.binary)
 	{
diff --git a/src/backend/libpq/auth.c b/src/backend/libpq/auth.c
index 2d9ab7edce..53fb7ca628 100644
--- a/src/backend/libpq/auth.c
+++ b/src/backend/libpq/auth.c
@@ -3022,7 +3022,7 @@ PerformRadiusTransaction(const char *server, const char *secret, const char *por
 	struct sockaddr_in localaddr;
 	struct sockaddr_in remoteaddr;
 #endif
-	struct addrinfo hint;
+	struct addrinfo hint = {0};
 	struct addrinfo *serveraddrs;
 	int			port;
 	socklen_t	addrsize;
@@ -3038,7 +3038,6 @@ PerformRadiusTransaction(const char *server, const char *secret, const char *por
 	if (identifier == NULL)
 		identifier = "postgresql";
 
-	MemSet(&hint, 0, sizeof(hint));
 	hint.ai_socktype = SOCK_DGRAM;
 	hint.ai_family = AF_UNSPEC;
 	port = atoi(portstr);
diff --git a/src/backend/libpq/pqcomm.c b/src/backend/libpq/pqcomm.c
index 75392a8bb7..803d166640 100644
--- a/src/backend/libpq/pqcomm.c
+++ b/src/backend/libpq/pqcomm.c
@@ -331,7 +331,7 @@ StreamServerPort(int family, const char *hostName, unsigned short portNumber,
 	char	   *service;
 	struct addrinfo *addrs = NULL,
 			   *addr;
-	struct addrinfo hint;
+	struct addrinfo hint = {0};
 	int			listen_index = 0;
 	int			added = 0;
 
@@ -343,7 +343,6 @@ StreamServerPort(int family, const char *hostName, unsigned short portNumber,
 #endif
 
 	/* Initialize hint structure */
-	MemSet(&hint, 0, sizeof(hint));
 	hint.ai_family = family;
 	hint.ai_flags = AI_PASSIVE;
 	hint.ai_socktype = SOCK_STREAM;
diff --git a/src/backend/optimizer/path/indxpath.c b/src/backend/optimizer/path/indxpath.c
index 7d176e7b00..e23995eb4f 100644
--- a/src/backend/optimizer/path/indxpath.c
+++ b/src/backend/optimizer/path/indxpath.c
@@ -608,7 +608,7 @@ get_join_index_paths(PlannerInfo *root, RelOptInfo *rel,
 					 Relids relids,
 					 List **considered_relids)
 {
-	IndexClauseSet clauseset;
+	IndexClauseSet clauseset = {0};
 	int			indexcol;
 
 	/* If we already considered this relids set, don't repeat the work */
@@ -616,8 +616,6 @@ get_join_index_paths(PlannerInfo *root, RelOptInfo *rel,
 		return;
 
 	/* Identify indexclauses usable with this relids set */
-	MemSet(&clauseset, 0, sizeof(clauseset));
-
 	for (indexcol = 0; indexcol < index->nkeycolumns; indexcol++)
 	{
 		ListCell   *lc;
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c
index 06ad856eac..77cbe681e5 100644
--- a/src/backend/optimizer/plan/planner.c
+++ b/src/backend/optimizer/plan/planner.c
@@ -3350,9 +3350,8 @@ create_grouping_paths(PlannerInfo *root,
 	Query	   *parse = root->parse;
 	RelOptInfo *grouped_rel;
 	RelOptInfo *partially_grouped_rel;
-	AggClauseCosts agg_costs;
+	AggClauseCosts agg_costs = {0};
 
-	MemSet(&agg_costs, 0, sizeof(AggClauseCosts));
 	get_agg_clause_costs(root, AGGSPLIT_SIMPLE, &agg_costs);
 
 	/*
@@ -5908,16 +5907,14 @@ expression_planner_with_deps(Expr *expr,
 							 List **invalItems)
 {
 	Node	   *result;
-	PlannerGlobal glob;
-	PlannerInfo root;
+	PlannerGlobal glob = {0};
+	PlannerInfo root = {0};
 
 	/* Make up dummy planner state so we can use setrefs machinery */
-	MemSet(&glob, 0, sizeof(glob));
 	glob.type = T_PlannerGlobal;
 	glob.relationOids = NIL;
 	glob.invalItems = NIL;
 
-	MemSet(&root, 0, sizeof(root));
 	root.type = T_PlannerInfo;
 	root.glob = &glob;
 
diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c
index 1cb0abdbc1..311583acde 100644
--- a/src/backend/optimizer/plan/setrefs.c
+++ b/src/backend/optimizer/plan/setrefs.c
@@ -3292,18 +3292,16 @@ extract_query_dependencies(Node *query,
 						   List **invalItems,
 						   bool *hasRowSecurity)
 {
-	PlannerGlobal glob;
-	PlannerInfo root;
+	PlannerGlobal glob = {0};
+	PlannerInfo root = {0};
 
 	/* Make up dummy planner state so we can use this module's machinery */
-	MemSet(&glob, 0, sizeof(glob));
 	glob.type = T_PlannerGlobal;
 	glob.relationOids = NIL;
 	glob.invalItems = NIL;
 	/* Hack: we use glob.dependsOnRole to collect hasRowSecurity flags */
 	glob.dependsOnRole = false;
 
-	MemSet(&root, 0, sizeof(root));
 	root.type = T_PlannerInfo;
 	root.glob = &glob;
 
diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c
index 16a0fe59e2..d69cb58b6a 100644
--- a/src/backend/parser/parse_target.c
+++ b/src/backend/parser/parse_target.c
@@ -1648,10 +1648,9 @@ expandRecordVariable(ParseState *pstate, Var *var, int levelsup)
 					 * in step with varlevelsup in the CTE; furthermore it
 					 * could be an outer CTE.
 					 */
-					ParseState	mypstate;
+					ParseState	mypstate = {0};
 					Index		levelsup;
 
-					MemSet(&mypstate, 0, sizeof(mypstate));
 					/* this loop must work, since GetCTEForRTE did */
 					for (levelsup = 0;
 						 levelsup < rte->ctelevelsup + netlevelsup;
diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c
index 3a86786cc3..c4b9a14a8a 100644
--- a/src/backend/replication/walsender.c
+++ b/src/backend/replication/walsender.c
@@ -3532,7 +3532,7 @@ pg_stat_get_wal_senders(PG_FUNCTION_ARGS)
 			 * can see details. Other users only get the pid value to know
 			 * it's a walsender, but no details.
 			 */
-			MemSet(&nulls[1], true, PG_STAT_GET_WAL_SENDERS_COLS - 1);
+			memset(&nulls[1], true, PG_STAT_GET_WAL_SENDERS_COLS - 1);
 		}
 		else
 		{
diff --git a/src/backend/storage/lmgr/lock.c b/src/backend/storage/lmgr/lock.c
index 5f5803f681..ae6a1b1116 100644
--- a/src/backend/storage/lmgr/lock.c
+++ b/src/backend/storage/lmgr/lock.c
@@ -597,13 +597,12 @@ DoLockModesConflict(LOCKMODE mode1, LOCKMODE mode2)
 bool
 LockHeldByMe(const LOCKTAG *locktag, LOCKMODE lockmode)
 {
-	LOCALLOCKTAG localtag;
+	LOCALLOCKTAG localtag = {0};
 	LOCALLOCK  *locallock;
 
 	/*
 	 * See if there is a LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
@@ -635,7 +634,7 @@ LockHasWaiters(const LOCKTAG *locktag, LOCKMODE lockmode, bool sessionLock)
 {
 	LOCKMETHODID lockmethodid = locktag->locktag_lockmethodid;
 	LockMethod	lockMethodTable;
-	LOCALLOCKTAG localtag;
+	LOCALLOCKTAG localtag = {0};
 	LOCALLOCK  *locallock;
 	LOCK	   *lock;
 	PROCLOCK   *proclock;
@@ -658,7 +657,6 @@ LockHasWaiters(const LOCKTAG *locktag, LOCKMODE lockmode, bool sessionLock)
 	/*
 	 * Find the LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
@@ -777,7 +775,7 @@ LockAcquireExtended(const LOCKTAG *locktag,
 {
 	LOCKMETHODID lockmethodid = locktag->locktag_lockmethodid;
 	LockMethod	lockMethodTable;
-	LOCALLOCKTAG localtag;
+	LOCALLOCKTAG localtag = {0};
 	LOCALLOCK  *locallock;
 	LOCK	   *lock;
 	PROCLOCK   *proclock;
@@ -820,7 +818,6 @@ LockAcquireExtended(const LOCKTAG *locktag,
 	/*
 	 * Find or create a LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
@@ -1976,7 +1973,7 @@ LockRelease(const LOCKTAG *locktag, LOCKMODE lockmode, bool sessionLock)
 {
 	LOCKMETHODID lockmethodid = locktag->locktag_lockmethodid;
 	LockMethod	lockMethodTable;
-	LOCALLOCKTAG localtag;
+	LOCALLOCKTAG localtag = {0};
 	LOCALLOCK  *locallock;
 	LOCK	   *lock;
 	PROCLOCK   *proclock;
@@ -1999,7 +1996,6 @@ LockRelease(const LOCKTAG *locktag, LOCKMODE lockmode, bool sessionLock)
 	/*
 	 * Find the LOCALLOCK entry for this lock and lockmode
 	 */
-	MemSet(&localtag, 0, sizeof(localtag)); /* must clear padding */
 	localtag.lock = *locktag;
 	localtag.mode = lockmode;
 
diff --git a/src/backend/storage/lmgr/lwlock.c b/src/backend/storage/lmgr/lwlock.c
index 38317edaf9..ce5e5c073f 100644
--- a/src/backend/storage/lmgr/lwlock.c
+++ b/src/backend/storage/lmgr/lwlock.c
@@ -384,7 +384,7 @@ print_lwlock_stats(int code, Datum arg)
 static lwlock_stats *
 get_lwlock_stats_entry(LWLock *lock)
 {
-	lwlock_stats_key key;
+	lwlock_stats_key key = {0};
 	lwlock_stats *lwstats;
 	bool		found;
 
@@ -397,7 +397,6 @@ get_lwlock_stats_entry(LWLock *lock)
 		return &lwlock_stats_dummy;
 
 	/* Fetch or create the entry. */
-	MemSet(&key, 0, sizeof(key));
 	key.tranche = lock->tranche;
 	key.instance = lock;
 	lwstats = hash_search(lwlock_stats_htab, &key, HASH_ENTER, &found);
diff --git a/src/backend/utils/adt/datetime.c b/src/backend/utils/adt/datetime.c
index 43fff50d49..8976f4e9f7 100644
--- a/src/backend/utils/adt/datetime.c
+++ b/src/backend/utils/adt/datetime.c
@@ -4930,7 +4930,7 @@ pg_timezone_abbrevs(PG_FUNCTION_ARGS)
 	int			gmtoffset;
 	bool		is_dst;
 	unsigned char *p;
-	struct pg_itm_in itm_in;
+	struct pg_itm_in itm_in = {0};
 	Interval   *resInterval;
 
 	/* stuff done only on the first call of the function */
@@ -5022,7 +5022,6 @@ pg_timezone_abbrevs(PG_FUNCTION_ARGS)
 	values[0] = CStringGetTextDatum(buffer);
 
 	/* Convert offset (in seconds) to an interval; can't overflow */
-	MemSet(&itm_in, 0, sizeof(struct pg_itm_in));
 	itm_in.tm_usec = (int64) gmtoffset * USECS_PER_SEC;
 	resInterval = (Interval *) palloc(sizeof(Interval));
 	(void) itmin2interval(&itm_in, resInterval);
@@ -5055,7 +5054,7 @@ pg_timezone_names(PG_FUNCTION_ARGS)
 	fsec_t		fsec;
 	const char *tzn;
 	Interval   *resInterval;
-	struct pg_itm_in itm_in;
+	struct pg_itm_in itm_in = {0};
 
 	SetSingleFuncCall(fcinfo, 0);
 
@@ -5090,7 +5089,6 @@ pg_timezone_names(PG_FUNCTION_ARGS)
 		values[1] = CStringGetTextDatum(tzn ? tzn : "");
 
 		/* Convert tzoff to an interval; can't overflow */
-		MemSet(&itm_in, 0, sizeof(struct pg_itm_in));
 		itm_in.tm_usec = (int64) -tzoff * USECS_PER_SEC;
 		resInterval = (Interval *) palloc(sizeof(Interval));
 		(void) itmin2interval(&itm_in, resInterval);
diff --git a/src/backend/utils/adt/formatting.c b/src/backend/utils/adt/formatting.c
index 6f8734a947..b48fa2a96a 100644
--- a/src/backend/utils/adt/formatting.c
+++ b/src/backend/utils/adt/formatting.c
@@ -5613,13 +5613,11 @@ NUM_processor(FormatNode *node, NUMDesc *Num, char *inout,
 			  int sign, bool is_to_char, Oid collid)
 {
 	FormatNode *n;
-	NUMProc		_Np,
+	NUMProc		_Np = {0},
 			   *Np = &_Np;
 	const char *pattern;
 	int			pattern_len;
 
-	MemSet(Np, 0, sizeof(NUMProc));
-
 	Np->Num = Num;
 	Np->is_to_char = is_to_char;
 	Np->number = number;
diff --git a/src/backend/utils/adt/tsrank.c b/src/backend/utils/adt/tsrank.c
index 3858fc5928..7d78219b62 100644
--- a/src/backend/utils/adt/tsrank.c
+++ b/src/backend/utils/adt/tsrank.c
@@ -853,7 +853,7 @@ calc_rank_cd(const float4 *arrdata, TSVector txt, TSQuery query, int method)
 	int			len,
 				i,
 				doclen = 0;
-	CoverExt	ext;
+	CoverExt	ext = {0};
 	double		Wdoc = 0.0;
 	double		invws[lengthof(weights)];
 	double		SumDist = 0.0,
@@ -883,7 +883,6 @@ calc_rank_cd(const float4 *arrdata, TSVector txt, TSQuery query, int method)
 		return 0.0;
 	}
 
-	MemSet(&ext, 0, sizeof(CoverExt));
 	while (Cover(doc, doclen, &qr, &ext))
 	{
 		double		Cpos = 0.0;
diff --git a/src/backend/utils/cache/relfilenumbermap.c b/src/backend/utils/cache/relfilenumbermap.c
index c4245d5ccd..71d415e04b 100644
--- a/src/backend/utils/cache/relfilenumbermap.c
+++ b/src/backend/utils/cache/relfilenumbermap.c
@@ -137,7 +137,7 @@ InitializeRelfilenumberMap(void)
 Oid
 RelidByRelfilenumber(Oid reltablespace, RelFileNumber relfilenumber)
 {
-	RelfilenumberMapKey key;
+	RelfilenumberMapKey key = {0};
 	RelfilenumberMapEntry *entry;
 	bool		found;
 	SysScanDesc scandesc;
@@ -153,7 +153,6 @@ RelidByRelfilenumber(Oid reltablespace, RelFileNumber relfilenumber)
 	if (reltablespace == MyDatabaseTableSpace)
 		reltablespace = 0;
 
-	MemSet(&key, 0, sizeof(key));
 	key.reltablespace = reltablespace;
 	key.relfilenumber = relfilenumber;
 
diff --git a/src/backend/utils/cache/ts_cache.c b/src/backend/utils/cache/ts_cache.c
index 24808dfbb1..70e88fd228 100644
--- a/src/backend/utils/cache/ts_cache.c
+++ b/src/backend/utils/cache/ts_cache.c
@@ -414,7 +414,7 @@ lookup_ts_config_cache(Oid cfgId)
 		ScanKeyData mapskey;
 		SysScanDesc mapscan;
 		HeapTuple	maptup;
-		ListDictionary maplists[MAXTOKENTYPE + 1];
+		ListDictionary maplists[MAXTOKENTYPE + 1] = {0};
 		Oid			mapdicts[MAXDICTSPERTT];
 		int			maxtokentype;
 		int			ndicts;
@@ -468,7 +468,6 @@ lookup_ts_config_cache(Oid cfgId)
 		 * see the entries in maptokentype order, and in mapseqno order for
 		 * each token type, even though we didn't explicitly ask for that.
 		 */
-		MemSet(maplists, 0, sizeof(maplists));
 		maxtokentype = 0;
 		ndicts = 0;
 
diff --git a/src/backend/utils/misc/ps_status.c b/src/backend/utils/misc/ps_status.c
index 8520ce76bb..264d0ab1df 100644
--- a/src/backend/utils/misc/ps_status.c
+++ b/src/backend/utils/misc/ps_status.c
@@ -376,7 +376,7 @@ set_ps_display(const char *activity)
 #ifdef PS_USE_CLOBBER_ARGV
 	/* pad unused memory; need only clobber remainder of old status string */
 	if (last_status_len > ps_buffer_cur_len)
-		MemSet(ps_buffer + ps_buffer_cur_len, PS_PADDING,
+		memset(ps_buffer + ps_buffer_cur_len, PS_PADDING,
 			   last_status_len - ps_buffer_cur_len);
 	last_status_len = ps_buffer_cur_len;
 #endif							/* PS_USE_CLOBBER_ARGV */
diff --git a/src/backend/utils/misc/timeout.c b/src/backend/utils/misc/timeout.c
index 6f5e08bc30..284b9153ea 100644
--- a/src/backend/utils/misc/timeout.c
+++ b/src/backend/utils/misc/timeout.c
@@ -211,13 +211,11 @@ schedule_alarm(TimestampTz now)
 {
 	if (num_active_timeouts > 0)
 	{
-		struct itimerval timeval;
+		struct itimerval timeval = {0};
 		TimestampTz nearest_timeout;
 		long		secs;
 		int			usecs;
 
-		MemSet(&timeval, 0, sizeof(struct itimerval));
-
 		/*
 		 * If we think there's a signal pending, but current time is more than
 		 * 10ms past when the signal was due, then assume that the timeout
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index dc49387d6c..0362500386 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -2325,7 +2325,7 @@ keep_going:						/* We will come back to here until there is
 	if (conn->try_next_host)
 	{
 		pg_conn_host *ch;
-		struct addrinfo hint;
+		struct addrinfo hint = {0};
 		int			thisport;
 		int			ret;
 		char		portstr[MAXPGPATH];
@@ -2364,7 +2364,6 @@ keep_going:						/* We will come back to here until there is
 		ch = &conn->connhost[conn->whichhost];
 
 		/* Initialize hint structure */
-		MemSet(&hint, 0, sizeof(hint));
 		hint.ai_socktype = SOCK_STREAM;
 		conn->addrlist_family = hint.ai_family = AF_UNSPEC;
 
diff --git a/src/pl/plperl/plperl.c b/src/pl/plperl/plperl.c
index af354a68cc..1e6cb45ad4 100644
--- a/src/pl/plperl/plperl.c
+++ b/src/pl/plperl/plperl.c
@@ -1840,10 +1840,9 @@ plperl_call_handler(PG_FUNCTION_ARGS)
 	Datum		retval = (Datum) 0;
 	plperl_call_data *volatile save_call_data = current_call_data;
 	plperl_interp_desc *volatile oldinterp = plperl_active_interp;
-	plperl_call_data this_call_data;
+	plperl_call_data this_call_data = {0};
 
 	/* Initialize current-call status record */
-	MemSet(&this_call_data, 0, sizeof(this_call_data));
 	this_call_data.fcinfo = fcinfo;
 
 	PG_TRY();
@@ -1881,16 +1880,13 @@ plperl_inline_handler(PG_FUNCTION_ARGS)
 {
 	LOCAL_FCINFO(fake_fcinfo, 0);
 	InlineCodeBlock *codeblock = (InlineCodeBlock *) PG_GETARG_POINTER(0);
-	FmgrInfo	flinfo;
-	plperl_proc_desc desc;
+	FmgrInfo	flinfo = {0};
+	plperl_proc_desc desc = {0};
 	plperl_call_data *volatile save_call_data = current_call_data;
 	plperl_interp_desc *volatile oldinterp = plperl_active_interp;
-	plperl_call_data this_call_data;
+	plperl_call_data this_call_data = {0};
 	ErrorContextCallback pl_error_context;
 
-	/* Initialize current-call status record */
-	MemSet(&this_call_data, 0, sizeof(this_call_data));
-
 	/* Set up a callback for error reporting */
 	pl_error_context.callback = plperl_inline_callback;
 	pl_error_context.previous = error_context_stack;
@@ -1903,8 +1899,6 @@ plperl_inline_handler(PG_FUNCTION_ARGS)
 	 * with no arguments passed, and a result type of VOID.
 	 */
 	MemSet(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
-	MemSet(&flinfo, 0, sizeof(flinfo));
-	MemSet(&desc, 0, sizeof(desc));
 	fake_fcinfo->flinfo = &flinfo;
 	flinfo.fn_oid = InvalidOid;
 	flinfo.fn_mcxt = CurrentMemoryContext;
diff --git a/src/pl/plpgsql/src/pl_handler.c b/src/pl/plpgsql/src/pl_handler.c
index 190d286f1c..1f8c9edfa8 100644
--- a/src/pl/plpgsql/src/pl_handler.c
+++ b/src/pl/plpgsql/src/pl_handler.c
@@ -317,7 +317,7 @@ plpgsql_inline_handler(PG_FUNCTION_ARGS)
 	LOCAL_FCINFO(fake_fcinfo, 0);
 	InlineCodeBlock *codeblock = castNode(InlineCodeBlock, DatumGetPointer(PG_GETARG_DATUM(0)));
 	PLpgSQL_function *func;
-	FmgrInfo	flinfo;
+	FmgrInfo	flinfo = {0};
 	EState	   *simple_eval_estate;
 	ResourceOwner simple_eval_resowner;
 	Datum		retval;
@@ -341,7 +341,6 @@ plpgsql_inline_handler(PG_FUNCTION_ARGS)
 	 * with no arguments passed.
 	 */
 	MemSet(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
-	MemSet(&flinfo, 0, sizeof(flinfo));
 	fake_fcinfo->flinfo = &flinfo;
 	flinfo.fn_oid = InvalidOid;
 	flinfo.fn_mcxt = CurrentMemoryContext;
@@ -502,10 +501,10 @@ plpgsql_validator(PG_FUNCTION_ARGS)
 	if (check_function_bodies)
 	{
 		LOCAL_FCINFO(fake_fcinfo, 0);
-		FmgrInfo	flinfo;
+		FmgrInfo	flinfo = {0};
 		int			rc;
-		TriggerData trigdata;
-		EventTriggerData etrigdata;
+		TriggerData trigdata = {0};
+		EventTriggerData etrigdata = {0};
 
 		/*
 		 * Connect to SPI manager (is this needed for compilation?)
@@ -518,19 +517,16 @@ plpgsql_validator(PG_FUNCTION_ARGS)
 		 * plpgsql_compile().
 		 */
 		MemSet(fake_fcinfo, 0, SizeForFunctionCallInfo(0));
-		MemSet(&flinfo, 0, sizeof(flinfo));
 		fake_fcinfo->flinfo = &flinfo;
 		flinfo.fn_oid = funcoid;
 		flinfo.fn_mcxt = CurrentMemoryContext;
 		if (is_dml_trigger)
 		{
-			MemSet(&trigdata, 0, sizeof(trigdata));
 			trigdata.type = T_TriggerData;
 			fake_fcinfo->context = (Node *) &trigdata;
 		}
 		else if (is_event_trigger)
 		{
-			MemSet(&etrigdata, 0, sizeof(etrigdata));
 			etrigdata.type = T_EventTriggerData;
 			fake_fcinfo->context = (Node *) &etrigdata;
 		}
diff --git a/src/pl/plpython/plpy_main.c b/src/pl/plpython/plpy_main.c
index a4d66f3057..40d66da28a 100644
--- a/src/pl/plpython/plpy_main.c
+++ b/src/pl/plpython/plpy_main.c
@@ -264,8 +264,8 @@ plpython3_inline_handler(PG_FUNCTION_ARGS)
 {
 	LOCAL_FCINFO(fake_fcinfo, 0);
 	InlineCodeBlock *codeblock = (InlineCodeBlock *) DatumGetPointer(PG_GETARG_DATUM(0));
-	FmgrInfo	flinfo;
-	PLyProcedure proc;
+	FmgrInfo	flinfo = {0};
+	PLyProcedure proc = {0};
 	PLyExecutionContext *exec_ctx;
 	ErrorContextCallback plerrcontext;
 
@@ -276,12 +276,10 @@ plpython3_inline_handler(PG_FUNCTION_ARGS)
 		elog(ERROR, "SPI_connect failed");
 
 	MemSet(fcinfo, 0, SizeForFunctionCallInfo(0));
-	MemSet(&flinfo, 0, sizeof(flinfo));
 	fake_fcinfo->flinfo = &flinfo;
 	flinfo.fn_oid = InvalidOid;
 	flinfo.fn_mcxt = CurrentMemoryContext;
 
-	MemSet(&proc, 0, sizeof(PLyProcedure));
 	proc.mcxt = AllocSetContextCreate(TopMemoryContext,
 									  "__plpython_inline_block",
 									  ALLOCSET_DEFAULT_SIZES);

From 25bd8af7acfd6bf2e23cdfac93828d810cfbb5b4 Mon Sep 17 00:00:00 2001
From: David Zhang <david.zhang@highgo.ca>
Date: Fri, 19 Aug 2022 14:43:01 -0700
Subject: [PATCH]     Replace many memset calls with struct initialization

    This replaces all memset() calls with struct initialization where that
    is easily and obviously possible.
---
 contrib/pageinspect/btreefuncs.c |  3 +--
 contrib/pageinspect/ginfuncs.c   | 12 +++---------
 contrib/pageinspect/gistfuncs.c  | 12 +++---------
 contrib/pageinspect/heapfuncs.c  |  4 +---
 contrib/pageinspect/rawpage.c    |  4 +---
 5 files changed, 9 insertions(+), 26 deletions(-)

diff --git a/contrib/pageinspect/btreefuncs.c b/contrib/pageinspect/btreefuncs.c
index 9375d55e14..a14d83f8cb 100644
--- a/contrib/pageinspect/btreefuncs.c
+++ b/contrib/pageinspect/btreefuncs.c
@@ -311,7 +311,7 @@ bt_page_print_tuples(struct user_args *uargs)
 	bool		rightmost = uargs->rightmost;
 	bool		ispivottuple;
 	Datum		values[9];
-	bool		nulls[9];
+	bool		nulls[9] = {0};
 	HeapTuple	tuple;
 	ItemId		id;
 	IndexTuple	itup;
@@ -331,7 +331,6 @@ bt_page_print_tuples(struct user_args *uargs)
 	itup = (IndexTuple) PageGetItem(page, id);
 
 	j = 0;
-	memset(nulls, 0, sizeof(nulls));
 	values[j++] = DatumGetInt16(offset);
 	values[j++] = ItemPointerGetDatum(&itup->t_tid);
 	values[j++] = Int32GetDatum((int) IndexTupleSize(itup));
diff --git a/contrib/pageinspect/ginfuncs.c b/contrib/pageinspect/ginfuncs.c
index 952e9d51a8..6c0183cc63 100644
--- a/contrib/pageinspect/ginfuncs.c
+++ b/contrib/pageinspect/ginfuncs.c
@@ -40,7 +40,7 @@ gin_metapage_info(PG_FUNCTION_ARGS)
 	GinMetaPageData *metadata;
 	HeapTuple	resultTuple;
 	Datum		values[10];
-	bool		nulls[10];
+	bool		nulls[10] = {0};
 
 	if (!superuser())
 		ereport(ERROR,
@@ -75,8 +75,6 @@ gin_metapage_info(PG_FUNCTION_ARGS)
 
 	metadata = GinPageGetMeta(page);
 
-	memset(nulls, 0, sizeof(nulls));
-
 	values[0] = Int64GetDatum(metadata->head);
 	values[1] = Int64GetDatum(metadata->tail);
 	values[2] = Int32GetDatum(metadata->tailFreeSize);
@@ -107,7 +105,7 @@ gin_page_opaque_info(PG_FUNCTION_ARGS)
 	GinPageOpaque opaq;
 	HeapTuple	resultTuple;
 	Datum		values[3];
-	bool		nulls[3];
+	bool		nulls[3] = {0};
 	Datum		flags[16];
 	int			nflags = 0;
 	uint16		flagbits;
@@ -162,8 +160,6 @@ gin_page_opaque_info(PG_FUNCTION_ARGS)
 		flags[nflags++] = DirectFunctionCall1(to_hex32, Int32GetDatum(flagbits));
 	}
 
-	memset(nulls, 0, sizeof(nulls));
-
 	values[0] = Int64GetDatum(opaq->rightlink);
 	values[1] = Int32GetDatum(opaq->maxoff);
 	values[2] = PointerGetDatum(construct_array_builtin(flags, nflags, TEXTOID));
@@ -255,14 +251,12 @@ gin_leafpage_items(PG_FUNCTION_ARGS)
 		HeapTuple	resultTuple;
 		Datum		result;
 		Datum		values[3];
-		bool		nulls[3];
+		bool		nulls[3] = {0};
 		int			ndecoded,
 					i;
 		ItemPointer tids;
 		Datum	   *tids_datum;
 
-		memset(nulls, 0, sizeof(nulls));
-
 		values[0] = ItemPointerGetDatum(&cur->first);
 		values[1] = UInt16GetDatum(cur->nbytes);
 
diff --git a/contrib/pageinspect/gistfuncs.c b/contrib/pageinspect/gistfuncs.c
index d0a34a3375..1e8cc88b65 100644
--- a/contrib/pageinspect/gistfuncs.c
+++ b/contrib/pageinspect/gistfuncs.c
@@ -43,7 +43,7 @@ gist_page_opaque_info(PG_FUNCTION_ARGS)
 	GISTPageOpaque opaq;
 	HeapTuple	resultTuple;
 	Datum		values[4];
-	bool		nulls[4];
+	bool		nulls[4] = {0};
 	Datum		flags[16];
 	int			nflags = 0;
 	uint16		flagbits;
@@ -99,8 +99,6 @@ gist_page_opaque_info(PG_FUNCTION_ARGS)
 		flags[nflags++] = DirectFunctionCall1(to_hex32, Int32GetDatum(flagbits));
 	}
 
-	memset(nulls, 0, sizeof(nulls));
-
 	values[0] = LSNGetDatum(PageGetLSN(page));
 	values[1] = LSNGetDatum(GistPageGetNSN(page));
 	values[2] = Int64GetDatum(opaq->rightlink);
@@ -163,7 +161,7 @@ gist_page_items_bytea(PG_FUNCTION_ARGS)
 		 offset++)
 	{
 		Datum		values[5];
-		bool		nulls[5];
+		bool		nulls[5] = {0};
 		ItemId		id;
 		IndexTuple	itup;
 		bytea	   *tuple_bytea;
@@ -177,8 +175,6 @@ gist_page_items_bytea(PG_FUNCTION_ARGS)
 		itup = (IndexTuple) PageGetItem(page, id);
 		tuple_len = IndexTupleSize(itup);
 
-		memset(nulls, 0, sizeof(nulls));
-
 		values[0] = DatumGetInt16(offset);
 		values[1] = ItemPointerGetDatum(&itup->t_tid);
 		values[2] = Int32GetDatum((int) IndexTupleSize(itup));
@@ -241,7 +237,7 @@ gist_page_items(PG_FUNCTION_ARGS)
 		 offset++)
 	{
 		Datum		values[5];
-		bool		nulls[5];
+		bool		nulls[5] = {0};
 		ItemId		id;
 		IndexTuple	itup;
 		Datum		itup_values[INDEX_MAX_KEYS];
@@ -258,8 +254,6 @@ gist_page_items(PG_FUNCTION_ARGS)
 		index_deform_tuple(itup, RelationGetDescr(indexRel),
 						   itup_values, itup_isnull);
 
-		memset(nulls, 0, sizeof(nulls));
-
 		values[0] = DatumGetInt16(offset);
 		values[1] = ItemPointerGetDatum(&itup->t_tid);
 		values[2] = Int32GetDatum((int) IndexTupleSize(itup));
diff --git a/contrib/pageinspect/heapfuncs.c b/contrib/pageinspect/heapfuncs.c
index 2ff70405cf..952f5ed57e 100644
--- a/contrib/pageinspect/heapfuncs.c
+++ b/contrib/pageinspect/heapfuncs.c
@@ -181,13 +181,11 @@ heap_page_items(PG_FUNCTION_ARGS)
 		Datum		result;
 		ItemId		id;
 		Datum		values[14];
-		bool		nulls[14];
+		bool		nulls[14] = {0};
 		uint16		lp_offset;
 		uint16		lp_flags;
 		uint16		lp_len;
 
-		memset(nulls, 0, sizeof(nulls));
-
 		/* Extract information from the line pointer */
 
 		id = PageGetItemId(page, inter_call_data->offset);
diff --git a/contrib/pageinspect/rawpage.c b/contrib/pageinspect/rawpage.c
index 90942be71e..0d1292d8f1 100644
--- a/contrib/pageinspect/rawpage.c
+++ b/contrib/pageinspect/rawpage.c
@@ -252,7 +252,7 @@ page_header(PG_FUNCTION_ARGS)
 	Datum		result;
 	HeapTuple	tuple;
 	Datum		values[9];
-	bool		nulls[9];
+	bool		nulls[9] = {0};
 
 	Page		page;
 	PageHeader	pageheader;
@@ -318,8 +318,6 @@ page_header(PG_FUNCTION_ARGS)
 
 	/* Build and return the tuple. */
 
-	memset(nulls, 0, sizeof(nulls));
-
 	tuple = heap_form_tuple(tupdesc, values, nulls);
 	result = HeapTupleGetDatum(tuple);
 
-- 
2.17.1