QQmlMetaType::registerInternalCompositeType() leaks

CompositeMetaTypeIds QQmlMetaType::registerInternalCompositeType(const QByteArray &className)
{
    QByteArray ptr = className + '*';
    QByteArray lst = "QQmlListProperty<" + className + '>';

    QMetaType ptr_type(new QQmlMetaTypeInterface<QObject*>(ptr));
    QMetaType lst_type(new QQmlMetaTypeInterface<QQmlListProperty<QObject>>(lst));

    QQmlMetaTypeDataPtr data;
    data->qmlLists.insert(lst_type.id(), ptr_type.id());

    return {ptr_type, lst_type};
}