the #GClosure to which the marshaller belongs
a #GValue to store the return value. May be %NULL if the callback of @closure doesn't return a value.
the instance on which the closure is invoked.
va_list of arguments to be passed to the closure.
additional data specified when registering the marshaller, see g_closure_set_marshal() and g_closure_set_meta_marshal()
the #GType of each argument from @args.
The #GVaClosureMarshal equivalent to g_cclosure_marshal_VOID__VARIANT().