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From: "Rod Pemberton" <dont_use_email@nohavenotit.com>
Newsgroups: comp.lang.forth
Subject: Re: RAFTS-like optimiser; progress report
Date: Sat, 14 Sep 2013 22:47:46 -0400
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On Fri, 13 Sep 2013 07:58:29 -0400, Anton Ertl  
<anton@mips.complang.tuwien.ac.at> wrote:

> 1) Stephen Pelc has suggested declaring a memory range read-only,
> which can solve this problem and more, so it is a more general
> solution to the same problem.

Without hardware support, implementing read-only memory using
read-write memory can be problematic.  E.g., it can require artificial
fixes like using paging to unmap memory.  Code checks to prevent
writes is probably the worst possible solution.  Yet, that would have
to be the solution used on many older platforms that have no ability
to make memory range read-only via programmatic methods or hardware.


Rod Pemberton