So I'm running into some GDM code that connects to the selection-changed signal of a file chooser button, and under certain circumstances runs code like:

g_signal_handlers_disconnect_by_func (file_chooser,                                       handler, file_chooser);
						      
gtk_file_chooser_set_filename (GTK_FILE_CHOOSER (file_chooser),                             filename);

g_signal_connect (G_OBJECT (file_chooser), "selection-changed", 
    	          G_CALLBACK (handler), file_chooser);

This is causing recursion.  Presumably the disconnect_by_func is there to prevent the recursion.  This must have broke when merging the async branch.

The file chooser chould choose to not emit a selection-changed signal if the app calls set_filename with a filename that's already selected.  That would keep code like this working.