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To: attilio@FreeBSD.org
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Tue, 18 Sep 2012 17:10:44 +0100."
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Date: Tue, 18 Sep 2012 16:12:56 +0000
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Cc: arch@FreeBSD.org
Subject: Re: Aliasing issue with TAILQ on ppc64 ?
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In message <CAJ-FndDP3RSjgL_fXap2DyDZdXW3iQ_=jnAx_cCx5uFhFeaq5w@mail.gmail.com>
, Attilio Rao writes:

>Stop acting like the old teacher speaking to stupid students.

A very apt metaphor in this case.

Adding memory barriers to the TAILQ macros is not something I would
do lightly, but it is, obviously, one of the possibilties.

I'd far prefer if we could get away with sticking a couple of
volatile's in there.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.