Re: [-mm patch] i386: enable REGPARM by default

[Adrian Bunk <bunk@stusta.de>]

On Sun, May 15, 2005 at 02:22:34PM +0200, Andi Kleen wrote:
> Adrian Bunk <bunk@stusta.de> writes:
> 
> > This patch should _not_ go into Linus' tree.
> >
> > At some time in the future, we want to unconditionally enable REGPARM on 
> > i386.
> >
> > Let's give it a bit broader testing coverage among -mm users.
> 
> iirc problem is that gcc 2.95 and possibly 3.0.x have some known
> miscompilations with regparams. That is why it was only used
> with fastcall for a long time. One 3.1.x+ it should be safe.
> But you cannot express dependencies on the compiler version
> in Kconfig right now.
> 
> Of course getting rid of gcc 2.95 and 3.0.x support would be a good idea,
> that would allow many other nice things.

If you'd read either arch/i386/Makefile or the help text for 
CONFIG_REGPARM, you'd have noticed that we do never use regparm with
gcc < 3.0 .

> -Andi

cu
Adrian

-- 

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       "Only a promise," Lao Er said.
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