Missing support for g_autoptr
Since some years, the macro to be used to derive GObject classes is G_DECLARE_DERIVABLE_TYPE.
Right now it can't be used with AtkObject because it would fail due a lack of glib_autoptr_clear_AtkObject.
As far as I understand we would only need to use the macro G_DEFINE_AUTOPTR_CLEANUP_FUNC on AtkObject.h. But I would need to confirm.
See gtk commit 8c361fd7e271f5b4adae2d99e58d515cf10bb861 as reference, and all the *autocleanups.h files on gtk and other gnome projects.