Valgrind reports read on deleted memory on the following code

Valgrind says

==19211== Invalid read of size 8
==19211== at 0x58CA2C9: QRecursionWatcher<QQmlObjectCreatorSharedState, &QQmlObjectCreatorSharedState::recursionNode>::~QRecursionWatcher() (qrecursionwatcher_p.h:94)
==19211== by 0x58C8931: QQmlObjectCreator::finalize(QQmlInstantiationInterrupt&) (qqmlobjectcreator.cpp:1244)
==19211== by 0x583C938: QQmlIncubatorPrivate::incubate(QQmlInstantiationInterrupt&) (qqmlincubator.cpp:357)
==19211== by 0x583BD7A: QQmlEnginePrivate::incubate(QQmlIncubator&, QQmlContextData*) (qqmlincubator.cpp:95)
==19211== by 0x5838A8F: QQmlComponent::create(QQmlIncubator&, QQmlContext*, QQmlContext*) (qqmlcomponent.cpp:1072)
==19211== by 0x5104805: QQuickLoaderPrivate::_q_sourceLoaded() (qquickloader.cpp:721)
==19211== by 0x5103F52: QQuickLoaderPrivate::load() (qquickloader.cpp:604)
==19211== by 0x5104A22: QQuickLoader::componentComplete() (qquickloader.cpp:813)
==19211== by 0x58C859C: QQmlObjectCreator::finalize(QQmlInstantiationInterrupt&) (qqmlobjectcreator.cpp:1202)
==19211== by 0x58384A1: QQmlComponentPrivate::complete(QQmlEnginePrivate*, QQmlComponentPrivate::ConstructionState*) (qqmlcomponent.cpp:932)
==19211== by 0x5838585: QQmlComponentPrivate::completeCreate() (qqmlcomponent.cpp:968)
==19211== by 0x5838537: QQmlComponent::completeCreate() (qqmlcomponent.cpp:961)
==19211== Address 0x214dff58 is 104 bytes inside a block of size 112 free'd
==19211== at 0x4C2C2BC: operator delete(void*) (vg_replace_malloc.c:503)
==19211== by 0x58C2095: QQmlObjectCreator::~QQmlObjectCreator() (qqmlobjectcreator.cpp:156)
==19211== by 0x583B64C: QScopedPointerDeleter<QQmlObjectCreator>::cleanup(QQmlObjectCreator*) (qscopedpointer.h:62)
==19211== by 0x583AE48: QScopedPointer<QQmlObjectCreator, QScopedPointerDeleter<QQmlObjectCreator> >::reset(QQmlObjectCreator*) (qscopedpointer.h:157)
==19211== by 0x583C321: QQmlIncubatorPrivate::clear() (qqmlincubator.cpp:185)
==19211== by 0x583CF3D: QQmlIncubator::clear() (qqmlincubator.cpp:577)
==19211== by 0x510324D: QQuickLoaderPrivate::clear() (qquickloader.cpp:95)
==19211== by 0x5103C01: QQuickLoader::setSourceComponent(QQmlComponent*) (qquickloader.cpp:472)
==19211== by 0x51055F6: QQuickLoader::qt_metacall(QMetaObject::Call, int, void**) (moc_qquickloader_p.cpp:280)
==19211== by 0x7244576: QMetaObject::metacall(QObject*, QMetaObject::Call, int, void**) (qmetaobject.cpp:308)
==19211== by 0x5832FD4: QQmlPropertyPrivate::write(QObject*, QQmlPropertyData const&, QVariant const&, QQmlContextData*, QFlags<QQmlPropertyPrivate::WriteFlag>) (qqmlproperty.cpp:1338)
==19211== by 0x58327BE: QQmlPropertyPrivate::writeValueProperty(QObject*, QQmlPropertyData const&, QVariant const&, QQmlContextData*, QFlags<QQmlPropertyPrivate::WriteFlag>) (qqmlproperty.cpp:1246)

on the attached code.

I know the code is a bit evil, but it's just a simplification of the real code we have were it kind of makes more sense.