Re: [PATCH 13/14] iopoll: avoid -Wint-in-bool-context warning
From: Arnd Bergmann
Date: Fri Jul 14 2017 - 06:22:07 EST
On Fri, Jul 14, 2017 at 11:55 AM, Joe Perches <joe@xxxxxxxxxxx> wrote:
> On Fri, 2017-07-14 at 11:31 +0200, Arnd Bergmann wrote:
>> When we pass the result of a multiplication as the timeout, we
>> can get a warning:
>>
>> drivers/mmc/host/bcm2835.c:596:149: error: '*' in boolean context, suggest '&&' instead [-Werror=int-in-bool-context]
>> drivers/mfd/arizona-core.c:247:195: error: '*' in boolean context, suggest '&&' instead [-Werror=int-in-bool-context]
>>
>> This is easy to avoid by comparing the timeout to zero instead,
>> making it a boolean expression.
>
> Perhaps this is better as != 0 if the multiply is signed.
I thought about that, but decided that as a negative timeout_us already
gives us rather random behavior (ktime_add_us() takes an unsigned
argument), the '>' comparison gives a more well-defined result by
ignoring the timeout.
Arnd