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Date: Wed, 25 Jun 2014 08:56:00 -0000
Message-ID: <CAFiYyc3Eda-j8CzXDqZqiiB3cY7NsoXU+rq0XYpBky_sNxXziQ@mail.gmail.com>
Subject: Re: [PATCH] Change default for --param allow-...-data-races to off
From: Richard Biener <richard.guenther@gmail.com>
To: Jakub Jelinek <jakub@redhat.com>
Cc: Bernd Edlinger <bernd.edlinger@hotmail.de>, 	"gcc-patches@gcc.gnu.org" <gcc-patches@gcc.gnu.org>
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On Wed, Jun 25, 2014 at 10:54 AM, Jakub Jelinek <jakub@redhat.com> wrote:
> On Wed, Jun 25, 2014 at 10:14:17AM +0200, Richard Biener wrote:
>> > Perhaps not unsurprisingly, the patch is very similar.  Bootstrapped
>> > and tested on x86_64-linux.  OK for trunk?
>>
>> Ok - please give the C++/atomics folks a chance to comment.
>>
>> This change of default behavior should also be documented in
>> gcc-4.10/changes.html.
>
> Do we want to allow the store data races by default with -Ofast even in strict
> conformance modes (-std=c++11, -std=c++14, -std=c11)?

I think so.  -Ofast means -Ofast (same issue with fp contraction and other
stuff -ffast-math enables that is not valid in strict conformance mode).

Richard.