diff --git a/simgear/screen/shader.cpp b/simgear/screen/shader.cpp
index 98284f93..16f89b59 100644
--- a/simgear/screen/shader.cpp
+++ b/simgear/screen/shader.cpp
@@ -18,6 +18,9 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
+#ifdef HAVE_CONFIG_H
+#  include <simgear_config.h>
+#endif 
 
 #include <simgear/debug/logstream.hxx>
 #include "shader.h"