Re: inhibit compiler warning C4624 for a class hierarchy

Ben Voigt <rbv@xxxxxxxxxxxxx> wrote:
Every instance will be
freed by the base class destructor and operator delete, regardless of
specific type.

It doesn't work this way. Any class must have a destructor before you
can create (or, to be exact, destroy) an instance of it. It could be
trivial, it could be private, it could be implicitly defined, but a
class must have one. From the standard:

12.4/5 An implicitly-declared destructor is implicitly defined when it
is used to destroy an object of its class type (3.7). A program is
ill-formed if the class for which a destructor is implicitly defined
has:
....
- a base class with an inaccessible destructor.

The moment you use delete on the pointer of the derived type (whether in
the base class or otherwise) your program becomes ill-formed.
--
With best wishes,
Igor Tandetnik

With sufficient thrust, pigs fly just fine. However, this is not
necessarily a good idea. It is hard to be sure where they are going to
land, and it could be dangerous sitting under them as they fly
overhead. -- RFC 1925


.

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