Swap order of extern/static and pg_nodiscard

When pg_nodiscard was first added, the C standard draft had it as a
function specifier, and so the code comment about placement was
written with that in mind.  The final C23 standard has it as an
attribute and the placement rules are a bit different for that.
Specifically, it needs to be before extern or static.  (Or at least
both current clang and gcc require that.)  So just swap these.  (To be
clear: The current implementation with gcc attributes doesn't care.
This change is just for maximum forward compatibility for non-gcc
compilers.)  This also keeps the order consistent with the previously
introduced pg_noreturn.  Also update the code comment to reflect the
mentioned developments since its introduction.

Reviewed-by: Dagfinn Ilmari Mannsåker <[email protected]>
Reviewed-by: Andres Freund <[email protected]>
Discussion: https://www.postgresql.org/message-id/flat/pxr5b3z7jmkpenssra5zroxi7qzzp6eswuggokw64axmdixpnk@zbwxuq7gbbcw

1 files changed, 1 insertions, 1 deletions

diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index 1233e07d7da..24444cbc365 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -444,7 +444,7 @@ extern ArrayType *GUCArrayDelete(ArrayType *array, const char *name);
 extern ArrayType *GUCArrayReset(ArrayType *array);
 
 extern void *guc_malloc(int elevel, size_t size);
-extern pg_nodiscard void *guc_realloc(int elevel, void *old, size_t size);
+pg_nodiscard extern void *guc_realloc(int elevel, void *old, size_t size);
 extern char *guc_strdup(int elevel, const char *src);
 extern void guc_free(void *ptr);