Loading...

XML

Word

Printable

Details

Type: Bug
Resolution: Duplicate
Priority: P1: Critical
Fix Version/s: None
Affects Version/s: 6.2.1
Component/s: GUI: Painting
Labels:
None
Environment:
Windows 10, MSVC 2019

Platform/s:

All

Description

Sporadic crash on QPMCache::flushDetachedPixmaps call.


Exception thrown: read access violation.
**QPMCache::get**(...) returned nullptr.

 	Qt6Guid.dll!qHash(const QPixmapCache::Key & k, unsigned __int64 seed) Line 258	C++
 	Qt6Guid.dll!QHashPrivate::calculateHash<QPixmapCache::Key>(const QPixmapCache::Key & t, unsigned __int64 seed) Line 103	C++
 	Qt6Guid.dll!QHashPrivate::Data<QCache<QPixmapCache::Key,QPixmapCacheEntry>::Node>::find(const QPixmapCache::Key & key) Line 592	C++
 	Qt6Guid.dll!QCache<QPixmapCache::Key,QPixmapCacheEntry>::unlink(QCache<QPixmapCache::Key,QPixmapCacheEntry>::Node * n) Line 159	C++
 	Qt6Guid.dll!QCache<QPixmapCache::Key,QPixmapCacheEntry>::trim(__int64 m) Line 187	C++
 	Qt6Guid.dll!QCache<QPixmapCache::Key,QPixmapCacheEntry>::setMaxCost(__int64 m) Line 211	C++
>	Qt6Guid.dll!QPMCache::flushDetachedPixmaps(bool nt) Line 291	C++
 	Qt6Guid.dll!QPMCache::timerEvent(QTimerEvent * __formal) Line 312	C++
 	Qt6Cored.dll!QObject::event(QEvent * e) Line 1343	C++
 	Qt6Widgetsd.dll!QApplicationPrivate::notify_helper(QObject * receiver, QEvent * e) Line 3405	C++
 	Qt6Widgetsd.dll!QApplication::notify(QObject * receiver, QEvent * e) Line 2764	C++
 	Qt6Cored.dll!QCoreApplication::notifyInternal2(QObject * receiver, QEvent * event) Line 1063	C++
 	Qt6Cored.dll!QCoreApplication::sendEvent(QObject * receiver, QEvent * event) Line 1472	C++
 	Qt6Cored.dll!QEventDispatcherWin32Private::sendTimerEvent(int timerId) Line 407	C++
 	Qt6Cored.dll!qt_internal_proc(HWND__ * hwnd, unsigned int message, unsigned __int64 wp, __int64 lp) Line 231	C++
 	[External Code]	
 	Qt6Cored.dll!QEventDispatcherWin32::processEvents(QFlags<enum QEventLoop::ProcessEventsFlag> flags) Line 543	C++
 	Qt6Guid.dll!QWindowsGuiEventDispatcher::processEvents(QFlags<enum QEventLoop::ProcessEventsFlag> flags) Line 72	C++
 	Qt6Cored.dll!QEventLoop::processEvents(QFlags<enum QEventLoop::ProcessEventsFlag> flags) Line 140	C++
 	Qt6Cored.dll!QEventLoop::exec(QFlags<enum QEventLoop::ProcessEventsFlag> flags) Line 230	C++
 	Qt6Cored.dll!QCoreApplication::exec() Line 1378	C++
 	Qt6Guid.dll!QGuiApplication::exec() Line 1861	C++
 	Qt6Widgetsd.dll!QApplication::exec() Line 2615	C++

It crashes when trying to calculate qHash() for null value (QPixmapCache::Key).

Take a look on debugger screenshot below.

Unfortunately I have now exact steps or examples,

but it seems that adding trivial check on null value in qHash(QPixmapCache::Key) may fix the issue.

I got this crash on Windows 10. But probably it's relevant for all platforms.