Re: [discuss] RFC: let x86_64 no longer define X86

[Adrian Bunk <bunk@stusta.de>]

On Fri, Nov 19, 2004 at 01:40:55PM +0100, Andi Kleen wrote:

> > The most important improvement would be to prevent such bugs and to have 
> > the X86_64 dependency explicitely stated.
> 
> This would just end up with me having to hunt through all the drivers
> all the time and enabling drivers that need to be enabled on x86-64 too.
> 
> It's much easier to disable the few drivers that are broken with !X86_64. 
>...

The issue you describe only occurs when a new dependency on X86 is 
added. It is not a problem for the common case that a driver is portable 
and therefore available on all architectures.

If the driver also works on X86_64, adding a " || X86_64" is trivial.
In the worst case, a new driver is not available on X86_64 until this is 
added to the dependencies.

But the current setup might cause real bugs.

If one new user of CONFIG_LBD wouldn't additionally (and not strictly 
required) check BITS_PER_LONG, it might currently have unwanted effects 
on X86_64. Explicite annotations with X86_64 if it works on this 
architecture would prevent such bugs.

> -Andi

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