diff --git a/gtk/gtkcheckmenuitem.h b/gtk/gtkcheckmenuitem.h
index 317639b281..c0d6b175ad 100644
--- a/gtk/gtkcheckmenuitem.h
+++ b/gtk/gtkcheckmenuitem.h
@@ -70,11 +70,7 @@ struct _GtkCheckMenuItemClass
 
   /*< private >*/
 
-  /* Padding for future expansion */
-  void (*_gtk_reserved1) (void);
-  void (*_gtk_reserved2) (void);
-  void (*_gtk_reserved3) (void);
-  void (*_gtk_reserved4) (void);
+  gpointer padding[8];
 };