diff --git a/include/osg/GLExtensions b/include/osg/GLExtensions
index e1c558e9f..bf6d58cf3 100644
--- a/include/osg/GLExtensions
+++ b/include/osg/GLExtensions
@@ -15,6 +15,8 @@
 #define OSG_GLEXTENSIONS 1
 
 #include <osg/Export>
+#include <stdlib.h>
+#include <string.h>
 #include <string>