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Message-ID: <03bb4d4436ca7022effbf23551ada24ff9eeb4c6.camel@perches.com>
Subject: Re: mmc: atmel-mci: Reduce scope for the variable
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From:   Joe Perches <joe@perches.com>
To:     Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc:     Markus Elfring <Markus.Elfring@web.de>, linux-mmc@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        Ludovic Desroches <ludovic.desroches@microchip.com>,
        Nicolas Ferre <nicolas.ferre@microchip.com>,
        Ulf Hansson <ulf.hansson@linaro.org>,
        LKML <linux-kernel@vger.kernel.org>,
        kernel-janitors@vger.kernel.org,
        Colin Ian King <colin.king@canonical.com>,
        Dan Carpenter <dan.carpenter@oracle.com>
Date:   Sat, 12 Dec 2020 10:48:55 -0800
In-Reply-To: <20201212131727.GL1781038@piout.net>
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On Sat, 2020-12-12 at 14:17 +0100, Alexandre Belloni wrote:
> On 12/12/2020 01:16:39-0800, Joe Perches wrote:
> > In this case Alexandre it seems true, but in the generic case
> > it may be false.  It may depend on stack size and location.
> > 
> > For instance, with large structs declared either at the top
> > of a function or in separate branches within the function:
>
> I think you realize your example is way more complicated than
> initializing basic type variable to 0 or NULL which has probably been
> optimized forever.

Maybe.

Markus does a lot of what most (or perhaps some) consider thoughtless.

A generic point might be maximizing the local scope of declarations.

Maximizing the local scope can make reading easier as the type of an
automatic used for a temporary purpose can be found closer to the code
that uses it.  This is especially true for long line-count functions.

IMO: it's a reasonable goal though in this instance perhaps unnecessary.

cheers, Joe