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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: virtual destructors
Date: 22 Apr 2003 17:23:33 -0400
Organization: The World Public Access UNIX, Brookline, MA
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Date: 2003-04-22T17:23:33-04:00
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Stephen Leake <Stephe.Leake@nasa.gov> writes:

> In general, the compiler can use different storage pools for each
> access type. 

True, but in the following example, there is only one access type:
CBase.  So both the "new" and the "Free" will be referring to the same
storage pool, namely CBase'Storage_Pool, so all is well.

> If you do:
> 
> A : CBase := new Derived'();
> 
> and then later:
> 
> Free (A);
> 
> The compiler might allocation from CDerived_Storage_Pool, and then
> deallocate from CBase_Storage_Pool. Very bad. 

To get in trouble, you have to do a type conversion.

- Bob