Rule Definition
If an object is handled through a pointer to its base class (handled through a generic interface that is certainly a major objective in object-oriented programming), memory and stability problems occur when the object is to be deleted and when the object has been created on the heap with new. If the pointer is to the base class, the compiler can only know to call the base-class version of the destructor during the delete. Any memory clean up or functional actions that must take place when derived classes are deleted will not take place provoking memory leaks, resource losses and stability issues.

Remediation
Add a virtual destructor to the base class.

Violation Code Sample

class CParent
{
    CParent() { ... }
    ~CParent() { ... }
};

class CDerived : public CParent
{
...
};

Fixed Code Sample

class CParent
{
    CParent() { ... }
    virtual ~CParent() { ... }
};

class CDerived : public CParent
{
...
};

Bruce Eckel's "Thinking in C++" http://www.cs.huji.ac.il/labs/parallel/Docs/C++/Guide/tic0161.html Bruce Eckel's "Thinking in C++" http://www.cs.huji.ac.il/labs/parallel/Docs/C++/Guide/