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Sender: Guenter Roeck <groeck7@gmail.com>
Subject: Re: [PATCH] Revert "Enable '-Werror' by default for all kernel
 builds"
To:     Pavel Machek <pavel@ucw.cz>, Randy Dunlap <rdunlap@infradead.org>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
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From:   Guenter Roeck <linux@roeck-us.net>
Message-ID: <62c6b091-12ad-a1f0-637c-f696c7dae325@roeck-us.net>
Date:   Mon, 13 Sep 2021 07:33:31 -0700
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On 9/13/21 2:32 AM, Pavel Machek wrote:
> Hi!
> 
>>>>   config WERROR
>>>>          bool "Compile the kernel with warnings as errors"
>>>> -       default y
>>>> +       default COMPILE_TEST
>>>
>>> That seems reasonable. It very much is about build-testing.
>>
>> That and 2 more things IMO:
>>
>> a. having developers be responsible for build warnings, not just
>>     build errors
>>
>> b. having maintainers merge them more like they are build errors
>>     and not just some warnings that can be overlooked.
>>
>> I don't see enough of a. or b.  :(
> 
> Do we really want developers treat warnings as errors? When the code
> is okay but some random version of gcc dislikes it...
> 
> Plus, there's question of stable. We already get ton of churn there
> ("this fixes random warning"). WERROR will only encourage that...
> 

All Chrome OS builds are already done with -Werror enabled. Having it
enabled in the incoming stable releases will reduce our workload when
backporting stable releases. I am actually working on making at
least chromeos-5.10 "clean" for allmodconfig builds on arm, arm64,
and x86 (everything else is hopeless, and even arm may be futile,
but arm64 and x86 seem to be doable).

I'd rather have warnings fixed in incoming stable releases than having
to pull additional patches into our kernels.

Guenter