[Qt-jambi-interest] Tracking down a problem in native-code

[Gunnar Sletta]

Tom Schindl wrote:
> Hi Gunnar,
> 
> The first thing I found out is that it looks like a problem in QList and
> Event-Listeners.
> 
>> Thread 0 Crashed:
>> 0   <<00000000>> 	0x26594a85 0 + 643385989
>> 1   libqtjambi.jnilib 	0x0275367e qtjambi_event_notify(void**) + 80
>> 2   libQtCore.4.dylib 	0x0896fd53 QInternal::activateCallbacks(QInternal::Callback, void**) + 115
>> 3   libQtCore.4.dylib 	0x08a60b11 QCoreApplication::notifyInternal(QObject*, QEvent*) + 49
>> 4   libQtCore.4.dylib 	0x08a63de1 QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) + 689
>> 5   libQtGui.4.dylib  	0x08d4d68b QEventDispatcherMac::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) + 107
>> 6   libQtCore.4.dylib 	0x08a60231 QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) + 65
>> 7   libQtCore.4.dylib 	0x08a602fd QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) + 157
>> 8   libQtCore.4.dylib 	0x08a64021 QCoreApplication::exec() + 161

I'm afraid not ;)

This only states that the problem occured while an event was being 
delivered, most likely it was a DeleteLater event, caused by a GUI 
object being collected on the GC thread and the deletion being delegated 
back to the GUI thread. We spent a lot of effort ironing out these 
issues back in may, and I was rather confident that we had caught these 
problems, but alas..

Places to look:
  * Do you have any disposeLater() or dispose() in your code?
  * Start looking at the parts of the app where you use temporary GUI 
objects: QFonts, QPixmaps, QRegions, QGraphicsItems, QBrushes, QPens, etc.

best regards,
Gunnar