Re: [PATCH] trivial: the memset operation on a automatic arrayvariable should be optimized out by data initialization

From: Adrian Bunk
Date: Sat Jun 23 2007 - 09:13:46 EST


On Sat, Jun 23, 2007 at 09:59:33AM +0200, Oleg Verych wrote:
> * From: Denis Cheng
> * Newsgroups: linux.kernel
> * Date: Fri, 22 Jun 2007 22:15:49 -0700 (PDT)
>
> > From: Denis Cheng <crquan@xxxxxxxxx>
> >
> > the explicit memset call could be optimized out by data initialization,
> > thus all the fill working can be done by the compiler implicitly.
>
> Can be optimized and can be done by compiler are just words;
>
> > and C standard guaranteed all the unspecified data field initialized to zero.
>
> standards and implementation are on opposite poles of magnet

Bullshit.

We expect a C compiler, and if a C compiler violates the C standard
that's a bug in the compiler that has to be fixed.

And gcc is usually quite good in following the C standard.

> > Signed-off-by: Denis Cheng <crquan@xxxxxxxxx>
> >
> > ---
> > After comments in the former threads:
> > http://lkml.org/lkml/2007/6/18/119
>
> i see a patch
>
> > http://lkml.org/lkml/2007/6/18/48
>
> same patch.
>...

Open your eyes and you'll find thread overviews at the left side of
the URLs he gave...

cu
Adrian

--

"Is there not promise of rain?" Ling Tan asked suddenly out
of the darkness. There had been need of rain for many days.
"Only a promise," Lao Er said.
Pearl S. Buck - Dragon Seed

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