Message-ID: <2d790206-124b-f850-895f-a57a74c55f79@gmail.com>
Date:   Fri, 19 Nov 2021 17:22:48 +0100
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Subject: Re: [PATCH 00/17] Add memberof(), split some headers, and slightly
 simplify code
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To:     Arnd Bergmann <arnd@arndb.de>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        Ajit Khaparde <ajit.khaparde@broadcom.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Borislav Petkov <bp@suse.de>,
        Corey Minyard <cminyard@mvista.com>, Chris Mason <clm@fb.com>,
        Christian Brauner <christian.brauner@ubuntu.com>,
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        Jani Nikula <jani.nikula@linux.intel.com>,
        Jason Wang <jasowang@redhat.com>,
        Jitendra Bhivare <jitendra.bhivare@broadcom.com>,
        John Hubbard <jhubbard@nvidia.com>,
        "John S . Gruber" <JohnSGruber@gmail.com>,
        Jonathan Cameron <Jonathan.Cameron@huawei.com>,
        Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
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        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
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References: <20211119113644.1600-1-alx.manpages@gmail.com>
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From:   "Alejandro Colomar (man-pages)" <alx.manpages@gmail.com>
In-Reply-To: <CAK8P3a06CMzWVj2C3P5v0u8ZVPumXJKrq=TdjSq1NugmeT7-RQ@mail.gmail.com>
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On 11/19/21 17:18, Arnd Bergmann wrote:
> On Fri, Nov 19, 2021 at 5:10 PM Andy Shevchenko
> <andriy.shevchenko@linux.intel.com> wrote:
>> On Fri, Nov 19, 2021 at 04:57:46PM +0100, Arnd Bergmann wrote:
> 
>>> The main problem with this approach is that as soon as you start
>>> actually reducing the unneeded indirect includes, you end up with
>>> countless .c files that no longer build because they are missing a
>>> direct include for something that was always included somewhere
>>> deep underneath, so I needed a second set of scripts to add
>>> direct includes to every .c file.
>>
>> Can't it be done with cocci support?
> 
> There are many ways of doing it, but they all tend to suffer from the
> problem of identifying which headers are actually needed based on
> the contents of a file, and also figuring out where to put the extra
> #include if there are complex #ifdefs.
> 
> For reference, see below for the naive pattern matching I tried.
> This is obviously incomplete and partially wrong.

FYI, if you may not know the tool,
theres include-what-you-use(1) (a.k.a. iwyu(1))[1],
although it is still not mature,
and I'm helping improve it a bit.

If I understood better the kernel Makefiles,
I'd try it.

You can try it yourselves.
I still can't use it for my own code,
since it has a lot of false positives.

Cheers,
Alex

[1]: <https://include-what-you-use.org/>


-- 
Alejandro Colomar
Linux man-pages comaintainer; https://www.kernel.org/doc/man-pages/
http://www.alejandro-colomar.es/