From owner-freebsd-hackers@FreeBSD.ORG  Wed Jun  3 20:32:49 2015
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Date: Wed, 3 Jun 2015 22:32:28 +0200
From: Joerg Sonnenberger <joerg@britannica.bec.de>
To: freebsd-hackers@freebsd.org
Subject: Re: [PATCH] timecounters: Fix timehand generation read/write
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On Wed, Jun 03, 2015 at 01:46:06PM +0200, Sebastian Huber wrote:
> The compiler is free to re-order load/store instructions to non-volatile
> variables around a load/store of a volatile variable.

This part is wrong. The *compiler* is not free to do such reorder. The
CPU may, as it doesn't really care about volatile.

Joerg