[PATCH] powerpc/futex: fix warning: 'oldval' may be used uninitialized in this function

Michael Ellerman patch-notifications at ellerman.id.au
Thu Aug 22 23:09:00 AEST 2019


On Wed, 2019-08-14 at 09:25:52 UTC, Christophe Leroy wrote:
> CC      kernel/futex.o
> kernel/futex.c: In function 'do_futex':
> kernel/futex.c:1676:17: warning: 'oldval' may be used uninitialized in this function [-Wmaybe-uninitialized]
>    return oldval == cmparg;
>                  ^
> kernel/futex.c:1651:6: note: 'oldval' was declared here
>   int oldval, ret;
>       ^
> 
> This is because arch_futex_atomic_op_inuser() only sets *oval
> if ret is NUL and GCC doesn't see that it will use it only when
> ret is NUL.
> 
> Anyway, the non-NUL ret path is an error path that won't suffer from
> setting *oval, and as *oval is a local var in futex_atomic_op_inuser()
> it will have no impact.
> 
> Signed-off-by: Christophe Leroy <christophe.leroy at c-s.fr>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/38a0d0cdb46d3f91534e5b9839ec2d67be14c59d

cheers


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