QPromise destructor doesn't transition to canceled state if it wasn't start()-ed

The docs for QPromise::~QPromise() state that the promise transitions to a canceled state on destruction, unless finish() is called.

However, if the promise is never start()-ed but it gets deleted, then the associated future never gets canceled, and as a result QFuture::waitForFinished() will never return, ever.

Is this intended behavior? I believe that if a QPromise is never started but deleted, it should still somehow signal to associated futures which call waitForFinished() to return.