Re: [PATCH] Re: [PATCH 4/4 v2] [RFC] UIO: generic platform driver

[Russell King - ARM Linux <linux@arm.linux.org.uk>]

On Mon, Apr 14, 2008 at 01:20:21PM +0200, Uwe Kleine-König wrote:
> [1] http://lkml.org/lkml/2008/4/11/81 or
> http://thread.gmane.org/gmane.linux.kernel/665257

In one of the mails, it was said:
  No. It's more important to see which variables are declared in the
  function and which are declared elsewhere. If you have to search the
  whole body of a function for possible declarations, this is BAD. And if
  it's not clear where a variable is used, the function is too long or has
  other style problems. Your function is short and clean, so where's the
  problem? Please move the declaration to the top of the function.

I disagree with this statement.  It's far better to limit the scope of
variables so that you know they only have local use, and eg, not used
inside a loop and then outside with possible unintended effects.

If a variable is only used inside a loop, it should be declared _inside_
that loop.

The statement goes on to talk about the function being short and clean -
that's not an argument to apply any particular point of view on this
subject, since you can argue that because it's short and clean you can
see that the variable is only used within the loop.

So, please, keep the variable declaration inside the loop, and don't
pollute the outer levels with unnecessary variable declarations.