Re: [PATCH] platform/x86: thinkpad_acpi: Fix bitwise vs. logical warning
From: Nick Desaulniers
Date: Mon Oct 18 2021 - 14:34:49 EST
On Mon, Oct 18, 2021 at 11:26 AM Nathan Chancellor <nathan@xxxxxxxxxx> wrote:
>
> A new warning in clang points out a use of bitwise OR with boolean
> expressions in this driver:
>
> drivers/platform/x86/thinkpad_acpi.c:9061:11: error: use of bitwise '|' with boolean operands [-Werror,-Wbitwise-instead-of-logical]
> else if ((strlencmp(cmd, "level disengaged") == 0) |
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> ||
> drivers/platform/x86/thinkpad_acpi.c:9061:11: note: cast one or both operands to int to silence this warning
> 1 error generated.
>
> This should clearly be a logical OR so change it to fix the warning.
>
> Fixes: fe98a52ce754 ("ACPI: thinkpad-acpi: add sysfs support to fan subdriver")
> Link: https://github.com/ClangBuiltLinux/linux/issues/1476
> Reported-by: Tor Vic <torvic9@xxxxxxxxxxx>
> Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>
LGTM, thanks for the patch! I guess this would be the first
"interesting" case this warning has found in kernel sources?
Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
> ---
> drivers/platform/x86/thinkpad_acpi.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
> index 07b9710d500e..7442c3bb446a 100644
> --- a/drivers/platform/x86/thinkpad_acpi.c
> +++ b/drivers/platform/x86/thinkpad_acpi.c
> @@ -9058,7 +9058,7 @@ static int fan_write_cmd_level(const char *cmd, int *rc)
>
> if (strlencmp(cmd, "level auto") == 0)
> level = TP_EC_FAN_AUTO;
> - else if ((strlencmp(cmd, "level disengaged") == 0) |
> + else if ((strlencmp(cmd, "level disengaged") == 0) ||
> (strlencmp(cmd, "level full-speed") == 0))
> level = TP_EC_FAN_FULLSPEED;
> else if (sscanf(cmd, "level %d", &level) != 1)
>
> base-commit: 85303db36b6e170917a7bc6aae4898c31a5272a0
> --
> 2.33.1.637.gf443b226ca
>
--
Thanks,
~Nick Desaulniers