Re: [PATCH] [RESEND] floppy: fix harmless clang build warning

[Jens Axboe]

On 6/19/19 7:19 AM, Arnd Bergmann wrote:
> clang warns about unusual code in floppy.c that looks like it
> was intended to be a bit mask operation, checking for a specific
> bit in the UDP->cmos variable (FLOPPY1_TYPE expands to '4' on
> ARM):
> 
> drivers/block/floppy.c:3902:17: error: use of logical '&&' with constant operand [-Werror,-Wconstant-logical-operand]
>          if (!UDP->cmos && FLOPPY1_TYPE)
>                         ^  ~~~~~~~~~~~~
> drivers/block/floppy.c:3902:17: note: use '&' for a bitwise operation
>          if (!UDP->cmos && FLOPPY1_TYPE)
> 
> The check here is redundant anyway, if FLOPPY1_TYPE is zero, then
> assigning it to a zero UDP->cmos field does not change anything,
> so removing the extra check here has no effect other than shutting
> up the warning.
> 
> On x86, this will no longer read a hardware register, as the
> FLOPPY1_TYPE macro is not expanded if UDP->cmos is already
> zero, but the result is the same.

Applied, thanks.

-- 
Jens Axboe