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From: Kilgallen@SpamCop.net (Larry Kilgallen)
Newsgroups: comp.lang.ada
Subject: Re: Zero length Objects
Date: 1 Jul 2004 06:25:36 -0500
Organization: LJK Software
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 <PSFEc.50650$aJ3.17580@nwrdny02.gnilink.net> <2kh2leF2ct4hU1@uni-berlin.de>
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Date: 2004-07-01T06:25:36-05:00
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In article <2kh2leF2ct4hU1@uni-berlin.de>, "Nick Roberts" <nick.roberts@acm.org> writes:

> For the curious, the mechanism I suggested was that the compiler 'invents'
> unique encodings for access values that reference zero-size objects. An
> invented encoding can be any value that can be stored in an object of the
> access type which is guaranteed never to be the same as any valid address
> (or other invented value in scope), assuming the typical mechanism that an
> access value which references a nonzero-size object is simply its address.

I don't understand how one can guarantee such non-conflicting encodings
are possible on all architectures, particular when the compiler supports
operating system programming in Ada.