diff --git a/bench/bench-qlibc.c b/bench/bench-qlibc.c
index ff79c3ba..39721af7 100644
--- a/bench/bench-qlibc.c
+++ b/bench/bench-qlibc.c
@@ -1,4 +1,5 @@
 #define NDEBUG
+#define _GNU_SOURCE 
 
 #include <stdlib.h>
 #include <stdio.h>