[Mac/Cocoa 64-bits] QColorDialog random crashes

64x Cocoa built: QColorDialog random crashes while shown as a modal dialog:

Thread 0 Crashed:
0 libSystem.B.dylib 0x00007fff80680cbb tiny_malloc_from_free_list + 69
1 libSystem.B.dylib 0x00007fff80679bcf szone_malloc + 203
2 libSystem.B.dylib 0x00007fff80679acf malloc_zone_malloc + 82
3 libSystem.B.dylib 0x00007fff80679a60 malloc + 44
4 com.apple.CoreFoundation 0x00007fff842420a6 _CFDoExceptionOperation + 550
5 com.apple.AppKit 0x00007fff82888e26 _NSAppKitLock + 81
6 com.apple.AppKit 0x00007fff828c51de -[NSApplication(NSWindowCache) _updateWindowsUsingCache] + 68
7 com.apple.AppKit 0x00007fff828c512b -[NSApplication updateWindows] + 87
8 com.apple.AppKit 0x00007fff828c506a _handleWindowsNeedUpdateNote + 66
9 com.apple.CoreFoundation 0x00007fff841cb3ea __CFRunLoopDoObservers + 506
10 com.apple.CoreFoundation 0x00007fff841cc6b4 CFRunLoopRunSpecific + 836
11 com.apple.HIToolbox 0x00007fff84c00d0e RunCurrentEventLoopInMode + 278
12 com.apple.HIToolbox 0x00007fff84c00aa3 ReceiveNextEventCommon + 161
13 com.apple.HIToolbox 0x00007fff84c009ef BlockUntilNextEventMatchingListInMode + 79
14 com.apple.AppKit 0x00007fff828c3e70 _DPSNextEvent + 603
15 com.apple.AppKit 0x00007fff828c37b1 -[NSApplication nextEventMatchingMask:untilDate:inMode:dequeue:] + 136
16 com.apple.AppKit 0x00007fff82b03de5 -[NSApplication _realDoModalLoop:peek:] + 290
17 com.apple.AppKit 0x00007fff82bf8d5a -[NSApplication runModalSession:] + 58
18 QtGui 0x0000000122955c8c QEventDispatcherMac::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) + 1420
19 QtCore 0x00000001237b8e44 QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) + 68
20 QtCore 0x00000001237b9154 QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) + 180
21 QtGui 0x0000000122df4295 QDialog::exec() + 229
22 QtGui 0x0000000122df2ac2 QColorDialog::getColor(QColor const&, QWidget*, QString const&, QFlags<QColorDialog::ColorDialogOption>) + 114

It looks like exception thrown from Objective-c method not properly handled .