The small vala application generated warnings with gcc, because it has a unused variable (boxed)

----
public class Foo : GLib.Object {
  bool _bar;
  public bool bar {
    get {return _bar;}
  }
}

void main () {
  var a = new Foo ();
}

----
static void foo_get_property (GObject * object, guint property_id, GValue * value, GParamSpec * pspec) {
	Foo * self;
	gpointer boxed;
	self = FOO (object);
	switch (property_id) {
		case FOO_BAR:
		g_value_set_boolean (value, foo_get_bar (self));
		break;
		default:
		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
		break;
	}
}