Problem with declaration of virtual function

From: Pierre Couderc (pierre_at_couderc.ccNOSPAM)
Date: 09/02/04 

Date: Thu, 02 Sep 2004 07:22:55 +0200

I have a problem with the declaration of virtual function. What do I do
wrong? Why the compiler (MS VC++ 6) says nothing?

It is very simple (see my comment below):

class A
{
public :
     A(){;}
};

class B : public A
{
public :
     B() : A() {;}
     virtual void bad() {;}
};

class C : public B
{
public :
     C() : B() {;}
     void bad() {;}
};

BOOL CVirtuApp::InitInstance()
{
     A* many[2];
     C* p = new C;
     ASSERT(_CrtIsValidHeapPointer(p));
     many[0] = p;
     ASSERT(_CrtIsValidHeapPointer(many[0])); // FAILS here
     ASSERT(many[0]== p); // OK;
...
}

When the ASSERT fails, I see that the paramter of CrtIsValidHeapPointer
is XXXX at first call and XXXX+4 at second call.

So what am I doing wrong?

Thank you in advance
Pierre Couderc

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