From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andres Salomon <dilinger-pFFUokh25LWsTnJN9+BGXg@public.gmane.org>
Subject: Re: [PATCH 3/3] x86: OLPC: speed up device tree creation during
	boot (v2)
Date: Thu, 18 Nov 2010 09:41:53 -0800
Message-ID: <20101118094153.4515cbc2@queued.net>
References: <20101111214546.4e573cad@queued.net> <reply-olpc-3-v2@mdm.bga.com>
	<20101112002704.50c629e2@queued.net>
	<20101114095013.GB24206@elte.hu> <4CE0B54E.6000101@zytor.com>
	<20101115070254.GA25243@elte.hu> <4CE17133.2050101@zytor.com>
	<20101118083420.GC26398@elte.hu>
	<1290078135.22575.4.camel@concordia> <4CE54064.6010702@zytor.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Return-path: <devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org>
In-Reply-To: <4CE54064.6010702-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>
List-Unsubscribe: <https://lists.ozlabs.org/options/devicetree-discuss>,
	<mailto:devicetree-discuss-request-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org?subject=unsubscribe>
List-Archive: <http://lists.ozlabs.org/pipermail/devicetree-discuss>
List-Post: <mailto:devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org>
List-Help: <mailto:devicetree-discuss-request-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org?subject=help>
List-Subscribe: <https://lists.ozlabs.org/listinfo/devicetree-discuss>,
	<mailto:devicetree-discuss-request-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org?subject=subscribe>
Sender: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org
Errors-To: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org
To: "H. Peter Anvin" <hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>
Cc: devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Milton Miller <miltonm-ogEGBHC/i9Y@public.gmane.org>, Ingo Molnar <mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Ingo Molnar <mingo-X9Un+BFzKDI@public.gmane.org>, Thomas Gleixner <tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org>
List-Id: devicetree@vger.kernel.org

On Thu, 18 Nov 2010 07:04:04 -0800
"H. Peter Anvin" <hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org> wrote:

> On 11/18/2010 03:02 AM, Michael Ellerman wrote:
> > On Thu, 2010-11-18 at 09:34 +0100, Ingo Molnar wrote:
> >>
> >> Look at the general balance of hardship: very little harm is done
> >> (it's not a big deal if a variable is only used in a single
> >> function) but having it with local variables can be _really_
> >> harmful - for example i overlooked them when i reviewed this
> >> patch. I dont like important details obscured - i like them to be
> >> apparent. Again, this is something that some people can parse
> >> immediately on the visual level 
> >> - me and many others cannot.
> > 
> 
> No, sorry, this sounds like a personal preference that is well out of
> line with the vast majority of C programmers I've ever come across,
> not just in the Linux kernel world but outside of it.


This is actually one of the reasons I specifically like initialized
static variables (inside of functions).  Take the following code:

int foo(void)
{
	static char *frob = NULL;
	int p;

	if (frob) {
		...
	}


Upon seeing that and thinking "whoa, how could frob be
initialized and then checked?", I realize that it's either a bug or I
look back at the initialization and realize that frob is static.  It's
less obvious (to me) with non-explicit initialization.