diff --git a/simgear/scene/model/SGClipGroup.cxx b/simgear/scene/model/SGClipGroup.cxx
index fdf9305a..bbddbcb0 100644
--- a/simgear/scene/model/SGClipGroup.cxx
+++ b/simgear/scene/model/SGClipGroup.cxx
@@ -19,6 +19,10 @@
  *
  */
 
+#ifdef HAVE_CONFIG_H
+#  include <simgear_config.h>
+#endif
+
 #include "SGClipGroup.hxx"
 
 #include <osg/ClipPlane>