$OpenBSD$
--- cmake/Config.h.in.orig	Sun May 31 08:26:00 2009
+++ cmake/Config.h.in	Thu Jun 26 13:16:36 2014
@@ -30,6 +30,7 @@
 #define _GG_Config_h_
 
 
+#define GG_USE_SYSTEM_LTDL @int_have_system_ltdl@
 #define GG_USE_DEVIL_IMAGE_LOAD_LIBRARY @int_have_devil@
 #define GG_HAVE_LIBJPEG @int_have_jpeg@
 #define GG_HAVE_LIBPNG @int_have_png@