Do not try to call gtk_object_get_data on non-gtk objects, it's not all that good an idea. :-)

Rev: src/post_modules/GTK/source/support.c:1.13

src/post_modules/GTK/source/support.c

@@ -307,6 +307,16 @@ GdkImage *gdkimage_from_pikeimage( struct object *img, int fast, GdkImage *i )
   return i;
 }
 
+#define IS_OBJECT_PROGRAM(X)                 \
+!( ((X) == pgtk_style_program)               \
+|| ((X) == pgtk_CTreeNode_program)           \
+|| ((X) == pgtk_CTreeRow_program)            \
+|| ((X) == pgtk_icon_list_item_program)      \
+|| ((X) == pgtk_plot_dataset_program)        \
+|| ((X) == pgtk_psfont_program)              \
+|| ((X) == pgtk_selection_data_program)      \
+|| ((X) == pgtk_sheet_child_program))
+
 void push_gtkobjectclass(void *obj, struct program *def)
 {
   struct object *o;
@@ -315,7 +325,8 @@ void push_gtkobjectclass(void *obj, struct program *def)
     push_int(0);
     return;
   }
-  if( (o=gtk_object_get_data(GTK_OBJECT(obj), "pike_object")) )
+  if( IS_OBJECT_PROGRAM(def) )
+    if( (o=gtk_object_get_data(((void *)obj), "pike_object")) )
     {
       ref_push_object( o );
       return;