* deadguysfrom@gmail.com:
> Ive got two classes in the same class hierarchy, and I want to find
> their common ancestor. Any idea how to do this?
>
> class A {};
> class B : public A {};
> class C : public B {};
> class D : public B {};
>
> I have pointers to C and D, I want pointers to B.

See the reply by Ian Collins else-thread.

If your enquiry is of a more academic, theoretical nature:

You can check whether the classes /have/ a common ancestor by using
static_cast, possibly combined with SFINAE.

You can go the opposite way, finding a pointer to the complete object
(of the most derived class), by using dynamic_cast<void*>, provided the
pointer you have is a pointer to an object of polymorphic class. This
is sometimes useful, e.g. for hashing. But it doesn't tell you what the
most derived class is, except you can get a run-time description.

You can not enumerate the class hierarchy by means of only language and
standard library functionality.

Cheers, & hth.,

- Alf

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