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Re: [RFC PATCH, i386]: Remove special PIC related __cpuid definitions from config/i386/cpuid.h


On Thu, Oct 16, 2014 at 11:19:49AM +0200, Uros Bizjak wrote:
> Hello!
> 
> Now that %ebx is also allocatable in PIC modes, we can cleanup
> config/i386/cpuid considerably. I propose to remove all PIC related
> specializations of __cpuid and __cpuid_count and protect the
> compilation with "#if __GNUC__ >= 5".
> 
> The only drawback would be that non-bootstrapped build with gcc < 5.0
> will ignore -march=native, but I think this should be acceptable.

I'm worried about that.
Can't you instead keep the current cpuid.h stuff as is, just add
&& __GNUC__ < 5
to that, so it treats GCC 5+ PIC as if __PIC__ wasn't defined?

Or, at least use cpuid.h even for older GCC if __PIC__ is not defined
(or __x86_64__ is defined and not medium/large PIC model)?

	Jakub


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