Re: [PATCH 10/10] media: omap3isp: avoid warnings at IS_OUT_OF_BOUNDS()

From: Laurent Pinchart
Date: Mon Nov 22 2021 - 05:05:21 EST


Hi Mauro,

Thank you for the patch.

On Mon, Nov 22, 2021 at 09:26:12AM +0000, Mauro Carvalho Chehab wrote:
> Clang with W=1 produces the following warnings:
>
> drivers/media/platform/omap3isp/isph3a_af.c:173:6: error: result of comparison of constant 256 with expression of type '__u8' (aka 'unsigned char') is always false [-Werror,-Wtautological-constant-out-of-range-compare]
> if (IS_OUT_OF_BOUNDS(paxel_cfg->height, OMAP3ISP_AF_PAXEL_HEIGHT_MIN,
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/media/platform/omap3isp/isph3a_af.c:24:33: note: expanded from macro 'IS_OUT_OF_BOUNDS'
> (((value) < (min)) || ((value) > (max)))
> ~~~~~~~ ^ ~~~~~
> drivers/media/platform/omap3isp/isph3a_af.c:179:6: error: result of comparison of constant 256 with expression of type '__u8' (aka 'unsigned char') is always false [-Werror,-Wtautological-constant-out-of-range-compare]
> if (IS_OUT_OF_BOUNDS(paxel_cfg->width, OMAP3ISP_AF_PAXEL_WIDTH_MIN,
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/media/platform/omap3isp/isph3a_af.c:24:33: note: expanded from macro 'IS_OUT_OF_BOUNDS'
> (((value) < (min)) || ((value) > (max)))
> ~~~~~~~ ^ ~~~~~
> 2 errors generated.
>
> Use a typecast to avoid such warnings.
>
> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
> ---
>
> To avoid mailbombing on a large number of people, only mailing lists were C/C on the cover.
> See [PATCH 00/10] at: https://lore.kernel.org/all/cover.1637573097.git.mchehab+huawei@xxxxxxxxxx/
>
> drivers/media/platform/omap3isp/isph3a_af.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/media/platform/omap3isp/isph3a_af.c b/drivers/media/platform/omap3isp/isph3a_af.c
> index a65cfdfa9637..de7b116d0122 100644
> --- a/drivers/media/platform/omap3isp/isph3a_af.c
> +++ b/drivers/media/platform/omap3isp/isph3a_af.c
> @@ -21,7 +21,7 @@
> #include "ispstat.h"
>
> #define IS_OUT_OF_BOUNDS(value, min, max) \
> - (((value) < (min)) || ((value) > (max)))
> + ((((unsigned int)value) < (min)) || (((unsigned int)value) > (max)))

It could have been a good occasion to replace the macro with an inline
function.

Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>

>
> static void h3a_af_setup_regs(struct ispstat *af, void *priv)
> {

--
Regards,

Laurent Pinchart