diff --git a/src/gui.h b/src/gui.h
index aecba27..7bcbfa3 100644
--- a/src/gui.h
+++ b/src/gui.h
@@ -22,7 +22,10 @@
 #  include "gui_gtk_vms.h"
 # endif // VMS
 # include <X11/Intrinsic.h>
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Wstrict-prototypes"
 # include <gtk/gtk.h>
+# pragma GCC diagnostic pop
 #endif
 
 #ifdef FEAT_GUI_HAIKU