diff --git a/src/libstrongswan/fetcher/fetcher_manager.c b/src/libstrongswan/fetcher/fetcher_manager.c
index 286679616..3a9e6322d 100644
--- a/src/libstrongswan/fetcher/fetcher_manager.c
+++ b/src/libstrongswan/fetcher/fetcher_manager.c
@@ -15,6 +15,8 @@
  * $Id$
  */
 
+#define _GNU_SOURCE
+
 #include "fetcher_manager.h"
 
 #include <debug.h>