RE: [PATCH] [media] rcar_drif: fix potential uninitialized variable use

From: Ramesh Shanmugasundaram
Date: Fri Sep 15 2017 - 04:23:39 EST


Hi Arnd,

Thank you for the patch.

> Subject: [PATCH] [media] rcar_drif: fix potential uninitialized variable
> use
>
> Older compilers like gcc-4.6 may run into a case that returns an
> uninitialized variable from rcar_drif_enable_rx() if that function was
> ever called with an empty cur_ch_mask:
>
> drivers/media/platform/rcar_drif.c:658:2: error: âretâ may be used
> uninitialized in this function [-Werror=uninitialized]
>
> Newer compilers don't have that problem as they optimize the 'ret'
> variable away and just return zero in that case.
>
> This changes the function to return -EINVAL for this particular failure,
> to make it consistent across all compiler versions.
> In case gcc gets changed to report a warning for it in the future, it's
> also a good idea to shut it up now.
>
> Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82203
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Acked-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@xxxxxxxxxxxxxx>

Thanks,
Ramesh