From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pierre Habouzit <madcoder@debian.org>
Date: Tue, 05 Jun 2007 11:37:21 +0000
Subject: Re: [KJ] for loops and variable declarations...
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On Tue, Jun 05, 2007 at 06:22:40PM +0700, Kevin Jackson wrote:
> Hi all,
>=20
> I'm just looking at kernel code for basically the first time - so
> please be patient :)
>=20
> I'm seeing this style of code:
>=20
> uchar a
> ....
> ....
> ....
> ....
> ....
> ....(many lines later...)
> for(a=3D2; a< VALUE; a++)
>=20
>=20
> Why are loop variables declared so far away from where they are used?

  because C forbigs in-code variable declarations (unlike C++). GNU C
authorizes it though.

> Is this advantageous in some way?  It seems that the scope of the
> variables is much larger than having them declared just as they are to
> be used eg:
>=20
> for(uchar a=3D2; a<VALUE; a++)

  This for is only allowed in C99, and is not well defined on some
compilers where a scope is not necessarily limited to the for loop as
common sense would suppose.

  So IMHO, kernel do not uses such kind of code (but I may be wrong).

--=20
=C2=B7O=C2=B7  Pierre Habouzit
=C2=B7=C2=B7O                                                madcoder@debia=
n.org
OOO                                                http://www.madism.org

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