Re: C2614: Inheritance question

David Wilkinson <>
Mon, 08 Oct 2007 09:03:46 -0400
Jack wrote:

Hello Uli,
Thanks for the tips... But here I am with another question
class CPerson : public CPathfinder
    bool Create(...);
class CSupervisor : public CPerson
     virtual bool Create (...);

In this case, should I put the implementation code in CPerson with each
function declared as virtual and in CSupervisor as non-virtual, or the other
way round, implement code in CSupervisor and declared the derived methods as
virtual while CPerson as non-virtual (illustrated in the above snippet). I
tried the later method but with no errors reported, so I assumed that was
correct. But just in doubt if my design is correct or not?


Your code above is conceptually wrong, and may produce a warning on some

Do like this

class CPerson : public CPathfinder
     virtual bool Create(...) = 0; // pure virtual

class CSupervisor : public CPerson
      virtual bool Create (...);

bool CSupervisor::Create(...)
    return true;

The "virtual" keyword can be omitted in the derived class (CSupervisor),
but IMHO this is bad C++ style.

Now if you do

CPerson* pPerson = new CSupervisor;

then CSupervisor::Create() gets called. If Create() were not declared
virtual in CPerson, the compiler would have no way to know that it
should call the derived version.

David Wilkinson
Visual C++ MVP

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