From: Andrey Ryabinin <aryabinin@virtuozzo.com>
To: kbuild test robot <fengguang.wu@intel.com>
Cc: kbuild-all@01.org, Andrew Morton <akpm@linux-foundation.org>,
Linux Memory Management List <linux-mm@kvack.org>
Subject: Re: [linux-next:master 5266/5426] arch/x86/kernel/cpu/mcheck/mce.c:884:5: warning: 'order' may be used uninitialized in this function
Date: Thu, 10 Dec 2015 19:02:13 +0300 [thread overview]
Message-ID: <5669A205.7080205@virtuozzo.com> (raw)
In-Reply-To: <201512102333.nZemw8i3%fengguang.wu@intel.com>
On 12/10/2015 06:05 PM, kbuild test robot wrote:
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
> head: 8225f4e85cb03daea14661380745886ce01fd83a
> commit: 0dd08f12cafd7868be55bc10ebcd4ea13880860b [5266/5426] UBSAN: run-time undefined behavior sanity checker
> config: x86_64-randconfig-s5-12102221 (attached as .config)
> reproduce:
> git checkout 0dd08f12cafd7868be55bc10ebcd4ea13880860b
> # save the attached .config to linux build tree
> make ARCH=x86_64
>
> Note: it may well be a FALSE warning. FWIW you are at least aware of it now.
> http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings
>
This is certainly a false positive.
It seems that UBSAN could make gcc more stupid and increase number of maybe-uninitialized false-positives.
> All warnings (new ones prefixed by >>):
>
> arch/x86/kernel/cpu/mcheck/mce.c: In function 'do_machine_check':
>>> arch/x86/kernel/cpu/mcheck/mce.c:884:5: warning: 'order' may be used uninitialized in this function [-Wmaybe-uninitialized]
> if (order == 1) {
> ^
> arch/x86/kernel/cpu/mcheck/mce.c:984:6: note: 'order' was declared here
> int order;
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
prev parent reply other threads:[~2015-12-10 16:01 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-12-10 15:05 [linux-next:master 5266/5426] arch/x86/kernel/cpu/mcheck/mce.c:884:5: warning: 'order' may be used uninitialized in this function kbuild test robot
2015-12-10 16:02 ` Andrey Ryabinin [this message]
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=5669A205.7080205@virtuozzo.com \
--to=aryabinin@virtuozzo.com \
--cc=akpm@linux-foundation.org \
--cc=fengguang.wu@intel.com \
--cc=kbuild-all@01.org \
--cc=linux-mm@kvack.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;
as well as URLs for NNTP newsgroup(s).