In Qt, the Q_PROPERTY macro is an empty macro that is used only by moc. The macro declares a *public* property. It doesn't matter whether it appears in the private, protected, or public sections of the class - the property is always public.

This is a regression from 1.8.7, most likely caused by the fix to bug 734245.

For example, taken from qobject.h from Qt 5:

class Q_CORE_EXPORT QObject
{
    Q_OBJECT
    Q_PROPERTY(QString objectName READ objectName WRITE setObjectName NOTIFY objectNameChanged)
    ...
};

This declares a *public* property, in spite of appearing in a private section of the class. Neither does this macro change the visibility of the succeeding members: its expansion is empty. It's not like the Q_OBJECT macro which *does* change the visibility of the succeeding members to private.