Using __sync_* builtins within libgcc code

Joseph S. Myers joseph@codesourcery.com
Tue Jun 10 14:43:00 GMT 2008


On Tue, 10 Jun 2008, H.J. Lu wrote:

> On Tue, Jun 10, 2008 at 02:27:17PM +0200, Paolo Carlini wrote:
> > Joseph S. Myers wrote:
> >> I hold that it is a bug that i686-* tools default to -march=i386 instead 
> >> of -march=i686 (whereas e.g. sparcv9-* tools default to -mcpu=sparcv9, and 
> >> -mcpu means -march for SPARC).
> > Seconded.
> >
> 
> What arch should be used for -m32 on x86-64? Personally, I think
> it should be at least i686, if not SSE2.

-march=x86-64, I'd say, if you're configuring as x86_64-* (so assuming 
those 32-bit features present on all 64-bit processors).  Obviously, 
subject to override from --with-arch-32 or --with-arch.

-- 
Joseph S. Myers
joseph@codesourcery.com



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