Hi,

    Please look at the code below,

#include <iostream.h>

class A {
public:
        A() { cout << "In A CTOR"<< endl;}
        ~A() { cout << "In A DTOR"<< endl;}
        virtual void x() {
                cout << "In A's X" << endl;
        }
};

class B : public A{
public:
        B() { cout << "In B CTOR"<< endl;}
        ~B() { cout << "In B DTOR"<< endl;}
        void x() {
                cout << "In B's X" << endl;
        }
        void y() {
                cout << "IN Y" << endl;
        }
};


void main() {

        B* bb = (B*)new A;
        bb->y();
        delete bb;

 /*
   // The output is the same in this case as well

   //      B* bb = reinterpret_cast<B*>(new A);
   //      B* bb = static_cast<B*>(new A);
   bb->y();
        delete bb;
 */


}

    The output generated is as follows,

In A CTOR
IN Y
In B DTOR
In A DTOR

 Shouldn't at least the cast operator take care of this??????

 - Thanks
 - Raveendran V.


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>  Shouldn't at least the cast operator take care of this??????

If B is derived from A, and you write

        B* bb = (B*)new A;

the effect is undefined.

The result of "new A" is a pointer to an A object, not a pointer
to a B object, and casting the pointer won't change that.

--
Andrew Koenig, ark@research.att.com, http://www.research.att.com/info/ark

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