QQmlDelegateModel::_q_itemsChanged crash

void QQmlDelegateModel::_q_itemsChanged(int index, int count, 
                                        const QVector<int> &roles)
{
    Q_D(QQmlDelegateModel);
    if (count <= 0 || !d->m_complete)
        return;

    if (d->m_adaptorModel.notify(d->m_cache, index, count, roles)) --|
                                                                     |
                                                                     |
                                                                     |
bool VDMModelDelegateDataType::notify(     <-------------------------|        
   const QQmlAdaptorModel &,
   /*-------------------------------------------
    * "d->m_cache by refercence"
    *------------------------------------------*/
   const QList<QQmlDelegateModelItem *> &items,
   int index,
   int count,
   const QVector<int> &roles) const
{

   //.....
   
    /*-------------------------------------------
     * "c - calculated once at the start"
     *------------------------------------------*/
    for (int i = 0, c = items.count();  i < c; ++i) {  
        /*--------------------------------------------------------
         * "i - maybe invalid if items.count() changed"
         * " (items is reference to d->m_cache)"
         *------------------------------------------------------*/
        QQmlDelegateModelItem *item = items.at(i);  ------------- -----|
        const int idx = item->modelIndex();                            |
        if (idx >= index && idx < index + count) {                     |
            for (int i = 0; i < signalIndexes.count(); ++i)            |
           /*-----------------------------------------------------     |
           * "Maybe modify d->m_cache.count()"                         |
           * "e.g. collapse/expand item(geometry changed), scroll"     |
           *----------------------------------------------------*/     |
              QMetaObject::activate(item, signalIndexes.at(i), 0);  <--|
                                                                     
        }
    }
}

/*----------------------------------------------------------------------------
 * "d->m_cache changed:"
 * "Crash  on the next iteration of the loop: VDMModelDelegateDataType::notify"
 *---------------------------------------------------------------------------*/
1   QQmlDelegateModelPrivate::removeCacheItem                 
2   QQmlDelegateModelItem::Dispose                             
3   QQmlDelegateModelPrivate::release                         
4   QQmlDelegateModel::release                                 
5   QQuickItemViewPrivate::releaseItem                         
/*----------------------------------------------------------------------------
 * "CacheBuffer changed"
 *---------------------------------------------------------------------------*/
8   QQuickListViewPrivate::removeNonVisibleItems             
9   QQuickItemViewPrivate::refill                        
10  QQuickItemViewPrivate::refill                         
11  QQuickItemViewPrivate::refillOrLayout                   
12  QQuickListView::viewportMoved                           
13  QQuickFlickablePrivate::itemGeometryChanged     
14  QQuickItemViewPrivate::itemGeometryChanged  
15  QQuickListViewPrivate::itemGeometryChanged  
16  QQuickItem::geometryChanged               
17  QQuickItem::setY                                
18  QQuickFlickablePrivate::setViewportY              
19  QQuickTimeLineValueProxy<QQuickFlickablePrivate>::setValue 
20  QQuickFlickable::setContentY                        
21  QQuickListViewPrivate::setPosition                  
26  QQuickItem::setHeight                             
30  QQmlPropertyPrivate::write                        
31  QQmlPropertyPrivate::writeValueProperty         
33  QQmlPropertyPrivate::write                      
34  QSmoothedAnimation::updateCurrentTime           
35  QAbstractAnimationJob::setCurrentTime           
36  QAbstractAnimationJob::setState                 
37  QAbstractAnimationJob::start                    
38  QSmoothedAnimation::restart                     
39  QQuickListViewPrivate::updateHighlight          
40  QQuickItemViewPrivate::itemGeometryChanged      
41  QQuickListViewPrivate::itemGeometryChanged      
42  QQuickItem::geometryChanged                     
/*----------------------------------------------------------------------------
 *  "Item geometry changed"
 *---------------------------------------------------------------------------*/
43  QQuickItem::setHeight               
48  QQmlVMEMetaObject::metaCall         
49  QMetaObject::metacall                     
50  QQmlBinding::write                       
51  QQmlBinding::update                      
52  QQmlBinding::expressionChanged           
70  QMetaObject::activate                    
/*----------------------------------------------------------------------------
 *  "Update cache items (d->m_cahce)"
 *---------------------------------------------------------------------------*/
72  VDMModelDelegateDataType::notify    
73  QQmlAdaptorModel::notify            
74  QQmlDelegateModel::_q_itemsChanged  
75  QQmlDelegateModel::_q_dataChanged   
/*---------------------------------------------------------------------------
 * "Model dataChanged : Expand item"
 *---------------------------------------------------------------------------*/
81  QAbstractItemModel::dataChanged