Qt's GMainLoop integration should use g_main_context_push_thread_default to push the GMainContext that is created for a newly created QThread to GLib. This way applications and libraries that use threads (like DBus libraries) can access the GMainContext by asking for g_main_context_get_thread_default (for example to execute asynchronous methods' callbacks on).

The TLS free function in GLib would clean up the registration, but it's more correct to use g_main_context_pop_thread_default when the context is disposed.

I have attached a patch that adds the push and popping of the GMainContext to Qt's QEventDispatcher.