struct Base {
	int result;
	virtual void Add(Ctrl &) { result = 1; }
};

struct Mid : public Base{
	virtual void Add(Ctrl &) { result = 2; }
	void Add(int)			{ result = 4; }
};

struct Top : public Mid{
	void Nothing()  { result = 0; }
};


GUI_APP_MAIN
{
	Label l;
	Top md;
	
	//option 1: << desired >>
	void (Top::* mfp)(Ctrl &) = &Top::Add;
	(md.*mfp)(l);
}