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From: Robert A Duff <bobduff@world.std.com>
Subject: Re: Ada GC (was Re: Ammo-zilla)
Date: 1999/11/09
Message-ID: <wcczowniqoc.fsf@world.std.com>#1/1
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Sender: bobduff@world.std.com (Robert A Duff)
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Organization: The World Public Access UNIX, Brookline, MA
Newsgroups: comp.lang.ada
Date: 1999-11-09T00:00:00+00:00
List-Id: <comp.lang.ada>

"Vladimir Olensky" <vladimir_olensky@yahoo.com> writes:

> Robert Dewar wrote in message <7vvroo$grr$1@nnrp1.deja.com>...
> >Again you miss my point, unless you segregate memory with
> >hardware memory protect, allowing unchecked conversion, and
> >hence address calculations, anywhere, can damage data structures
> >anywhere. I am NOT talking about bugs in the GC implementation
> >itself.

And crossing a hardware protection boundary once for every "new" would
be prohibitively expensive (unless you designed the hardware
specifically to support such a thing -- even then, it would be
expensive).

> It just never come to my mind that someone (one the client's side)
> could try to do something (using unchecked conversions ) for anything
> that is behind that protection wall  (for me it is a crazy idea).

Bugs are not caused by people *trying* to do something -- they happen by
accident!

- Bob