Reserve space for a pointer in GtkDrawingArea

It was pointed out that this will let us add a private pointer
without abi break in the future, should we ever need one.

diff --git a/gtk/gtkdrawingarea.h b/gtk/gtkdrawingarea.h
index 553b9be97d432d5d1a72e52ddb6d04e1d9e885a6..c40bc934a16cccc6664365a05399d5d64cf5c49b 100644 (file)
--- a/gtk/gtkdrawingarea.h
+++ b/gtk/gtkdrawingarea.h
@@ -51,6 +51,9 @@ typedef struct _GtkDrawingAreaClass  GtkDrawingAreaClass;
 struct _GtkDrawingArea
 {
   GtkWidget widget;
+
+  /*< private >*/
+  gpointer dummy;
 };
 
 struct _GtkDrawingAreaClass