QQC2: Using ComboBox crashes

1  QQmlListModel::index                     qqmllistmodel.cpp         2145 0x7ffb8c6840a6 
2  QQuickComboBox::count                    qquickcombobox.cpp        919  0x7ffb843361f5 
3  QQuickComboBox::componentComplete        qquickcombobox.cpp        2052 0x7ffb84339531 
4  QQmlObjectCreator::finalize              qqmlobjectcreator.cpp     1467 0x7ffb88cd4417 
5  QQmlComponentPrivate::complete           qqmlcomponent.cpp         990  0x7ffb88b752da 
6  QQmlComponentPrivate::completeCreate     qqmlcomponent.cpp         1081 0x7ffb88b740ac 
7  QQmlComponent::completeCreate            qqmlcomponent.cpp         1068 0x7ffb88b71e72 
8  QQmlComponent::create                    qqmlcomponent.cpp         825  0x7ffb88b71bce 
9  QQmlApplicationEnginePrivate::finishLoad qqmlapplicationengine.cpp 154  0x7ffb88cc255c 
10 QQmlApplicationEnginePrivate::startLoad  qqmlapplicationengine.cpp 139  0x7ffb88cc1fe1 
11 QQmlApplicationEngine::load              qqmlapplicationengine.cpp 283  0x7ffb88cc126d 
12 main                                     main.cpp                  25   0x7ff65cb0333f 

parent	0x0	QModelIndex*
this	@0xc9641efaf8	QStringListModel