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Date: Mon, 16 Jan 2012 18:39:40 +1100
From: Lawrence Stewart <lstewart@freebsd.org>
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To: David Xu <davidxu@FreeBSD.org>
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Cc: svn-src-head@FreeBSD.org, svn-src-all@FreeBSD.org,
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Subject: Re: svn commit: r230201 - head/lib/libc/gen
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On 01/16/12 17:15, David Xu wrote:
> Author: davidxu
> Date: Mon Jan 16 06:15:14 2012
> New Revision: 230201
> URL: http://svn.freebsd.org/changeset/base/230201
>
> Log:
>    Insert read memory barriers.
>
> Modified:
>    head/lib/libc/gen/sem.c
>    head/lib/libc/gen/sem_new.c

Could you please provide a bit more information about why these are 
necessary and why they weren't there before (or how you figured out that 
there was a problem without them)? I learn a lot by reading commit mail, 
but only when the log message and any added code comments explain the 
"what" *and* the "why".

Cheers,
Lawrence