Virtual Default Destructors in C++

Question

I\'ve got a large set of inherited classes (criteria) which inherit from a base class (criterion). Here\'s criterion\'s code

class criterion
{
p         


        

Answer 1

One small change from what others have already answered:

Instead of

virtual void ~criterion() = 0;

the required version is:

    virtual ~criterion() {}  //Note: Removed void as destructors not allowed 
                             //  a return type

To know more about virtual destructor have a look at this link from FAQ When should my destructor be virtual?