From: Arnd Bergmann <arnd@arndb.de>
To: James Bottomley <jejb@linux.vnet.ibm.com>
Cc: qla2xxx-upstream@qlogic.com,
"Martin K. Petersen" <martin.petersen@oracle.com>,
Nicholas Bellinger <nab@linux-iscsi.org>,
Himanshu Madhani <himanshu.madhani@qlogic.com>,
Quinn Tran <quinn.tran@qlogic.com>,
Alexei Potashnik <alexei@purestorage.com>,
Bart Van Assche <bart.vanassche@sandisk.com>,
Swapnil Nagle <swapnil.nagle@purestorage.com>,
linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] qla2xxx: avoid maybe_uninitialized warning
Date: Wed, 16 Mar 2016 13:59:49 +0100 [thread overview]
Message-ID: <2808565.5VeioJTJAb@wuerfel> (raw)
In-Reply-To: <1458078554.2375.97.camel@linux.vnet.ibm.com>
On Tuesday 15 March 2016 14:49:14 James Bottomley wrote:
> On Tue, 2016-03-15 at 22:40 +0100, Arnd Bergmann wrote:
> >
> > This slightly rearranges the code to move the second if() block
> > into the first one, to avoid the warning while retaining the
> > behavior of the code.
>
> I thought our usual policy was to ask someone to fix the compiler when
> it emitted a spurious warning.
No, the rule is that we shouldn't blindly add initializations to
the variables when the compiler should have figured it out.
In this case, I wouldn't expect the compiler to ever see through
the unlikely() macro, and I'm not adding a potentially counterproductive
initialization, so I see no reason not to apply the patch.
Making it easier for the compiler to figure out what is going
on should also lead to slightly better object code. If you think
my patch makes it less readable, an alternative would be to remove
the 'unlikely', which also gets rid of the warning.
Arnd
next prev parent reply other threads:[~2016-03-16 13:05 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-03-15 21:40 [PATCH] qla2xxx: avoid maybe_uninitialized warning Arnd Bergmann
2016-03-15 21:49 ` James Bottomley
2016-03-16 12:59 ` Arnd Bergmann [this message]
2016-03-16 14:05 ` Himanshu Madhani
2016-03-16 14:24 ` James Bottomley
2016-03-16 15:03 ` Tomas Henzl
2016-03-16 15:11 ` Tomas Henzl
2016-03-16 15:47 ` Ewan D. Milne
2016-03-18 19:26 ` Martin K. Petersen
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=2808565.5VeioJTJAb@wuerfel \
--to=arnd@arndb.de \
--cc=alexei@purestorage.com \
--cc=bart.vanassche@sandisk.com \
--cc=himanshu.madhani@qlogic.com \
--cc=jejb@linux.vnet.ibm.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-scsi@vger.kernel.org \
--cc=martin.petersen@oracle.com \
--cc=nab@linux-iscsi.org \
--cc=qla2xxx-upstream@qlogic.com \
--cc=quinn.tran@qlogic.com \
--cc=swapnil.nagle@purestorage.com \
/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