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Date:   Mon, 5 Oct 2020 11:53:10 -0400
From:   Alan Stern <stern@rowland.harvard.edu>
To:     Luc Maranget <luc.maranget@inria.fr>
Cc:     Akira Yokosawa <akiyks@gmail.com>,
        "Paul E. McKenney" <paulmck@kernel.org>, parri.andrea@gmail.com,
        will@kernel.org, peterz@infradead.org, boqun.feng@gmail.com,
        npiggin@gmail.com, dhowells@redhat.com, j.alglave@ucl.ac.uk,
        dlustig@nvidia.com, joel@joelfernandes.org,
        viro@zeniv.linux.org.uk, linux-kernel@vger.kernel.org,
        linux-arch@vger.kernel.org
Subject: Re: Bug in herd7 [Was: Re: Litmus test for question from Al Viro]
Message-ID: <20201005155310.GH376584@rowland.harvard.edu>
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 <20201003132212.GB318272@rowland.harvard.edu>
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On Mon, Oct 05, 2020 at 05:15:57PM +0200, Luc Maranget wrote:
> > On Sun, Oct 04, 2020 at 12:16:31AM +0900, Akira Yokosawa wrote:
> > > > P1(int *x, int *y)
> > > > {
> > > > 	WRITE_ONCE(*x, READ_ONCE(*y));
> > > 
> > > Looks like this one-liner doesn't provide data-dependency of y -> x on herd7.
> > 
> > You're right.  This is definitely a bug in herd7.
> > 
> > Luc, were you aware of this?
> 
> Hi Alan,
> 
> No I was not aware of it. Now I am, the bug is normally fixed in the master branch of herd git deposit.
> <https://github.com/herd/herdtools7/commit/0f3f8188a326d5816a82fb9970fcd209a2678859>
> 
> Thanks for the report.

I tested the new commit -- it does indeed fix the problem.

Thanks.

Alan