Why is my destructor never called?

Question

I have a base class A and a derived class B:

class A
{
public:
    virtual f();
};

class B : public A
{
public:
     B()
     {
         p = new char [100];
            


        

Answer 1

If your variable is of type A it doesn't have a virtual destructor and so it won't look at the actual runtime type of the object to determine it needs to call the desstructor

Add an empty destructor to A

virtual ~A() {}

and that should fix it.

In general you need to do this on any class that can possibly be used as a base class.