gtk_tree_view_insert_columns* seem to ignore fixed-mode

[Stefan Kost <ensonic hora-obscura de>]

hi hi,

I have a treeview that is using fixed height mode. I add my columns using
  index=gtk_tree_view_insert_columns_with_attributes(...);
Then I get the tree_column object via
  tree_column=gtk_tree_view_get_column(...);
and use g_object_set(tree_column,"sizing",GTK_TREE_VIEW_COLUMN_FIXED,NULL);
But that is already too late.
The docs for gtk_tree_view_insert_columns_with_attributes() tell that one has to 
set the sizing property, but the attributes I pass to this methods are not 
attributes for the treeview column.
A bug? or how to do this properly. Shouldn't 
gtk_tree_view_insert_columns_with_attributes() check the result of 
gtk_tree_view_get_fixed_mode() and create appropriate columns?

Stefan