Valgrind: invalid memory read in QQmlContextData::emitDestruction()

The attached minimal example leads to invalid memory read:

==4433== Invalid read of size 8 ==4433== at 0x63F470B: QQmlContextData::emitDestruction() (qqmlcontext.cpp:568) ==4433== by 0x63F4F40: QQmlContextData::invalidate() (qqmlcontext.cpp:576) ==4433== by 0x63D1D92: QQmlPrivate::qdeclarativeelement_destructor(QObject*) (qqmlengine.cpp:751) ==4433== by 0x509C5BB: ~QQmlElement (qqmlprivate.h:107) ==4433== by 0x509C5BB: QQmlPrivate::QQmlElement<QQuickItem>::~QQmlElement() (qqmlprivate.h:108) ==4433== by 0x513810E: QQuickView::~QQuickView() (qquickview.cpp:214) ==4433== by 0x5138258: QQuickView::~QQuickView() (qquickview.cpp:216) ==4433== by 0x408F4C: cleanup (qscopedpointer.h:60) ==4433== by 0x408F4C: ~QScopedPointer (qscopedpointer.h:107) ==4433== by 0x408F4C: main (main.cpp:640) ==4433== Address 0x13d5bd30 is 112 bytes inside a block of size 184 free'd ==4433== at 0x4C2F602: operator delete(void*, unsigned long) (vg_replace_malloc.c:595) ==4433== by 0x63F4E87: QQmlContextData::destroy() (qqmlcontext.cpp:676) ==4433== by 0x63F4F1D: QQmlContext::~QQmlContext() (qqmlcontext.cpp:221) ==4433== by 0x63F4F28: QQmlContext::~QQmlContext() (qqmlcontext.cpp:222) ==4433== by 0x154A8606: QQuickStackElement::~QQuickStackElement() (qquickstackelement.cpp:111) ==4433== by 0x154A8790: QQuickStackElement::~QQuickStackElement() (qquickstackelement.cpp:112) ==4433== by 0x154AEBEE: void qDeleteAll<QQuickStackElement* const*>(QQuickStackElement* const*, QQuickStackElement* const*) (qalgorithms.h:320) ==4433== by 0x154AD04F: qDeleteAll<QStack<QQuickStackElement*> > (qalgorithms.h:328) ==4433== by 0x154AD04F: QQuickStackView::clear(QQuickStackView::Operation) (qquickstackview.cpp:933) ==4433== by 0x154D4CDE: QQuickStackView::qt_static_metacall(QObject*, QMetaObject::Call, int, void*) (moc_qquickstackview_p.cpp:271) ==4433== by 0x154D5520: QQuickStackView::qt_metacall(QMetaObject::Call, int, void) (moc_qquickstackview_p.cpp:454) ==4433== by 0x692033D: QMetaObject::metacall(QObject, QMetaObject::Call, int, void*) (qmetaobject.cpp:316) ==4433== by 0x6430EEA: QQmlObjectOrGadget::metacall(QMetaObject::Call, int, void) const (qqmlpropertycache.cpp:1770) ==4433== by 0x62E8FC9: CallMethod(QQmlObjectOrGadget const&, int, int, int, int, QV4::ExecutionEngine*, QV4::CallData*, QMetaObject::Call) (qv4qobjectwrapper.cpp:1295) ==4433== by 0x62E95A7: CallPrecise(QQmlObjectOrGadget const&, QQmlPropertyData const&, QV4::ExecutionEngine*, QV4::CallData*, QMetaObject::Call) (qv4qobjectwrapper.cpp:1557) ==4433== by 0x62E9966: CallOverloaded(QQmlObjectOrGadget const&, QQmlPropertyData const&, QV4::ExecutionEngine*, QV4::CallData*, QQmlPropertyCache const*, QMetaObject::Call) (qv4qobjectwrapper.cpp:1631) ==4433== by 0x62EA178: QV4::QObjectMethod::callInternal(QV4::Value const*, QV4::Value const*, int) const (qv4qobjectwrapper.cpp:2120) ==4433== by 0x62EA1A2: QV4::QObjectMethod::virtualCall(QV4::FunctionObject const*, QV4::Value const*, QV4::Value const*, int) (qv4qobjectwrapper.cpp:2055) ==4433== by 0x6309AF1: call (qv4functionobject_p.h:202) ==4433== by 0x6309AF1: QV4::Moth::VME::interpret(QV4::CppStackFrame*, QV4::ExecutionEngine*, char const*) (qv4vme_moth.cpp:737) ==4433== by 0x6310144: QV4::Moth::VME::exec(QV4::CppStackFrame*, QV4::ExecutionEngine*) (qv4vme_moth.cpp:447) ==4433== by 0x6270DA5: QV4::Function::call(QV4::Value const*, QV4::Value const*, int, QV4::ExecutionContext const*) (qv4function.cpp:68) ==4433== by 0x645F9BA: QQmlJavaScriptExpression::evaluate(QV4::CallData*, bool*) (qqmljavascriptexpression.cpp:211) ==4433== by 0x63F9FAE: QQmlBoundSignalExpression::evaluate(void*) (qqmlboundsignal.cpp:225) ==4433== by 0x63FA387: QQmlBoundSignal_callback(QQmlNotifierEndpoint, void*) (qqmlboundsignal.cpp:358) ==4433== by 0x643B904: QQmlNotifier::emitNotify(QQmlNotifierEndpoint, void*) (qqmlnotifier.cpp:104) ==4433== by 0x63D3307: QQmlData::signalEmitted(QAbstractDeclarativeData, QObject*, int, void*) (qqmlengine.cpp:883) ==4433== by 0x694770F: QMetaObject::activate(QObject, int, int, void*) (qobject.cpp:3676) ==4433== by 0x6948062: QMetaObject::activate(QObject, QMetaObject const*, int, void*) (qobject.cpp:3657) ==4433== by 0x655744D: QQmlComponentAttached::destruction() (moc_qqmlcomponentattached_p.cpp:148) ==4433== by 0x63F46D0: QQmlContextData::emitDestruction() (qqmlcontext.cpp:562) ==4433== by 0x63F470A: QQmlContextData::emitDestruction() (qqmlcontext.cpp:567) ==4433== by 0x63F470A: QQmlContextData::emitDestruction() (qqmlcontext.cpp:567) ==4433== by 0x63F470A: QQmlContextData::emitDestruction() (qqmlcontext.cpp:567) ==4433== by 0x63F4F40: QQmlContextData::invalidate() (qqmlcontext.cpp:576) ==4433== by 0x63D1D92: QQmlPrivate::qdeclarativeelement_destructor(QObject) (qqmlengine.cpp:751) ==4433== by 0x509C5BB: ~QQmlElement (qqmlprivate.h:107) ==4433== by 0x509C5BB: QQmlPrivate::QQmlElement<QQuickItem>::~QQmlElement() (qqmlprivate.h:108) ==4433== by 0x513810E: QQuickView::~QQuickView() (qquickview.cpp:214) ==4433== by 0x5138258: QQuickView::~QQuickView() (qquickview.cpp:216) ==4433== by 0x408F4C: cleanup (qscopedpointer.h:60) ==4433== by 0x408F4C: ~QScopedPointer (qscopedpointer.h:107) ==4433== by 0x408F4C: main (main.cpp:640) ==4433== Block was alloc'd at ==4433== at 0x4C2E4B6: operator new(unsigned long) (vg_replace_malloc.c:344) ==4433== by 0x63F48FC: QQmlContext::QQmlContext(QQmlContext*, QObject*) (qqmlcontext.cpp:191) ==4433== by 0x154A8E86: QQuickStackElement::load(QQuickStackView*) (qquickstackelement.cpp:168) ==4433== by 0x154B0D67: QQuickStackViewPrivate::pushElements(QList<QQuickStackElement*> const&) (qquickstackview_p.cpp:178) ==4433== by 0x154AB842: QQuickStackView::push(QQmlV4Function*) (qquickstackview.cpp:601) ==4433== by 0x154D4D7E: QQuickStackView::qt_static_metacall(QObject*, QMetaObject::Call, int, void*) (moc_qquickstackview_p.cpp:281) ==4433== by 0x154D5520: QQuickStackView::qt_metacall(QMetaObject::Call, int, void) (moc_qquickstackview_p.cpp:454) ==4433== by 0x692033D: QMetaObject::metacall(QObject, QMetaObject::Call, int, void*) (qmetaobject.cpp:316) ==4433== by 0x6430EEA: QQmlObjectOrGadget::metacall(QMetaObject::Call, int, void) const (qqmlpropertycache.cpp:1770) ==4433== by 0x62EA14C: QV4::QObjectMethod::callInternal(QV4::Value const, QV4::Value const*, int) const (qv4qobjectwrapper.cpp:2112) ==4433== by 0x62EA1A2: QV4::QObjectMethod::virtualCall(QV4::FunctionObject const*, QV4::Value const*, QV4::Value const*, int) (qv4qobjectwrapper.cpp:2055) ==4433== by 0x6309AF1: call (qv4functionobject_p.h:202) ==4433== by 0x6309AF1: QV4::Moth::VME::interpret(QV4::CppStackFrame*, QV4::ExecutionEngine*, char const*) (qv4vme_moth.cpp:737) ==4433== by 0x6310144: QV4::Moth::VME::exec(QV4::CppStackFrame*, QV4::ExecutionEngine*) (qv4vme_moth.cpp:447) ==4433== by 0x6270DA5: QV4::Function::call(QV4::Value const*, QV4::Value const*, int, QV4::ExecutionContext const*) (qv4function.cpp:68) ==4433== by 0x645F9BA: QQmlJavaScriptExpression::evaluate(QV4::CallData*, bool*) (qqmljavascriptexpression.cpp:211) ==4433== by 0x63F9FAE: QQmlBoundSignalExpression::evaluate(void*) (qqmlboundsignal.cpp:225) ==4433== by 0x63FA387: QQmlBoundSignal_callback(QQmlNotifierEndpoint, void*) (qqmlboundsignal.cpp:358) ==4433== by 0x643B904: QQmlNotifier::emitNotify(QQmlNotifierEndpoint, void*) (qqmlnotifier.cpp:104) ==4433== by 0x63D3307: QQmlData::signalEmitted(QAbstractDeclarativeData, QObject*, int, void*) (qqmlengine.cpp:883) ==4433== by 0x694770F: QMetaObject::activate(QObject, int, int, void*) (qobject.cpp:3676) ==4433== by 0x6948062: QMetaObject::activate(QObject, QMetaObject const*, int, void*) (qobject.cpp:3657) ==4433== by 0x655742D: QQmlComponentAttached::completed() (moc_qqmlcomponentattached_p.cpp:142) ==4433== by 0x6480765: QQmlObjectCreator::finalize(QQmlInstantiationInterrupt&) (qqmlobjectcreator.cpp:1400) ==4433== by 0x63EB9C4: QQmlComponentPrivate::complete(QQmlEnginePrivate, QQmlComponentPrivate::ConstructionState*) (qqmlcomponent.cpp:935) ==4433== by 0x63EBAED: QQmlComponentPrivate::completeCreate() (qqmlcomponent.cpp:971) ==4433== by 0x63EBB72: QQmlComponent::completeCreate() (qqmlcomponent.cpp:963) ==4433== by 0x63EB779: QQmlComponent::create(QQmlContext*) (qqmlcomponent.cpp:797) ==4433== by 0x408E06: main (main.cpp:634)