undefined reference to vtable

[Chicken Blood Machine]

This usually happens when you've run qmake without having the Q_OBJECT macro. If you don't have that qmake won't add the right stuff to the make. So, once you've added it make needs to run again or when you link to the moc object it won't exist and will give you a vtable error. Run make clean, then qmake, the make again and see if that works

I don't think that any of the classes that he has declared there need the Q_OBJECT macro, do they?