/* Copyright 1996, 2000 Free Software Foundation */
-#ifdef HAVE_UNISTD_H
+#define _GNU_SOURCE
+#include "src/internal_config.h"
+#if HAVE_UNISTD_H
#include <unistd.h> /* Prototypes for lseek, sbrk (maybe) */
#endif
+
#include "mfree.c"
#include "mmalloc.c"
#include "mrealloc.c"
#include "mmorecore.c"
#include "mm_legacy.c"
#include "mm_module.c"
-#include "mm_diff.c"