Crash in QQuickItemView through recursive item release

QQuickItemViewPrivate::releaseItem() is called with during clear(), setCurrentIndex(), updatePolish(), setModel() and others. In releaseItem the current item is finally deleted but before it's quick item is possibly reparented:

item->item->setParentItem(nullptr);

This reparenting action itself may trigger further signals and these signals could again cause QQuickItemViewPrivate::releaseItem() to be called recursively.

This causes a crash because the currentItem pointer is nulled after releaseItem() is called:

releaseItem(currentItem, QQmlDelegateModel::NotReusable);
currentItem = nullptr;

Here is the scenario:

releaseItem() is called with currentItem: 

bool QQuickItemViewPrivate::releaseItem(FxViewItem *item, QQmlInstanceModel::ReusableFlag reusableFlag)
{
    ......
            item->item->setParentItem(nullptr);
    ......
    delete item;
    return ...;
}

Here, setParentItem causes recursive call releaseItem() with currentItem which is finally deleted. After returning from setParentItem the pointer item is dangling. Thus, its final deletion causes a crash.

I suggest nulling currentItem pointer before calling releaseItem():

auto oldCurrentItem = currentItem;
currentItem = nullptr; 
releaseItem(oldCurrentItem, QQmlDelegateModel::NotReusable);