diff --git a/src/gui_gtk_x11.c b/src/gui_gtk_x11.c
index fd582dd..d0d946c 100644
--- a/src/gui_gtk_x11.c
+++ b/src/gui_gtk_x11.c
@@ -1246,6 +1246,7 @@
 	}
     }
 
+#ifdef GDK_KEY_dead_circumflex
     // Belgian Ctrl+[ workaround
     if (len == 0 && key_sym == GDK_KEY_dead_circumflex)
     {
@@ -1259,6 +1260,7 @@
 	// are confusing code downstream
 	return TRUE;
     }
+#endif
 
     if (len == 0)   // Unrecognized key
 	return TRUE;