QwtPlot derived class

[Marco Trapanese]

you could debug and search the code that is responsible for thisaccess violation.

I wrote: "During startup [...]". That means no code is executed (better, no code visible through debug).

could you copy your *.cpp?
no errors for me in the declaration

No code in the cpp file, but the empty implementation of the constructor:

myplot::myplot(QWidget *parent): QwtPlot(parent) { }

myplot::myplot(QWidget *parent): QwtPlot(parent) { }

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I've just found I need to remove the Q_OBJECT macro. Without it runs.

Does anyone know why?

This is usually a problem of your build/runtime environment and has nothing to do with the code.

Maybe. But why removing the Q_OBJECT macro it works? It seems code related.