Create a list of a million QTimer objects using reserve(int).

buildObjectListWithReserve()

QList<QObject*> buildObjectListWithReserve()
{
    qint64 size = 10000000;
    QList<QObject*> objectList;
    objectList.reserve(size);
    for (int i = 0; i < size; i++)
    {
        objectList << new QTimer();
    }
    return objectList;
}