Re: [Boost-users] [Memory] Problems when calling virtual class function

Subject: Re: [Boost-users] [Memory] Problems when calling virtual class function
From: Marshall Clow (mclow.lists_at_[hidden])
Date: 2010-07-11 15:28:35

On Jul 11, 2010, at 12:17 PM, Janez Urevc wrote:

> Hello,
> 
> I am doing a research about Monte Carlo Tree Search efficiency on KBNK chess
> ending. I use framework and algorithm implementation in C++.  Since I had some
> memory leaks, that I couldn't manage to identify, I decided to try
> Boost's shared_ptr.
> I reorganized the whole thing to use it, but I encountered a problem,
> which I cannot
> solve.
> 
> The problem occurs, when I try to call class member function, which
> was declared
> "virtual" in super class. If I try to call functions, that are not
> redefined, everything
> works as expected. Ex.:
> 
> class Base{
>    public:
>        int val = 0;
>        virtual void fun(){ /* do something */}
> };
> 
> class Derived : public Base{
>    public:
>        void fun(){ /*redefined*/}
>        void fun1(){ /*not redefined*/}
> };

If you declare "fun" as virtual in the base class, it needs to be virtual in the derived class, too.
Many compilers will warn you about this.

-- Marshall