diff --git a/contrib/pg_trgm/trgm_regexp.c b/contrib/pg_trgm/trgm_regexp.c
index 9ee8a54a8d..b16697d09f 100644
--- a/contrib/pg_trgm/trgm_regexp.c
+++ b/contrib/pg_trgm/trgm_regexp.c
@@ -441,7 +441,7 @@ typedef struct
 struct TrgmPackedGraph
 {
 	/*
-	 * colorTrigramsCount and colorTrigramsGroups contain information about
+	 * colorTrigramsCount and colorTrigramGroups contain information about
 	 * how trigrams are grouped into color trigrams.  "colorTrigramsCount" is
 	 * the count of color trigrams and "colorTrigramGroups" contains number of
 	 * simple trigrams for each color trigram.  The array of simple trigrams
diff --git a/src/backend/libpq/be-fsstubs.c b/src/backend/libpq/be-fsstubs.c
index 68f83a9bfd..97add3f257 100644
--- a/src/backend/libpq/be-fsstubs.c
+++ b/src/backend/libpq/be-fsstubs.c
@@ -62,7 +62,7 @@
  * A non-null entry is a pointer to a LargeObjectDesc allocated in the
  * LO private memory context "fscxt".  The cookies array itself is also
  * dynamically allocated in that context.  Its current allocated size is
- * cookies_len entries, of which any unused entries will be NULL.
+ * cookies_size entries, of which any unused entries will be NULL.
  */
 static LargeObjectDesc **cookies = NULL;
 static int	cookies_size = 0;
diff --git a/src/backend/optimizer/plan/createplan.c b/src/backend/optimizer/plan/createplan.c
index 608d5adfed..12fba56285 100644
--- a/src/backend/optimizer/plan/createplan.c
+++ b/src/backend/optimizer/plan/createplan.c
@@ -3911,7 +3911,7 @@ create_foreignscan_plan(PlannerInfo *root, ForeignPath *best_path,
 }
 
 /*
- * create_custom_plan
+ * create_customscan_plan
  *
  * Transform a CustomPath into a Plan.
  */
diff --git a/src/backend/utils/adt/datetime.c b/src/backend/utils/adt/datetime.c
index e9add385ba..54ea69f7f1 100644
--- a/src/backend/utils/adt/datetime.c
+++ b/src/backend/utils/adt/datetime.c
@@ -3029,7 +3029,7 @@ DecodeSpecial(int field, char *lowtoken, int *val)
 }
 
 
-/* ClearPgTM
+/* ClearPgTm
  *
  * Zero out a pg_tm and associated fsec_t
  */
diff --git a/src/backend/utils/adt/geo_ops.c b/src/backend/utils/adt/geo_ops.c
index 373784fcc1..0fd7dae658 100644
--- a/src/backend/utils/adt/geo_ops.c
+++ b/src/backend/utils/adt/geo_ops.c
@@ -2586,7 +2586,7 @@ lseg_interpt_line(Point *result, LSEG *lseg, LINE *line)
 }
 
 /*---------------------------------------------------------------------
- *		close_
+ *		closept_
  *				Point of closest proximity between objects.
  *-------------------------------------------------------------------*/
 
diff --git a/src/backend/utils/mmgr/freepage.c b/src/backend/utils/mmgr/freepage.c
index 0c9e98973a..9a1ae13ab1 100644
--- a/src/backend/utils/mmgr/freepage.c
+++ b/src/backend/utils/mmgr/freepage.c
@@ -231,7 +231,7 @@ FreePageManagerGet(FreePageManager *fpm, Size npages, Size *first_page)
 
 	/*
 	 * FreePageManagerGetInternal may have set contiguous_pages_dirty.
-	 * Recompute contigous_pages if so.
+	 * Recompute contiguous_pages if so.
 	 */
 	FreePageManagerUpdateLargest(fpm);
 
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index 99b9fa414f..385ae90bb8 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -2031,7 +2031,6 @@ typedef struct AggState
 #define FIELDNO_AGGSTATE_ALL_PERGROUPS 34
 	AggStatePerGroup *all_pergroups;	/* array of first ->pergroups, than
 										 * ->hash_pergroup */
-	ProjectionInfo *combinedproj;	/* projection machinery */
 } AggState;
 
 /* ----------------
diff --git a/src/include/optimizer/cost.h b/src/include/optimizer/cost.h
index 9b6bdbc518..b3d0b4f6fb 100644
--- a/src/include/optimizer/cost.h
+++ b/src/include/optimizer/cost.h
@@ -86,8 +86,6 @@ extern void cost_subqueryscan(SubqueryScanPath *path, PlannerInfo *root,
 							  RelOptInfo *baserel, ParamPathInfo *param_info);
 extern void cost_functionscan(Path *path, PlannerInfo *root,
 							  RelOptInfo *baserel, ParamPathInfo *param_info);
-extern void cost_tableexprscan(Path *path, PlannerInfo *root,
-							   RelOptInfo *baserel, ParamPathInfo *param_info);
 extern void cost_valuesscan(Path *path, PlannerInfo *root,
 							RelOptInfo *baserel, ParamPathInfo *param_info);
 extern void cost_tablefuncscan(Path *path, PlannerInfo *root,
diff --git a/src/include/storage/fd.h b/src/include/storage/fd.h
index 9959258d7d..d2a8c52044 100644
--- a/src/include/storage/fd.h
+++ b/src/include/storage/fd.h
@@ -33,7 +33,7 @@
  * no way for them to share kernel file descriptors with other files.
  *
  * Likewise, use AllocateDir/FreeDir, not opendir/closedir, to allocate
- * open directories (DIR*), and OpenTransientFile/CloseTransient File for an
+ * open directories (DIR*), and OpenTransientFile/CloseTransientFile for an
  * unbuffered file descriptor.
  */
 #ifndef FD_H
diff --git a/src/include/tcop/tcopprot.h b/src/include/tcop/tcopprot.h
index 8dcfb40728..ec21f7e45c 100644
--- a/src/include/tcop/tcopprot.h
+++ b/src/include/tcop/tcopprot.h
@@ -9,11 +9,6 @@
  *
  * src/include/tcop/tcopprot.h
  *
- * OLD COMMENTS
- *	  This file was created so that other c files could get the two
- *	  function prototypes without having to include tcop.h which single
- *	  handedly includes the whole f*cking tree -- mer 5 Nov. 1991
- *
  *-------------------------------------------------------------------------
  */
 #ifndef TCOPPROT_H