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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
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Subject: Re: 80286 protected mode
Date: Fri, 18 Oct 2024 05:39:02 -0700
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Terje Mathisen <terje.mathisen@tmsw.no> writes:

[ISA support for copying possibly overlapping regions of memory]

[Separately, what is possible to do in portable standard C]

> [...] I really don't think any of us really disagree, it is just
> that we have been discussing two (mostly) orthogonal issues.

I would summarize the string of conversations as follows.

It started with talking about what is or is not possible in
"standard C", by which is meant C that does not rely on any
implementation-specific behavior.  (Topic A.)

The discussion shifted after a comment about how to provide
architectual support for copying one region of memory to
another, where the areas of memory might overlap.  (Topic B.)

After the introduction of Topic B, most of the subsequent
conversation either ignored Topic A or conflated the two
topics.

The key point is that Topic B has nothing to do with Topic A,
and vice versa.  It's like asking why it's colder in the
mountains than it is in the summer:  both parts have something
to do with temperature, but in spite of that there is no
meaningful relationship between them.