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Date: Wed, 28 Apr 2021 17:29:14 +0000
From: Joseph Myers <joseph@codesourcery.com>
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To: Paul Zimmermann <Paul.Zimmermann@inria.fr>
CC: Florian Weimer <fweimer@redhat.com>, <libc-alpha@sourceware.org>
Subject: Re: use of fma
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On Wed, 28 Apr 2021, Paul Zimmermann wrote:

> produced should run on any x86_64. What I suggest is a configure option
> which would take advantage of all nice features available on the processor
> where we compile, with no guarantee whatsoever that it runs on any other
> processor. In the above case the -march=x86-64-v3 option would be added

That option is CC="gcc -march=native" (you can pass CC on the configure 
command line, I don't see any need for a separate option for this; note 
that we'd like to phase out the existing --with-cpu option (which affects 
both sysdeps directories and compiler options) and instead purely rely on 
the setting of CC).

-- 
Joseph S. Myers
joseph@codesourcery.com