crash on "step into" on OS X

* thread #1: tid = 0x3053a, 0x000000010a8281b6 libDebugger.dylib`Debugger::Internal::WatchModel::data(QModelIndex const&, int) const + 54, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=EXC_I386_GPFLT)
  * frame #0: 0x000000010a8281b6 libDebugger.dylib`Debugger::Internal::WatchModel::data(QModelIndex const&, int) const + 54
    frame #1: 0x00000001001125b3 libUtils.1.0.0.dylib`Utils::Internal::BaseTreeViewPrivate::suggestedColumnSize(int) const + 387
    frame #2: 0x0000000100111dc2 libUtils.1.0.0.dylib`Utils::Internal::BaseTreeViewPrivate::resizeColumns() + 178
    frame #3: 0x0000000101043b82 QtCore`QMetaObject::activate(QObject*, int, int, void**) + 2994
    frame #4: 0x000000010a82a87b libDebugger.dylib`Debugger::Internal::WatchHandler::notifyUpdateStarted() + 43
    frame #5: 0x000000010a9137bb libDebugger.dylib`Debugger::Internal::LldbEngine::doUpdateLocals(Debugger::Internal::UpdateParameters const&) + 203
    frame #6: 0x000000010a79393b libDebugger.dylib`Debugger::Internal::DebuggerEngine::updateLocals() + 59
    frame #7: 0x000000010a90f822 libDebugger.dylib`Debugger::Internal::LldbEngine::handleContinuation(Debugger::Internal::GdbMi const&) + 306
    frame #8: 0x000000010a90860f libDebugger.dylib`Debugger::Internal::LldbEngine::handleResponse(QByteArray const&) + 1247
    frame #9: 0x000000010103c753 QtCore`QObject::event(QEvent*) + 755
    frame #10: 0x00000001002966fb QtWidgets`QApplicationPrivate::notify_helper(QObject*, QEvent*) + 251
    frame #11: 0x0000000100299ade QtWidgets`QApplication::notify(QObject*, QEvent*) + 8318
    frame #12: 0x0000000101013e8b QtCore`QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) + 971
    frame #13: 0x000000010458608e libqcocoa.dylib`___lldb_unnamed_function445$$libqcocoa.dylib + 190
    frame #14: 0x0000000104586911 libqcocoa.dylib`___lldb_unnamed_function457$$libqcocoa.dylib + 33
    frame #15: 0x00007fff8a946a01 CoreFoundation`__CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
    frame #16: 0x00007fff8a938b8d CoreFoundation`__CFRunLoopDoSources0 + 269
    frame #17: 0x00007fff8a9381bf CoreFoundation`__CFRunLoopRun + 927
    frame #18: 0x00007fff8a937bd8 CoreFoundation`CFRunLoopRunSpecific + 296
    frame #19: 0x00007fff8b77756f HIToolbox`RunCurrentEventLoopInMode + 235
    frame #20: 0x00007fff8b7772ea HIToolbox`ReceiveNextEventCommon + 431
    frame #21: 0x00007fff8b77712b HIToolbox`_BlockUntilNextEventMatchingListInModeWithFilter + 71
    frame #22: 0x00007fff8d06d9bb AppKit`_DPSNextEvent + 978
    frame #23: 0x00007fff8d06cf68 AppKit`-[NSApplication nextEventMatchingMask:untilDate:inMode:dequeue:] + 346
    frame #24: 0x00007fff8d062bf3 AppKit`-[NSApplication run] + 594
    frame #25: 0x00000001045857fd libqcocoa.dylib`___lldb_unnamed_function439$$libqcocoa.dylib + 2189
    frame #26: 0x00000001010108cd QtCore`QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) + 381
    frame #27: 0x000000010101378a QtCore`QCoreApplication::exec() + 346
    frame #28: 0x000000010000d859 Qt Creator`main + 22297
    frame #29: 0x00000001000054d4 Qt Creator`start + 52