diff --git a/jsonpull/jsonpull.cpp b/jsonpull/jsonpull.cpp
index 8b23ba75..6ddbb943 100644
--- a/jsonpull/jsonpull.cpp
+++ b/jsonpull/jsonpull.cpp
@@ -1,4 +1,6 @@
+#ifndef _GNU_SOURCE
 #define _GNU_SOURCE  // for asprintf()
+#endif
 #include <stdio.h>
 #include <stdlib.h>
 #include <ctype.h>