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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Joe Perches' <joe@perches.com>,
        'Andrew Morton' <akpm@linux-foundation.org>,
        Andy Whitcroft <apw@canonical.com>,
        LKML <linux-kernel@vger.kernel.org>
Subject: RE: [RFC PATCH] checkpatch: check for function calls with struct or
 union on stack
Thread-Topic: [RFC PATCH] checkpatch: check for function calls with struct or
 union on stack
Thread-Index: AQHUJRcFUx4+BuOgSky66zuZVVqB+6Si1nhw///yOQCAABM5YA==
Date:   Fri, 27 Jul 2018 10:21:37 +0000
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From: Joe Perches
> Sent: 27 July 2018 11:09
> On Fri, 2018-07-27 at 10:04 +0000, David Laight wrote:
> > From: Andrew Morton
> > > Sent: 26 July 2018 20:28
> > > On Thu, 26 Jul 2018 12:25:33 -0700 Andrew Morton <akpm@linux-foundation.org> wrote:
> > >
> > > > I'll give it a spin, see how noisy it is.
> > >
> > > Actually, I would prefer if the message, changelog and title
> > > used the term "passed by value".  It's a more familiar term
> > > and it is possible for a passed-by-value aggregate to in fact
> > > be passed in registers.
> >
> > You need to detect (and ignore) 'small' structures.
> 
> checkpatch is stupid and basically can't do that
> as it has no context other than the current line.
> 
> It would need a list of specific struct types to
> ignore.  Care to create and send that list to me?

Does it even have the type?
If it has the prototype it could ignore aggregates that
are marked 'const'.

At least we're not in the K&R days where missing out the
& got very confusing.

	David

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