Message-ID: <1479383715.19539.53.camel@tiscali.nl>
Subject: Re: i2c: undefined option I2C_ALGO_BUSCLEAR
From: Paul Bolle <pebolle@tiscali.nl>
To: Valentin Rothberg <valentinrothberg@gmail.com>
Cc: smohammed@nvidia.com, treding@nvidia.com,
        Michal Marek <mmarek@suse.cz>, linux-kernel@vger.kernel.org
Date: Thu, 17 Nov 2016 12:55:15 +0100
In-Reply-To: <20161117113301.qqce6a4kmmsv6ijl@tumbleweed>
References: <CAD3Xx4+ieNPqsumoXuiTtpwxct-66ipJB8tb-Kfpe1njBc+OZQ@mail.gmail.com>
         <1479373111.19539.24.camel@tiscali.nl>
         <20161117113301.qqce6a4kmmsv6ijl@tumbleweed>
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Hi Valentin,

On Thu, 2016-11-17 at 12:33 +0100, Valentin Rothberg wrote:
> I tested your patch and it works properly for me.  It even still applies
> on linux-next.

Cool.

(We should probably compile a list of current invalid selects somewhere
publicly, and team up to submit patches for the low hanging fruit (ie, obvious
typos) and for the arches that actually matter before I resubmit.)

> Would it be possible to extend your patch to also check
> symbols in other statements (depends on, if, etc.)?

No. Depending on an unknown symbol is common and correct. Think
    depends on SOME_OBSCURE_ARM_BOARD

somewhere in drivers. Only arm builds will ever know about the
SOME_OBSCURE_ARM_BOARD symbol.

What could be done is starting any "make *config" target with a treewide pass
over all Kconfig files to collect all valid symbols and so spot typos and
other obviously incorrect. The example that comes to mind is
    depends on SH

that I have spotted a few times in the past years. But this treewide pass will
incur some runtime cost and might not be easy to implement cleanly. Perhaps
we're better of with using your script for that.

Thanks,


Paul Bolle