Re: inhibit compiler warning C4624 for a class hierarchy


"Igor Tandetnik" <itandetnik@xxxxxxxx> wrote in message
news:eERgQSNNHHA.1240@xxxxxxxxxxxxxxxxxxxxxxx
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
Non-virtual destruction from the base class doesn't use this
implicitly-declared destructor, so this rule doesn't apply.

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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