--- ext/posix/posix.c	2009-08-06 13:11:15.000000000 +0200
+++ ext/posix/posix.c.oden	2009-09-25 19:12:30.000000000 +0200
@@ -18,6 +18,10 @@
 
 /* $Id: posix.c 286880 2009-08-06 11:11:15Z jani $ */
 
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE 1
+#endif
+
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif