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Message-ID: <81585705-6ed8-12e5-1355-332a6a5d2b17@infradead.org>
Date:   Fri, 8 Apr 2022 13:36:02 -0700
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Subject: Re: [PATCHv1] kbuild: support W=e to make build abort in case of
 warning
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To:     Nick Desaulniers <ndesaulniers@google.com>,
        Masahiro Yamada <masahiroy@kernel.org>
Cc:     Yann Droneaud <ydroneaud@opteya.com>,
        Michal Marek <michal.lkml@markovi.net>,
        Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>
References: <1422803720-14723-1-git-send-email-ydroneaud@opteya.com>
 <20220408084607.106468-1-ydroneaud@opteya.com>
 <CAK7LNAQZLt_OecOogOQiSu5snW+sffsMoFgVcjPTx_idj_=_tQ@mail.gmail.com>
 <CAKwvOd=yNnKsHJo0QWvoTuFF9p-y=cTftTD+7FY-wJ_f23zFTQ@mail.gmail.com>
From:   Randy Dunlap <rdunlap@infradead.org>
In-Reply-To: <CAKwvOd=yNnKsHJo0QWvoTuFF9p-y=cTftTD+7FY-wJ_f23zFTQ@mail.gmail.com>
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On 4/8/22 13:29, Nick Desaulniers wrote:
> On Fri, Apr 8, 2022 at 4:06 AM Masahiro Yamada <masahiroy@kernel.org> wrote:
>>
>> On Fri, Apr 8, 2022 at 5:46 PM Yann Droneaud <ydroneaud@opteya.com> wrote:
>>>
>>> When developing new code/feature, CONFIG_WERROR is most
>>> often turned off, especially for people using make W=12 to
>>> get more warnings.
>>>
>>> In such case, turning on -Werror temporarily would require
>>> switching on CONFIG_WERROR in the configuration, building,
>>> then switching off CONFIG_WERROR.
>>>
>>> For this use case, this patch introduces a new 'e' modifier
>>> to W= as a short hand for KCFLAGS+=-Werror" so that -Werror
>>> got added to the kernel (built-in) and modules' CFLAGS.
>>>
>>> Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
>>> ---
>>>  Makefile                   |  1 +
>>>  scripts/Makefile.extrawarn | 13 +++++++++++--
>>>  2 files changed, 12 insertions(+), 2 deletions(-)
>>>
>>> Changes since v0[0]:
>>>
>>>  - rebase on top of commit 64a91907c896 ("kbuild: refactor scripts/Makefile.extrawarn")
>>>  - document use case after commit 3fe617ccafd6 ("Enable '-Werror' by default for all kernel builds")
>>>
>>> [0] https://lore.kernel.org/all/1422803720-14723-1-git-send-email-ydroneaud@opteya.com/
>>
>>
>> I remembered the previous submission, I liked it, but I had lost it.
>>
>> It seems already 7 years ago, (before I became the Kbuild maintainer).
>> Thanks for coming back to this.
>>
>>
>> I like this, but I will wait some time for review comments.
> 
> Dunno, this seems pretty simple:
> 
> $ ./scripts/config -e WERROR
> $ make ... W=12

Yeah, that's about what I was thinking too..

-- 
~Randy