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From: Robert A Duff <bobduff@TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Comparing Access Types
Date: Fri, 10 Nov 2017 11:05:42 -0500
Organization: The World Public Access UNIX, Brookline, MA
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Date: 2017-11-10T11:05:42-05:00
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"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:

> You could have two segments mapped to the same physical memory.

No, the implementation would not allow that to happen.

The fact that the hardware allows it is irrelevant.
In fact, nonsegmented machines can do the same thing
-- you can map two virtual pages to the same physical
address.  If you want "=" on pointers to work, then
simply don't do that.

>... Then you
> may have two unequal segmented addresses pointing to the same physical
> memory unit and so "=" will lie.

If "=" lies, then the Ada implementation is simply wrong.

- Bob