diff --git a/glib/gtester.c b/glib/gtester.c
index 89f9294c0..4edcf2d29 100644
--- a/glib/gtester.c
+++ b/glib/gtester.c
@@ -17,6 +17,8 @@
  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  * Boston, MA 02111-1307, USA.
  */
+#include "config.h"
+
 #include <glib.h>
 #include <gstdio.h>
 #include <string.h>