public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Dan Carpenter <dan.carpenter@oracle.com>
To: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Markus Elfring <Markus.Elfring@web.de>,
	kernel-janitors@vger.kernel.org,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Joe Perches <joe@perches.com>, Kees Cook <keescook@chromium.org>,
	Nick Desaulniers <ndesaulniers@google.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] string.h: Mark 34 functions with __must_check
Date: Wed, 9 Oct 2019 17:30:01 +0300	[thread overview]
Message-ID: <20191009143000.GD13286@kadam> (raw)
In-Reply-To: <b1f055ec-b4ec-d0ed-a03d-7d9828fa9440@rasmusvillemoes.dk>

On Wed, Oct 09, 2019 at 04:21:20PM +0200, Rasmus Villemoes wrote:
> On 09/10/2019 15.56, Dan Carpenter wrote:
> > That's because glibc strlen is annotated with __attribute_pure__ which
> > means it has no side effects.
> 
> I know, except it has nothing to do with glibc headers. Just try the
> same thing in the kernel. gcc itself knows this about __builtin_strlen()
> etc. If anything, we could annotate some of our non-standard functions
> (say, memchr_inv) with __pure - then we'd both get the Wunused-value in
> the nonsense cases, and allow gcc to optimize or reorder the calls.

Huh.  You're right.  GCC already knows.  So this patch is pointless like
you say.

regards,
dan carpenter


  reply	other threads:[~2019-10-09 14:30 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-09 12:14 [PATCH] string.h: Mark 34 functions with __must_check Markus Elfring
2019-10-09 13:26 ` Rasmus Villemoes
2019-10-09 13:56   ` Dan Carpenter
2019-10-09 14:21     ` Rasmus Villemoes
2019-10-09 14:30       ` Dan Carpenter [this message]
2019-10-09 16:31         ` Nick Desaulniers
2019-10-09 18:45           ` Dan Carpenter
2019-10-10  7:20           ` Rasmus Villemoes
2019-10-09 16:37   ` Nick Desaulniers
2019-10-09 16:42   ` Markus Elfring
2019-10-11  5:15   ` Searching for missing variable checks Markus Elfring
2019-10-09 15:09 ` [PATCH] string.h: Mark 34 functions with __must_check Steven Rostedt
2019-10-09 16:13   ` Nick Desaulniers
2019-10-09 16:27     ` Steven Rostedt
2019-10-09 16:40       ` Nick Desaulniers
2019-10-09 17:04         ` Markus Elfring
2019-10-09 17:33           ` Nick Desaulniers
2019-10-09 18:06             ` Markus Elfring
2019-10-09 16:38     ` [PATCH] " Joe Perches
2019-10-09 17:33       ` Nick Desaulniers
2019-10-10 14:27         ` David Sterba
2019-10-10 14:34           ` Joe Perches
2019-10-11  5:00             ` Markus Elfring
2019-10-10 15:46           ` [PATCH] " David Laight
2019-10-09 20:06   ` Markus Elfring
2019-10-10  5:29     ` Andy Shevchenko
2019-10-10  7:25       ` Markus Elfring
2019-12-21  9:30 ` Markus Elfring

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=20191009143000.GD13286@kadam \
    --to=dan.carpenter@oracle.com \
    --cc=Markus.Elfring@web.de \
    --cc=akpm@linux-foundation.org \
    --cc=alexander.shishkin@linux.intel.com \
    --cc=andriy.shevchenko@linux.intel.com \
    --cc=joe@perches.com \
    --cc=keescook@chromium.org \
    --cc=kernel-janitors@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux@rasmusvillemoes.dk \
    --cc=ndesaulniers@google.com \
    --cc=rostedt@goodmis.org \
    /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