diff --git a/legacy/eio/src/lib/eio_private.h b/legacy/eio/src/lib/eio_private.h
index 9b29f4a26d..67578bf315 100644
--- a/legacy/eio/src/lib/eio_private.h
+++ b/legacy/eio/src/lib/eio_private.h
@@ -5,10 +5,6 @@
 # include "config.h"
 #endif
 
-#ifndef _GNU_SOURCE
-# define _GNU_SOURCE
-#endif
-
 #ifdef HAVE_FEATURES_H
 # include <features.h>
 #endif