Re: Class Destructor doesn't destroy?

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"Gerry Hickman" <gerry666uk@xxxxxxxxxxxxxxxx> wrote in message
news:uER06v1XIHA.536@xxxxxxxxxxxxxxxxxxxx
If I instantiate a Class using operator new, I can destroy it with
operator delete, but if I instantiate it without operator new, I don't
seem to be able to destroy it until it goes out of scope - manually
calling the destructor doesn't completely destroy it.

More precisely, your program exhibits undefined behavior under C++
stanadard 3.8/8:

If a program ends the lifetime of an object of type T with static
(3.7.1) or automatic (3.7.2) storage duration and if T has a non-trivial
destructor, the program must ensure that an object of the original type
occupies that same storage location when the implicit destructor call
takes place; otherwise the behavior of the program is undefined.

"Undefined behavior" here means the program can do anything, including
calling the destructor twice. See also

http://www.faqs.org/docs/jargon/N/nasal-demons.html

--
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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