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Date: Thu, 7 Jul 2005 00:13:57 -0700 (PDT)
From: Dmitry Torokhov <dtor_core@ameritech.net>
Subject: Re: Patch of a new driver for kernel 2.4.x that need review
To: Pekka J Enberg <penberg@cs.helsinki.fi>
Cc: Mark Gross <mgross@linux.intel.com>, Willy Tarreau <willy@w.ods.org>,
       Pekka Enberg <penberg@gmail.com>,
       "Bouchard, Sebastien" <Sebastien.Bouchard@ca.kontron.com>,
       "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
       "Lorenzini, Mario" <mario.lorenzini@ca.kontron.com>
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Hi Pekka,

Pekka J Enberg <penberg@cs.helsinki.fi> wrote:
> Hi Dmitry, 
> 
> Mark Gross writes:
> > > > +
> > > > +/* 0 = Dynamic allocation of the major device number */
> > > > +#define TLCLK_MAJOR 252
> 
> Pekka J Enberg <penberg@cs.helsinki.fi> wrote:
> > > Enums, please. 
> > > 
> 
> Dmitry Torokhov writes:
> > But not here - it is a single constant, not a value of a distinct type.
> 
> Fair enough, "static const int" would work here too. Defines should be 
> avoided because they allow you to override a value without ever noticing it.
> 

Would not this cause compiler to allocate memory for the constant?
I suppose if GCC is really good it could eliminate allocation since
nothing takes its address, but I am not sure.

With #define you can be sure that it is just a constant expression.

-- 
Dmitry