Commit 
da9b580 mistakenly put a system header before postgres.h (which
includes c.h).  That can cause portability issues and broke (at least)
builds with older Windows compilers.
Discovered by Mark Dilger.
Discussion: https://postgr.es/m/
BF04A27A-D132-4927-A80A-
BAD18695E954@gmail.com
  *
  *-------------------------------------------------------------------------
  */
-#include <sys/stat.h>
-
 #include "postgres.h"
 
+#include <sys/stat.h>
+
 #include "common/file_perm.h"
 #include "libpq/libpq-be.h"
 #include "libpq/pqcomm.h"