void QGraphicsScenePrivate::_q_processDirtyItems()
{
    processDirtyItemsEmitted = false;

    if (updateAll) {
        Q_ASSERT(calledEmitUpdated);  // <<< *** ASSERTION FAILURE ***
        // No need for further processing (except resetting the dirty states).
        // The growingItemsBoundingRect is updated in _q_emitUpdated.
        for (int i = 0; i < topLevelItems.size(); ++i)
            resetDirtyItem(topLevelItems.at(i), /*recursive=*/true);
        return;
    }

    const bool wasPendingSceneUpdate = calledEmitUpdated;
    const QRectF oldGrowingItemsBoundingRect = growingItemsBoundingRect;

    // Process items recursively.
    for (int i = 0; i < topLevelItems.size(); ++i)
        processDirtyItemsRecursive(topLevelItems.at(i));

    dirtyGrowingItemsBoundingRect = false;
    if (!hasSceneRect && oldGrowingItemsBoundingRect != growingItemsBoundingRect)
        emit q_func()->sceneRectChanged(growingItemsBoundingRect);

    if (wasPendingSceneUpdate)
        return;

    for (int i = 0; i < views.size(); ++i)
        views.at(i)->d_func()->processPendingUpdates();

    if (calledEmitUpdated) {
        // We did a compatibility QGraphicsScene::update in processDirtyItemsRecursive
        // and we cannot wait for the control to reach the eventloop before the
        // changed signal is emitted, so we emit it now.
        _q_emitUpdated();
    }

    // Immediately dispatch all pending update requests on the views.
    for (int i = 0; i < views.size(); ++i)
        views.at(i)->d_func()->dispatchPendingUpdateRequests();
}