Re: [Qemu-devel] Headers without multiple inclusion guards

From: Greg Kurz <groug@kaod.org>
To: Markus Armbruster <armbru@redhat.com>
Cc: "Peter Maydell" <peter.maydell@linaro.org>,
	"Chris Wulff" <crwulff@gmail.com>,
	"Sagar Karandikar" <sagark@eecs.berkeley.edu>,
	"David Hildenbrand" <david@redhat.com>,
	"James Hogan" <jhogan@kernel.org>,
	"Anthony Green" <green@moxielogic.com>,
	"Palmer Dabbelt" <palmer@sifive.com>,
	"Mark Cave-Ayland" <mark.cave-ayland@ilande.co.uk>,
	qemu-devel@nongnu.org, "Max Filippov" <jcmvbkbc@gmail.com>,
	"Dmitry Fleytman" <dmitry.fleytman@gmail.com>,
	"Alistair Francis" <Alistair.Francis@wdc.com>,
	"Gerd Hoffmann" <kraxel@redhat.com>,
	"Edgar E. Iglesias" <edgar.iglesias@gmail.com>,
	"Guan Xuetao" <gxt@mprc.pku.edu.cn>,
	"Marek Vasut" <marex@denx.de>,
	"Stefano Stabellini" <sstabellini@kernel.org>,
	"Aleksandar Rikalo" <arikalo@wavecomp.com>,
	"Helge Deller" <deller@gmx.de>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	"Laszlo Ersek" <lersek@redhat.com>,
	"Halil Pasic" <pasic@linux.ibm.com>,
	"Christian Borntraeger" <borntraeger@de.ibm.com>,
	"Anthony Perard" <anthony.perard@citrix.com>,
	"Richard Henderson" <rth@twiddle.net>,
	"Jason Wang" <jasowang@redhat.com>,
	"Artyom Tarasenko" <atar4qemu@gmail.com>,
	"Laurent Vivier" <lvivier@redhat.com>,
	"Thomas Huth" <thuth@redhat.com>,
	"Riku Voipio" <riku.voipio@iki.fi>,
	"Eduardo Habkost" <ehabkost@redhat.com>,
	"Alistair Francis" <alistair@alistair23.me>,
	"Marcelo Tosatti" <mtosatti@redhat.com>,
	"Beniamino Galvani" <b.galvani@gmail.com>,
	"Eric Auger" <eric.auger@redhat.com>,
	"Paul Durrant" <paul.durrant@citrix.com>,
	"Stafford Horne" <shorne@gmail.com>,
	"Alex Bennée" <alex.bennee@linaro.org>,
	"David Gibson" <david@gibson.dropbear.id.au>,
	"Daniel P. Berrange" <berrange@redhat.com>,
	"Claudio Fontana" <claudio.fontana@gmail.com>,
	"Bastian Koppelmann" <kbastian@mail.uni-paderborn.de>,
	"Cornelia Huck" <cohuck@redhat.com>,
	"Claudio Fontana" <claudio.fontana@huawei.com>,
	"Laurent Vivier" <laurent@vivier.eu>,
	"Andrew Baumann" <Andrew.Baumann@microsoft.com>,
	"Philippe Mathieu-Daudé" <philmd@redhat.com>,
	"Michael Walle" <michael@walle.cc>,
	"Aleksandar Markovic" <amarkovic@wavecomp.com>,
	"Paolo Bonzini" <pbonzini@redhat.com>,
	"Aurelien Jarno" <aurelien@aurel32.net>,
	"Philippe Mathieu-Daudé" <f4bug@amsat.org>
Subject: Re: [Qemu-devel] Headers without multiple inclusion guards
Date: Wed, 29 May 2019 11:19:20 +0200	[thread overview]
Message-ID: <20190529111920.66dd27cd@bahia.lab.toulouse-stg.fr.ibm.com> (raw)
In-Reply-To: <87lfyqla7r.fsf@dusky.pond.sub.org>

On Tue, 28 May 2019 20:12:24 +0200
Markus Armbruster <armbru@redhat.com> wrote:

> We have a bunch of headers without multiple inclusion guards.  Some are
> clearly intentional, some look accidental.  Too many for me to find out
> by examining each of them, so I'm asking their maintainers.
> 
> Why do I ask?  I'd like to mark the intentional ones and fix the
> accidental ones, so they don't flunk "make check-headers" from "[RFC v4
> 0/7] Baby steps towards saner headers" just because they lack multiple
> inclusion guards.
> 
> Just in case: what's a multiple inclusion guard?  It's
> 
>     #ifndef UNIQUE_GUARD_SYMBOL_H
>     #define UNIQUE_GUARD_SYMBOL_H
>     ...
>     #endif
> 
> with nothing but comments outside the conditional, so that the header
> can safely be included more than once.
> 
> I append the alphabetical list of headers without multiple inclusion
> guards (as reported by scripts/clean-header-guards -nv), followed by the
> same list sorted into maintainer buckets.  If you're cc'ed, please find
> your bucket(s), and tell me which headers intentionally lack guards.
> 
[...]
> virtio-9p
> M: Greg Kurz <groug@kaod.org>
> hw/9pfs/xen-9pfs.h
> 

It doesn't seem to be intentional, but probably better to
ask Stefano Stabellini, Paul Durrant or Anthony Perard
since this is a xen-9p header, not virtio-9p.

In the meantime, I'll send a fix for MAINTAINERS.

Cheers,

--
Greg