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Date: Fri, 25 Mar 2011 15:46:00 -0000
Message-ID: <AANLkTimAypgNnemmG8q3UTEp=mv3bovaO973P4LT1heT@mail.gmail.com>
Subject: Re: [cxx-mem-model] disallow load data races (1 of some)
From: Richard Guenther <richard.guenther@gmail.com>
To: Jakub Jelinek <jakub@redhat.com>
Cc: Jeff Law <law@redhat.com>, Michael Matz <matz@suse.de>, Aldy Hernandez <aldyh@redhat.com>, 	Andrew MacLeod <amacleod@redhat.com>, "Joseph S. Myers" <joseph@codesourcery.com>, 	Richard Henderson <rth@redhat.com>, gcc-patches <gcc-patches@gcc.gnu.org>
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On Fri, Mar 25, 2011 at 4:33 PM, Jakub Jelinek <jakub@redhat.com> wrote:
> On Fri, Mar 25, 2011 at 09:30:22AM -0600, Jeff Law wrote:
>> I'm not going to chime in on this specific problem; however, it is worth
>> noting that many of the issues raised by the C++0x memory model also
>> affect the linux kernel.
>
> But what they are seeing are certainly store data races, not load races,
> because no hw they care about (or no hw at all?) detects the latter.
> Having options to avoid store data races is useful not just for C++0x memory
> model compliance and Linux kernel, but e.g. for OpenMP too.

And we have in the past removed code that created store data races
anyway.  There is nothing new here.

As stated multiple times in the past things get "interesting" when you
look at non-x86 hardware.

Richard.