From: John W. Linville <linville@tuxdriver.com>
To: Fabian Frederick <fabf@skynet.be>
Cc: Julian Calaby <julian.calaby@gmail.com>,
Johannes Berg <johannes.berg@intel.com>,
linux-wireless <linux-wireless@vger.kernel.org>,
Larry Finger <Larry.Finger@lwfinger.net>,
Chaoming Li <chaoming_li@realsil.com.cn>,
netdev <netdev@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Emmanuel Grumbach <emmanuel.grumbach@intel.com>,
b43-dev <b43-dev@lists.infradead.org>,
Stefano Brivio <stefano.brivio@polimi.it>,
Intel Linux Wireless <ilw@linux.intel.com>
Subject: [PATCH 1/1 net-next] wireless: remove unnecessary sizeof(u8)
Date: Mon, 17 Nov 2014 08:36:19 -0500 [thread overview]
Message-ID: <20141117133618.GC3511@tuxdriver.com> (raw)
In-Reply-To: <828430032.148603.1416203787175.open-xchange@webmail.nmp.skynet.be>
On Mon, Nov 17, 2014 at 06:56:27AM +0100, Fabian Frederick wrote:
>
>
> > On 16 November 2014 at 23:33 Julian Calaby <julian.calaby@gmail.com> wrote:
> >
> >
> > Hi Fabian,
> >
> > On Sat, Nov 15, 2014 at 7:55 AM, Fabian Frederick <fabf@skynet.be> wrote:
> > > sizeof(u8) is always 1.
> >
> > I thought that sizeof(*variable) was preferred over sizeof(type), so
> > shouldn't these be switched to that format instead?
> >
> > (I know that this is all no-op, but it should reduce the potential for
> > highly unlikely bugs in the future. Also, the extra processing is
> > compile-time not run-time.)
> >
> > Thanks,
>
> Hi Julian,
>
> Of course but char/u8/s8... allocations never use it and result would be the
> same:
> factor 1 multiplication.
>
> Those rare occurrences (+- 30 in the whole kernel) where we have
> sizeof(u8/s8) is ambiguous.
>
> Having a patch removing it gives a pointer...
> If the developer meant something else, he will be able to fix it.
>
> Regards,
> Fabian
sizeof(*variable) still seems safer. Are the compilers unable to
optimize-away a "multiply by one"?
John
--
John W. Linville Someday the world will need a hero, and you
linville at tuxdriver.com might be all we have. Be ready.
WARNING: multiple messages have this Message-ID (diff)
From: "John W. Linville" <linville@tuxdriver.com>
To: Fabian Frederick <fabf@skynet.be>
Cc: Julian Calaby <julian.calaby@gmail.com>,
Johannes Berg <johannes.berg@intel.com>,
linux-wireless <linux-wireless@vger.kernel.org>,
Larry Finger <Larry.Finger@lwfinger.net>,
Chaoming Li <chaoming_li@realsil.com.cn>,
netdev <netdev@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Emmanuel Grumbach <emmanuel.grumbach@intel.com>,
b43-dev <b43-dev@lists.infradead.org>,
Stefano Brivio <stefano.brivio@polimi.it>,
Intel Linux Wireless <ilw@linux.intel.com>
Subject: Re: [PATCH 1/1 net-next] wireless: remove unnecessary sizeof(u8)
Date: Mon, 17 Nov 2014 08:36:19 -0500 [thread overview]
Message-ID: <20141117133618.GC3511@tuxdriver.com> (raw)
In-Reply-To: <828430032.148603.1416203787175.open-xchange@webmail.nmp.skynet.be>
On Mon, Nov 17, 2014 at 06:56:27AM +0100, Fabian Frederick wrote:
>
>
> > On 16 November 2014 at 23:33 Julian Calaby <julian.calaby@gmail.com> wrote:
> >
> >
> > Hi Fabian,
> >
> > On Sat, Nov 15, 2014 at 7:55 AM, Fabian Frederick <fabf@skynet.be> wrote:
> > > sizeof(u8) is always 1.
> >
> > I thought that sizeof(*variable) was preferred over sizeof(type), so
> > shouldn't these be switched to that format instead?
> >
> > (I know that this is all no-op, but it should reduce the potential for
> > highly unlikely bugs in the future. Also, the extra processing is
> > compile-time not run-time.)
> >
> > Thanks,
>
> Hi Julian,
>
> Of course but char/u8/s8... allocations never use it and result would be the
> same:
> factor 1 multiplication.
>
> Those rare occurrences (+- 30 in the whole kernel) where we have
> sizeof(u8/s8) is ambiguous.
>
> Having a patch removing it gives a pointer...
> If the developer meant something else, he will be able to fix it.
>
> Regards,
> Fabian
sizeof(*variable) still seems safer. Are the compilers unable to
optimize-away a "multiply by one"?
John
--
John W. Linville Someday the world will need a hero, and you
linville@tuxdriver.com might be all we have. Be ready.
next prev parent reply other threads:[~2014-11-17 13:36 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-14 20:55 [PATCH 1/1 net-next] wireless: remove unnecessary sizeof(u8) Fabian Frederick
2014-11-16 22:33 ` Julian Calaby
2014-11-16 22:33 ` Julian Calaby
2014-11-17 5:56 ` Fabian Frederick
2014-11-17 5:56 ` Fabian Frederick
2014-11-17 13:36 ` John W. Linville [this message]
2014-11-17 13:36 ` John W. Linville
[not found] ` <CAFpvzpxYrjR_tSF99iosMGZTAmt=_6o_aA+iYjNhxRGJ9aJ6oA@mail.gmail.com>
2014-11-18 16:12 ` Larry Finger
2014-11-18 16:12 ` Larry Finger
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