@c64zottel said in How to use Q_DISABLE_COPY( class ) without ctor?: The ctor is simply empty It is not. in fact it calls the QObject constructor that does a lot of stuff. removing it while leaving the Q_DISABLE_COPY prevents the compiler from creating a default constructor (which would be wrong anyway). Now we have 2 possible solutions: If your InputDeviceConfigurator uses signals and slots or defines properties then your only choice is to explicitly declare the constructor and pass the parent explicit InputDeviceConfigurator(QObject *parent = Q_NULLPTR) : QObject(parent){} if InputDeviceConfigurator does not uses signals and slots nor defines properties then lose the QObject inheritance altogether and use multiple inheritance for the derived classes. Just to make the point clear: you don't "remove the constructor". see this table @c64zottel said in How to use Q_DISABLE_COPY( class ) without ctor?: the auto generate ctor would be fine too. In cases (this one is not one of them) in which the default costructor is what you want just use =default