[Interest] Blind binding crash on Qml instantiation

[Nuno Santos]

Hi,

I’m having a blind qml crash. I have been commenting the code on/off all day long and I can’t seem to find a pattern, something I know exactly what it is. What is the procedure to find such problems? 

When I manage to catch a crash with the debugger this is what I can find:

Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0   org.qt-project.QtQml          	0x000000010ca9a0a4 QQmlBinding::write(QQmlPropertyData const&, QV4::Value const&, bool, QFlags<QQmlPropertyPrivate::WriteFlag>) + 596
1   org.qt-project.QtQml          	0x000000010ca99bf8 QQmlBinding::update(QFlags<QQmlPropertyPrivate::WriteFlag>) + 952
2   org.qt-project.QtQml          	0x000000010caa9b30 QQmlObjectCreator::finalize(QQmlInstantiationInterrupt&) + 272
3   org.qt-project.QtQml          	0x000000010ca34fa0 QQmlIncubatorPrivate::incubate(QQmlInstantiationInterrupt&) + 1376
4   org.qt-project.QtQml          	0x000000010ca35d31 QQmlIncubationController::incubateFor(int) + 129
5   org.qt-project.QtQuick        	0x000000010bed2f05 QQuickWindowIncubationController::incubate() + 69
6   org.qt-project.QtCore         	0x000000010d066670 QObject::event(QEvent*) + 48
7   org.qt-project.QtCore         	0x000000010d03a80f QCoreApplicationPrivate::notify_helper(QObject*, QEvent*) + 303
8   org.qt-project.QtCore         	0x000000010d03a46d QCoreApplication::notify(QObject*, QEvent*) + 45
9   org.qt-project.QtCore         	0x000000010d03a3f4 QCoreApplication::notifyInternal2(QObject*, QEvent*) + 164
10  org.qt-project.QtCore         	0x000000010d091662 QTimerInfoList::activateTimers() + 1266
11  libqcocoa.dylib               	0x000000010f933772 QCocoaEventDispatcherPrivate::activateTimersSourceCallback(void*) + 18
12  com.apple.CoreFoundation      	0x00007fff981d6881 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
13  com.apple.CoreFoundation      	0x00007fff981b5fbc __CFRunLoopDoSources0 + 556
14  com.apple.CoreFoundation      	0x00007fff981b54df __CFRunLoopRun + 927
15  com.apple.CoreFoundation      	0x00007fff981b4ed8 CFRunLoopRunSpecific + 296
16  com.apple.HIToolbox           	0x00007fff8a7af935 RunCurrentEventLoopInMode + 235
17  com.apple.HIToolbox           	0x00007fff8a7af76f ReceiveNextEventCommon + 432
18  com.apple.HIToolbox           	0x00007fff8a7af5af _BlockUntilNextEventMatchingListInModeWithFilter + 71
19  com.apple.AppKit              	0x00007fff970f3df6 _DPSNextEvent + 1067
20  com.apple.AppKit              	0x00007fff970f3226 -[NSApplication _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 454
21  com.apple.AppKit              	0x00007fff970e7d80 -[NSApplication run] + 682
22  libqcocoa.dylib               	0x000000010f93437f QCocoaEventDispatcher::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) + 2191
23  org.qt-project.QtCore         	0x000000010d0367a1 QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) + 401
24  org.qt-project.QtCore         	0x000000010d03aa65 QCoreApplication::exec() + 341
25  com.imaginando.LK             	0x000000010b416317 main + 1879 (main.cpp:249)
26  com.imaginando.LK             	0x000000010b3bccb4 start + 52

Regards,

Nuno