+++ This bug was initially created as a clone of Bug #564944 +++

Constructors which throw errors generate code (in the *_construct function) code that looks something like this:

Foo* foo_construct (GType object_type, GError** error) {
	GError * inner_error;
	Foo * self;
	inner_error = NULL;
	self = g_object_newv (object_type, 0, NULL);
	inner_error = g_error_new (ERROR, ERROR_FOOBAR, "Foobar!");
	if (inner_error != NULL) {
		g_propagate_error (error, inner_error);
		return;
	}
	return self;
}

Notice that inside of the if block, there is a return without a value, which can cause problems later on (warnings about assertion `G_IS_OBJECT (object)' failed, segfaults). I think that if there is an error, it should either unref the object and return null, or return self and leave it to the caller to unref (which it does).