Re: [tip:core/urgent] futex: Address compiler warnings in exit_robust_list

["Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>]

Hallo Thomas,

On Wed, Nov 10, 2010 at 12:30:44PM +0000, tip-bot for Darren Hart wrote:
> Commit-ID:  4c115e951d80aff126468adaec7a6c7854f61ab8
> Gitweb:     http://git.kernel.org/tip/4c115e951d80aff126468adaec7a6c7854f61ab8
> Author:     Darren Hart <dvhart@linux.intel.com>
> AuthorDate: Thu, 4 Nov 2010 15:00:00 -0400
> Committer:  Thomas Gleixner <tglx@linutronix.de>
> CommitDate: Wed, 10 Nov 2010 13:27:50 +0100
> 
> futex: Address compiler warnings in exit_robust_list
> 
> Since commit 1dcc41bb (futex: Change 3rd arg of fetch_robust_entry()
> to unsigned int*) some gcc versions decided to emit the following
> warning:
> 
> kernel/futex.c: In function ‘exit_robust_list’:
> kernel/futex.c:2492: warning: ‘next_pi’ may be used uninitialized in this function
> 
> The commit did not introduce the warning as gcc should have warned
> before that commit as well. It's just gcc being silly.
> 
> The code path really can't result in next_pi being unitialized (or
> should not), but let's keep the build clean. Annotate next_pi as an
> uninitialized_var.
> 
> [ tglx: Addressed the same issue in futex_compat.c and massaged the
>   	changelog ]
> 
> Signed-off-by: Darren Hart <dvhart@linux.intel.com>
> Tested-by: Matt Fleming <matt@console-pimps.org>
> Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
I don't care much (at least until someone claims this change to
introduce a regression), but I didn't test it.  I only suggested to use 
uninitialized_var instead of = 0.

Thanks
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |