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Re: Why doesn't combine like volatiles? (volatile_ok again, sorry!)

From: Robert Dewar <dewar at adacore dot com>
To: Richard Earnshaw <rearnsha at gcc dot gnu dot org>
Cc: Dave Korn <dave dot korn at artimi dot com>, 'Ian Lance Taylor' <ian at airs dot com>, gcc at gcc dot gnu dot org
Date: Tue, 22 Nov 2005 11:10:32 -0500
Subject: Re: Why doesn't combine like volatiles? (volatile_ok again, sorry!)
References: <SERRANO6qCvOeyYHeFu00000084@SERRANO.CAM.ARTIMI.COM> <1132674761.27134.177.camel@pc960.cambridge.arm.com>

Richard Earnshaw wrote:

AFAICT it is probably safe to do the combination provided (in addition
to the normal restrictions on combine) that:


I think this is a bad idea in practice, since volatile will be used
to describe memory mapped devices, and combining can completely
mess up the access. Yes, it is probably conforming, but it is
simply not a good idea to do this, and the gain is too small.

Follow-Ups:
- Re: Why doesn't combine like volatiles? (volatile_ok again, sorry!)
  - From: Mike Stump

References:
- RE: Why doesn't combine like volatiles? (volatile_ok again, sorry!)
  - From: Dave Korn
- RE: Why doesn't combine like volatiles? (volatile_ok again, sorry!)
  - From: Richard Earnshaw

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