Re: [PATCH] decompressor: provide missing prototypes

From: Arnd Bergmann
Date: Thu May 18 2023 - 09:24:10 EST


On Wed, May 17, 2023, at 22:49, Andrew Morton wrote:
> On Wed, 17 May 2023 15:19:31 +0200 Arnd Bergmann <arnd@xxxxxxxxxx> wrote:
>
>> From: Arnd Bergmann <arnd@xxxxxxxx>
>>
>> The entry points for the decompressor don't always have a prototype
>> included in the .c file:
>>
>> lib/decompress_inflate.c:42:17: error: no previous prototype for '__gunzip' [-Werror=missing-prototypes]
>> lib/decompress_unxz.c:251:17: error: no previous prototype for 'unxz' [-Werror=missing-prototypes]
>> lib/decompress_unzstd.c:331:17: error: no previous prototype for 'unzstd' [-Werror=missing-prototypes]
>>
>> include the correct headers for unxz and unzstd, and mark the
>> inflate function above as unconditionally 'static' to avoid
>> these warnings.
>
> These are errors, not warnings?
>
> Under what circumstances do they occur?

Running "make W=1" turns these errors on as warnings, enabling
CONFIG_WERROR turns all warnings into errors.

> Shouldn't we cc:stable? If so, do we have a suitable Fixes: target?

I have sent 140 patches for these, there is probably no point in backporting
them all. My hope is that we can enable -Wmissing-prototypes by default
after these are all merged, but that patch would not get backported
either.

I meant to include a link with the explanations to

https://people.kernel.org/arnd/missing-prototype-warnings-in-the-kernel

in my series but didn't have that in the separate patches.

Arnd