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Message-ID: <52EFD3C2.6030209@bo.infn.it>
Date: Mon, 03 Feb 2014 17:37:00 -0000
From: Graziano Servizi <Graziano.Servizi@bo.infn.it>
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How could this (included) very short code work?
It isn't a NOT SAFE conversion that made inside void fun?

How can the A pointer know about the B's member f() ?

I'm using gcc 4.8.2 on a Linux Fedora 19 system.

Thanks for your help.

G. Servizi

Code follows:

# include <iostream>
using namespace std;

  class A {/*omissis*/};
  class B : public A
   {/*omissis*/
    public:
    void f( ){cout<<"bye\n";}};

  void fun(A *a)
  {
  B *b = static_cast<B *>(a);
  b -> f( );
  }

  int main( )
  {
  A *a = new A;
  fun(a);
  }