Re: A simple problem with an abstract class...

"Victor Bazarov" <>
Tue, 20 Mar 2007 20:53:54 -0400
Jim Brown wrote:

I'm working an a large legacy app that is built with Makefiles using
the Microsoft Visual Studio 8/VC/BIN/cl.EXE compiler. I have a crazy
problem that I'm hoping someone has seen before. I've included a
simplified version of the problem that runs fine in a VC++ console
test project. The project crashes if I instantiate an object of class
B without commenting out the call to the pure virtual function x() in
A::doIt(); Naturally, B deals with objects derived from A.

Thanks for taking a look.

Don't mention it.

I've taken a look and cannot really say anything. You omitted too
much stuff to make any conclusions.

class A



     void doIt() { x(); }

     virtual void x() = 0;

     virtual ~A() {}


class B



     B() {}

     void push(A* pA) { ... }

     A* pop() { A* pA = ...; return pA; }

What's in those dots?

Apparently, whatever you have in those dots screws it up.

     void tryIt() { A* pA = pop(); pA->doIt(); }


Please remove capital 'A's when replying by e-mail
I do not respond to top-posted replies, please don't ask

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