Created attachment 274591 [details]
test.c

I've just installed current Fedora rawhide, which includes

   gnome-shell-3.12.1-1.fc21.x86_64
   gtk3-3.12.1-1.fc21.x86_64
   glib2-2.40.0-1.fc21.x86_64

and when an application calls gtk_application_inhibit() the process spawns couple critical warnings on console:

> (test:3966): GLib-CRITICAL **: g_variant_get_type: assertion 'value != NULL'
> failed
>
> (test:3966): GLib-CRITICAL **: g_variant_type_is_subtype_of: assertion
> 'g_variant_type_check (type)' failed
>
> (test:3966): GLib-CRITICAL **: g_variant_get_type_string: assertion 'value
> != NULL' failed
> 
> (test:3966): GLib-ERROR **: g_variant_new: expected GVariant of type 'u'
> but received value has type '(null)'

which finally ends with a

> Program received signal SIGTRAP, Trace/breakpoint trap.

and below backtrace. The attached is a reproducer, compile params are at the first line of it.

+ Trace 233481