Generate fmgr prototypes automatically

Gen_fmgrtab.pl creates a new file fmgrprotos.h, which contains
prototypes for all functions registered in pg_proc.h.  This avoids
having to manually maintain these prototypes across a random variety of
header files.  It also automatically enforces a correct function
signature, and since there are warnings about missing prototypes, it
will detect functions that are defined but not registered in
pg_proc.h (or otherwise used).

Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>

src/backend/access/brin/brin.c

@@ -28,6 +28,7 @@
 #include "pgstat.h"
 #include "storage/bufmgr.h"
 #include "storage/freespace.h"
+#include "utils/builtins.h"
 #include "utils/index_selfuncs.h"
 #include "utils/memutils.h"
 #include "utils/rel.h"

src/backend/access/brin/brin_inclusion.c

@@ -30,6 +30,7 @@
 #include "access/skey.h"
 #include "catalog/pg_amop.h"
 #include "catalog/pg_type.h"
+#include "utils/builtins.h"
 #include "utils/datum.h"
 #include "utils/lsyscache.h"
 #include "utils/rel.h"
@@ -76,10 +77,6 @@ typedef struct InclusionOpaque
 	FmgrInfo	strategy_procinfos[RTMaxStrategyNumber];
 } InclusionOpaque;
 
-Datum		brin_inclusion_opcinfo(PG_FUNCTION_ARGS);
-Datum		brin_inclusion_add_value(PG_FUNCTION_ARGS);
-Datum		brin_inclusion_consistent(PG_FUNCTION_ARGS);
-Datum		brin_inclusion_union(PG_FUNCTION_ARGS);
 static FmgrInfo *inclusion_get_procinfo(BrinDesc *bdesc, uint16 attno,
 					   uint16 procnum);
 static FmgrInfo *inclusion_get_strategy_procinfo(BrinDesc *bdesc, uint16 attno,

src/backend/access/brin/brin_minmax.c

@@ -16,6 +16,7 @@
 #include "access/stratnum.h"
 #include "catalog/pg_type.h"
 #include "catalog/pg_amop.h"
+#include "utils/builtins.h"
 #include "utils/datum.h"
 #include "utils/lsyscache.h"
 #include "utils/rel.h"
@@ -28,10 +29,6 @@ typedef struct MinmaxOpaque
 	FmgrInfo	strategy_procinfos[BTMaxStrategyNumber];
 } MinmaxOpaque;
 
-Datum		brin_minmax_opcinfo(PG_FUNCTION_ARGS);
-Datum		brin_minmax_add_value(PG_FUNCTION_ARGS);
-Datum		brin_minmax_consistent(PG_FUNCTION_ARGS);
-Datum		brin_minmax_union(PG_FUNCTION_ARGS);
 static FmgrInfo *minmax_get_strategy_procinfo(BrinDesc *bdesc, uint16 attno,
 							 Oid subtype, uint16 strategynum);
 

src/backend/access/gin/ginfast.c

@@ -30,6 +30,7 @@
 #include "postmaster/autovacuum.h"
 #include "storage/indexfsm.h"
 #include "storage/lmgr.h"
+#include "utils/builtins.h"
 
 /* GUC parameter */
 int			gin_pending_list_limit = 0;

src/backend/access/gist/gist.c

@@ -18,6 +18,7 @@
 #include "access/gistscan.h"
 #include "catalog/pg_collation.h"
 #include "miscadmin.h"
+#include "utils/builtins.h"
 #include "utils/index_selfuncs.h"
 #include "utils/memutils.h"
 #include "utils/rel.h"

src/backend/access/hash/hash.c

@@ -25,6 +25,7 @@
 #include "commands/vacuum.h"
 #include "miscadmin.h"
 #include "optimizer/plancat.h"
+#include "utils/builtins.h"
 #include "utils/index_selfuncs.h"
 #include "utils/rel.h"
 

src/backend/access/hash/hashfunc.c

@@ -27,7 +27,17 @@
 #include "postgres.h"
 
 #include "access/hash.h"
+#include "utils/builtins.h"
 
+/*
+ * Datatype-specific hash functions.
+ *
+ * These support both hash indexes and hash joins.
+ *
+ * NOTE: some of these are also used by catcache operations, without
+ * any direct connection to hash indexes.  Also, the common hash_any
+ * routine is also used by dynahash tables.
+ */
 
 /* Note: this is used for both "char" and boolean datatypes */
 Datum

src/backend/access/index/amapi.c

@@ -17,6 +17,7 @@
 #include "access/htup_details.h"
 #include "catalog/pg_am.h"
 #include "catalog/pg_opclass.h"
+#include "utils/builtins.h"
 #include "utils/syscache.h"
 
 

src/backend/access/nbtree/nbtree.c

@@ -28,6 +28,7 @@
 #include "storage/lmgr.h"
 #include "storage/smgr.h"
 #include "tcop/tcopprot.h"		/* pgrminclude ignore */
+#include "utils/builtins.h"
 #include "utils/index_selfuncs.h"
 #include "utils/memutils.h"
 

src/backend/access/spgist/spgutils.c

@@ -22,6 +22,7 @@
 #include "storage/bufmgr.h"
 #include "storage/indexfsm.h"
 #include "storage/lmgr.h"
+#include "utils/builtins.h"
 #include "utils/index_selfuncs.h"
 #include "utils/lsyscache.h"
 

src/backend/access/transam/xlogfuncs.c

@@ -18,7 +18,6 @@
 
 #include "access/htup_details.h"
 #include "access/xlog.h"
-#include "access/xlog_fn.h"
 #include "access/xlog_internal.h"
 #include "access/xlogutils.h"
 #include "catalog/catalog.h"