From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham
	autolearn_force=no version=3.4.4
X-Google-Language: ENGLISH,ASCII-7-bit
X-Google-Thread: 103376,de1c23707584fc3c
X-Google-Attributes: gid103376,public
X-Google-ArrivalTime: 2003-04-22 14:21:30 PST
Path: 
 archiver1.google.com!news1.google.com!newsfeed.stanford.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!newsfeed.icl.net!newsfeed.fjserv.net!kibo.news.demon.net!news.demon.co.uk!demon!not-for-mail
From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: virtual destructors
Date: 22 Apr 2003 21:19:42 +0100
Organization: Pushface
Sender: simon@smaug.pushface.org
Message-ID: <x7vwuhme141.fsf@smaug.pushface.org>
References: <b83ivk$29l$1@news.onet.pl> <u1xzuehed.fsf@nasa.gov>
 <b83l69$7bk$1@news.onet.pl> <b83o2t$gd8$1@news.onet.pl>
 <u3ckacuwv.fsf@nasa.gov> <x7vznmize1t.fsf@smaug.pushface.org>
 <ubryyb90o.fsf@nasa.gov>
NNTP-Posting-Host: pogner.demon.co.uk
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
X-Trace: news.demon.co.uk 1051046490 2299 62.49.19.209 (22 Apr 2003 21:21:30
 GMT)
X-Complaints-To: abuse@demon.net
NNTP-Posting-Date: Tue, 22 Apr 2003 21:21:30 +0000 (UTC)
User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.1
Xref: archiver1.google.com comp.lang.ada:36373
Date: 2003-04-22T21:19:42+01:00
List-Id: <comp.lang.ada>

Stephen Leake <Stephe.Leake@nasa.gov> writes:

> Simon Wright <simon@pushface.org> writes:
> 
> > Stephen Leake <Stephe.Leake@nasa.gov> writes:
> > 
> > > You also need to ensure that both access types use the same storage
> > > pool. Something like:
> > > 
> > > for CDerived'Storage_Pool use CBase'Storage_Pool.
> > 
> > I don't see why? there was no attempt I could see to convert between
> > the classwide pointer types?
> 
> In general, the compiler can use different storage pools for each
> access type. 
> 
> 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. 

Indeed, I hadn't spotted that particular problem (I was looking at the
procedures, not the main program). Sorry.