No way to call a custom setter for a QProperty outside of QObject hierarchy

Normally if we need to use custom setter (that is doing smth more complicated than simply calling operator=()), we need to use Q_OBJECT_COMPAT_PROPERTY macro.

However this macro does not work outside of QObject or QObjectPrivate hierarchy.

I have identified at least 2 places, where the property is located outside of the hierarchy, and the custom setters are used:

• QObject and its objectName property.
• Most of the properties in QCoreApplication.