diff --git a/gst-libs/gst/gl/gstglcontext.c b/gst-libs/gst/gl/gstglcontext.c
index 34b14b82f1..5e2d87cba0 100644
--- a/gst-libs/gst/gl/gstglcontext.c
+++ b/gst-libs/gst/gl/gstglcontext.c
@@ -40,6 +40,10 @@
 #define _GNU_SOURCE
 #endif
 
+#ifndef GL_NUM_EXTENSIONS
+#define GL_NUM_EXTENSIONS 0x0000821d
+#endif
+
 #include <gmodule.h>
 
 #include "gl.h"