From: "Douglas A. Gwyn" <DAGwyn@null.net>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] how to avoid a memset() optimization
Date: Wed, 13 Nov 2002 10:15:43 +0000 [thread overview]
Message-ID: <3DD1DDD5.8090304@null.net> (raw)
In-Reply-To: <01974d0bd36314a7c8172b6eca15effe@plan9.bell-labs.com>
Russ Cox wrote:
> I disagree. It hurts readability and clarity, all
> to avoid a bug in gcc. If I asked it to zero the
> memory, then, damn it!, zero the memory.
It's not a bug, it's an allowed optimization (in the
absence of volatile qualification). The question is
where to draw the line for degree of optimization,
and the volatile qualifier was invented precisely to
draw the line at actually performing the coded
accesses to the variable whether or not the result
is further used in the program.
next prev parent reply other threads:[~2002-11-13 10:15 UTC|newest]
Thread overview: 91+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-11-13 0:31 Russ Cox
2002-11-13 1:26 ` Roman V. Shaposhnick
2002-11-13 10:15 ` Douglas A. Gwyn
2002-11-14 1:42 ` Roman V. Shaposhnick
2002-11-13 10:15 ` Douglas A. Gwyn [this message]
-- strict thread matches above, loose matches on Subject: below --
2003-01-06 10:47 nigel
2003-01-06 11:15 ` Geoff Collyer
2002-11-19 14:32 presotto
2002-11-20 7:24 ` Tomas
2002-11-20 16:38 ` Douglas A. Gwyn
2002-11-19 8:21 Fco.J.Ballesteros
2002-11-18 21:36 Joel Salomon
2002-11-18 20:42 Andrew Simmons
2002-11-18 14:19 C H Forsyth
2002-11-15 1:56 Dennis Ritchie
2002-11-15 10:51 ` Douglas A. Gwyn
2002-11-15 12:03 ` Boyd Roberts
2002-11-14 18:55 jmk
2002-11-14 22:23 ` Steve Kilbane
2002-11-14 18:17 presotto
2002-11-14 18:11 Joel Salomon
2002-11-14 18:26 ` William Josephson
2002-11-14 17:44 rog
2002-11-15 10:50 ` Douglas A. Gwyn
2002-11-14 17:28 Russ Cox
2002-11-14 16:47 presotto
2002-11-15 10:50 ` Douglas A. Gwyn
2002-11-15 16:51 ` William Josephson
2002-11-18 10:38 ` Douglas A. Gwyn
2002-11-18 12:34 ` Ronald G. Minnich
2002-11-19 7:38 ` Roman V. Shaposhnick
2002-11-20 9:47 ` Douglas A. Gwyn
2002-11-21 20:55 ` Roman V. Shaposhnick
2002-11-22 9:59 ` Douglas A. Gwyn
2003-01-06 10:18 ` Ralph Corderoy
2003-01-06 15:42 ` Sam
2003-01-06 15:49 ` Russ Cox
2003-01-06 15:58 ` David Presotto
2003-01-06 16:02 ` Sam
[not found] <nemo@plan9.escet.urjc.es>
2002-11-14 15:38 ` Fco.J.Ballesteros
2002-11-14 16:24 ` Scott Schwartz
2002-11-14 6:53 Russ Cox
2002-11-14 10:22 ` Douglas A. Gwyn
2002-11-14 13:20 ` Sam
2002-11-14 15:20 ` Scott Schwartz
2002-11-14 15:26 ` Boyd Roberts
2002-11-14 15:34 ` plan9
2002-11-14 15:59 ` Sam
2002-11-14 18:57 ` Steve Kilbane
2002-11-15 10:51 ` Douglas A. Gwyn
2002-11-14 15:50 ` Dan Cross
2002-11-14 17:21 ` Douglas A. Gwyn
2002-11-14 18:51 ` Dan Cross
2002-11-14 15:50 ` Douglas A. Gwyn
2002-11-19 7:20 ` Roman V. Shaposhnick
2002-11-14 2:48 Dennis Ritchie
2002-11-14 4:23 ` Ronald G. Minnich
2002-11-13 18:58 Rob `Commander' Pike
2002-11-13 14:40 C H Forsyth
2002-11-13 15:54 ` rob pike
2002-11-13 16:05 ` andrey mirtchovski
2002-11-13 16:32 ` Ronald G. Minnich
2002-11-14 10:21 ` Douglas A. Gwyn
2002-11-14 17:07 ` Ronald G. Minnich
2002-11-22 9:59 ` Clint Olsen
2002-11-13 16:56 ` William K. Josephson
2002-11-14 10:21 ` Douglas A. Gwyn
2002-11-14 16:48 ` William Josephson
2002-11-14 10:21 ` Douglas A. Gwyn
2002-11-14 14:46 ` Dan Cross
2002-11-14 16:59 ` Douglas A. Gwyn
2002-11-14 18:31 ` Tad Hunt
2002-11-15 10:50 ` Douglas A. Gwyn
2002-11-18 14:27 ` Aharon Robbins
2002-11-13 14:14 Skip Tavakkolian
2002-11-13 13:55 rog
2002-11-13 13:38 Skip Tavakkolian
2002-11-13 16:25 ` Boyd Roberts
2002-11-13 10:43 C H Forsyth
2002-11-14 10:21 ` Douglas A. Gwyn
2002-11-13 6:52 Geoff Collyer
2002-11-13 10:13 ` Boyd Roberts
2002-11-13 6:34 Andrew Simmons
2002-11-13 6:43 ` Doc Shipley
2002-11-13 1:47 Russ Cox
2002-11-13 10:16 ` Douglas A. Gwyn
2002-11-14 1:46 ` Roman V. Shaposhnick
2002-11-14 1:52 ` William Josephson
2002-11-14 6:42 ` Roman V. Shaposhnick
2002-11-13 0:20 presotto
2002-11-12 22:42 Roman V. Shaposhnick
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=3DD1DDD5.8090304@null.net \
--to=dagwyn@null.net \
--cc=9fans@cse.psu.edu \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).