diff --git a/src/backend/utils/adt/misc.c b/src/backend/utils/adt/misc.c
index aecdcd0..e8cf396 100644
--- a/src/backend/utils/adt/misc.c
+++ b/src/backend/utils/adt/misc.c
@@ -194,6 +194,27 @@ pg_reload_conf(PG_FUNCTION_ARGS)
 	PG_RETURN_BOOL(true);
 }
 
+/*
+ * Test the effects of reloading postgresql.conf file's contents
+ */
+Datum
+pg_test_reload_conf(PG_FUNCTION_ARGS)
+{
+	int nestlevel;
+
+	if (!superuser())
+		ereport(ERROR,
+				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+				 (errmsg("must be superuser to test the contents of postgresql.conf file"))));
+
+	nestlevel = NewGUCNestLevel();
+
+	ProcessConfigFile_base(PGC_SIGHUP, true);
+
+	AtEOXact_GUC(false, nestlevel);
+
+	PG_RETURN_BOOL(true);
+}
 
 /*
  * Rotate log file
diff --git a/src/backend/utils/misc/guc-file.l b/src/backend/utils/misc/guc-file.l
index d3565a5..ff23711 100644
--- a/src/backend/utils/misc/guc-file.l
+++ b/src/backend/utils/misc/guc-file.l
@@ -111,7 +111,7 @@ STRING			\'([^'\\\n]|\\.|\'\')*\'
  * If an error occurs, no values will be changed.
  */
 void
-ProcessConfigFile(GucContext context)
+ProcessConfigFile_base(GucContext context, bool testing)
 {
 	bool		error = false;
 	bool		apply = false;
@@ -288,7 +288,7 @@ ProcessConfigFile(GucContext context)
 		int		scres;
 
 		/* In SIGHUP cases in the postmaster, we want to report changes */
-		if (context == PGC_SIGHUP && !IsUnderPostmaster)
+		if ((context == PGC_SIGHUP && !IsUnderPostmaster) || testing)
 		{
 			const char *preval = GetConfigOption(item->name, true, false);
 
@@ -300,7 +300,7 @@ ProcessConfigFile(GucContext context)
 		}
 
 		scres = set_config_option(item->name, item->value,
-								  context, PGC_S_FILE,
+								  context, testing ? PGC_S_TEST : PGC_S_FILE,
 								  GUC_ACTION_SET, true, 0);
 		if (scres > 0)
 		{
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index b5be075..5c6ce06 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -4721,6 +4721,7 @@ DESCR("SP-GiST support for quad tree over range");
 DATA(insert OID = 3473 (  spg_range_quad_leaf_consistent	PGNSP PGUID 12 1 0 0 0 f f f f t f i 2 0 16 "2281 2281" _null_ _null_ _null_ _null_  spg_range_quad_leaf_consistent _null_ _null_ _null_ ));
 DESCR("SP-GiST support for quad tree over range");
 
+DATA(insert OID = 9999 ( pg_test_reload_conf			PGNSP PGUID 12 1 0 0 0 f f f f t f v 0 0 16 "" _null_ _null_ _null_ _null_ pg_test_reload_conf _null_ _null_ _null_ ));
 
 /* event triggers */
 DATA(insert OID = 3566 (  pg_event_trigger_dropped_objects		PGNSP PGUID 12 10 100 0 0 f f f f t t s 0 0 2249 "" "{26,26,23,25,25,25,25}" "{o,o,o,o,o,o,o}" "{classid, objid, objsubid, object_type, schema_name, object_name, object_identity}" _null_ pg_event_trigger_dropped_objects _null_ _null_ _null_ ));
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
index 667c58b..eb5032b 100644
--- a/src/include/utils/builtins.h
+++ b/src/include/utils/builtins.h
@@ -478,6 +478,7 @@ extern Datum current_query(PG_FUNCTION_ARGS);
 extern Datum pg_cancel_backend(PG_FUNCTION_ARGS);
 extern Datum pg_terminate_backend(PG_FUNCTION_ARGS);
 extern Datum pg_reload_conf(PG_FUNCTION_ARGS);
+extern Datum pg_test_reload_conf(PG_FUNCTION_ARGS);
 extern Datum pg_tablespace_databases(PG_FUNCTION_ARGS);
 extern Datum pg_tablespace_location(PG_FUNCTION_ARGS);
 extern Datum pg_rotate_logfile(PG_FUNCTION_ARGS);
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index d497b1f..42cdb38 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -307,7 +307,8 @@ extern void EmitWarningsOnPlaceholders(const char *className);
 extern const char *GetConfigOption(const char *name, bool missing_ok,
 				bool restrict_superuser);
 extern const char *GetConfigOptionResetString(const char *name);
-extern void ProcessConfigFile(GucContext context);
+extern void ProcessConfigFile_base(GucContext context, bool reportchanges);
+#define ProcessConfigFile(context) ProcessConfigFile_base(context, false)
 extern void InitializeGUCOptions(void);
 extern bool SelectConfigFiles(const char *userDoption, const char *progname);
 extern void ResetAllOptions(void);