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Subject: Re: [Qemu-devel] [PATCH v3 1/8] CODING_STYLE: Section about
 conditional statement
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To: Alex =?iso-8859-1?Q?Benn=E9e?= <alex.bennee@linaro.org>
Cc: "peter.maydell@linaro.org" <peter.maydell@linaro.org>, "peter.crosthwaite@xilinx.com" <peter.crosthwaite@xilinx.com>, "Huangweidong (C)" <weidong.huang@huawei.com>, "aliguori@amazon.com" <aliguori@amazon.com>, "marcel.a@redhat.com" <marcel.a@redhat.com>, Luonengjun <luonengjun@huawei.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, "armbru@redhat.com" <armbru@redhat.com>, "Gonglei (Arei)" <arei.gonglei@huawei.com>, "av1474@comtv.ru" <av1474@comtv.ru>, "kraxel@redhat.com" <kraxel@redhat.com>, "stefanha@redhat.com" <stefanha@redhat.com>, "pbonzini@redhat.com" <pbonzini@redhat.com>, "dmitry@daynix.com" <dmitry@daynix.com>, "imammedo@redhat.com" <imammedo@redhat.com>, "Huangpeng (Peter)" <peter.huangpeng@huawei.com>, "lcapitulino@redhat.com" <lcapitulino@redhat.com>, "afaerber@suse.de" <afaerber@suse.de>, "dgilbert@redhat.com" <dgilbert@redhat.com>

On Tue, Aug 05, 2014 at 04:48:18PM +0100, Alex Benn=E9e wrote:
>=20
> Gonglei (Arei) writes:
>=20
> > Hi,
> >
> >> > Yoda conditions lack readability, and QEMU has a
> >> > strict compiler configuration for checking a common
> >> > mistake like "if (dev =3D NULL)". Make it a written rule.
> <snip>
> >>=20
> >> I know this is my suggested text, but now that I'm re-reading it, I'=
d
> >> recommend s/0/1/ in all three places, since comparison to 0 is one o=
f
> >> those special cases where '!a' is faster to write than 'a =3D=3D 0'.
> >>=20
> > Got it.
>=20
> Should we add explicit examples for:
>=20
> if (x)
> if (!x)
>=20
> then?

Some people prefer a !=3D NULL and not !a.
It's easy to change all =3D=3D NULL and !=3D NULL if
people prefer this:

http://www.emn.fr/z-info/coccinelle/rules/badzero.html



> --=20
> Alex Benn=E9e