linux-sparse.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Segher Boessenkool <segher@kernel.crashing.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@ftp.linux.org.uk>,
	linux-kernel@vger.kernel.org, linux-sparse@vger.kernel.org
Subject: Re: [PATCH 16/16] fix handling of integer constant expressions
Date: Sun, 24 Jun 2007 21:40:06 +0200	[thread overview]
Message-ID: <1a25667a20e43a072f733a3ec2b8e79d@kernel.crashing.org> (raw)
In-Reply-To: <alpine.LFD.0.98.0706241203530.3593@woody.linux-foundation.org>

>> Why?  I'd say it's not better than BUILD_BUG_ON_ZERO() use
>> instead of that ?:
>
> Oh, _that_ part I have no problem with. It's more that it seems that 
> the
> gcc optimization is ok at least as an extension.

Sure, but it's not an extension (yet), but an implementation
side-effect; it would have to be (semi-formally) defined in
the manual to be an extension.  Until that happens, anyone
using this "feature" risks haven his code broken at any time
(or, rather, his code already was broken but he didn't know
it).

See gcc.gnu.org/PR456 for more discussion.  Yes it's an old
bug...


Segher

  reply	other threads:[~2007-06-24 19:40 UTC|newest]

Thread overview: 50+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-06-24  8:05 [PATCH 16/16] fix handling of integer constant expressions Al Viro
2007-06-24 17:47 ` Al Viro
2007-06-24 18:04   ` Linus Torvalds
2007-06-24 18:35     ` Al Viro
2007-06-24 19:04       ` Linus Torvalds
2007-06-24 19:40         ` Segher Boessenkool [this message]
2007-06-24 20:38           ` Al Viro
2007-06-24 21:42             ` Neil Booth
2007-06-24 23:07               ` Al Viro
2007-06-25  6:16               ` Segher Boessenkool
2007-06-25  5:31             ` Josh Triplett
2007-06-25 19:55               ` Al Viro
2007-06-26  3:12                 ` Josh Triplett
2007-06-26 22:10               ` Al Viro
2007-06-26 22:11                 ` Al Viro
2007-06-26 23:32                   ` Neil Booth
2007-06-27  0:18                     ` Al Viro
2007-06-27  0:25                       ` Linus Torvalds
2007-06-27  0:37                         ` Al Viro
2007-06-27  0:29                       ` Derek M Jones
2007-06-27  0:41                         ` Al Viro
2007-06-27 11:52                       ` Neil Booth
2007-06-27 12:19                         ` Al Viro
2007-06-27 12:26                           ` Neil Booth
2007-06-27 12:37                             ` Al Viro
2007-06-27 12:10                   ` Neil Booth
2007-06-27 12:30                     ` Al Viro
2007-06-27 12:59                       ` Neil Booth
2007-06-27 13:18                         ` Al Viro
2007-06-27 13:35                           ` Neil Booth
2007-06-27 14:06                             ` Al Viro
2007-06-27 15:54                               ` Al Viro
2007-06-27 14:50                           ` Josh Triplett
2007-06-27 14:59                             ` Al Viro
2007-06-27 16:19                     ` Linus Torvalds
2007-06-27 16:34                       ` Josh Triplett
2007-06-27 17:25                         ` Al Viro
2007-06-27 17:29                       ` Al Viro
2007-06-27 17:45                         ` Linus Torvalds
2007-06-27 18:04                           ` Al Viro
2007-06-27 22:50                       ` Neil Booth
2007-06-28  9:08                       ` Segher Boessenkool
2007-06-26 22:49                 ` Josh Triplett
2007-06-25  6:13             ` Segher Boessenkool
2007-06-24 19:59         ` Al Viro
2007-06-24 18:07   ` Arnd Bergmann
2007-06-24 19:10     ` Al Viro
2007-06-24 18:18   ` Segher Boessenkool
2007-06-24 18:44     ` Al Viro
2007-06-24 19:09       ` Segher Boessenkool

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=1a25667a20e43a072f733a3ec2b8e79d@kernel.crashing.org \
    --to=segher@kernel.crashing.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-sparse@vger.kernel.org \
    --cc=torvalds@linux-foundation.org \
    --cc=viro@ftp.linux.org.uk \
    /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).