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Date: Wed, 06 Nov 2013 15:24:51 +0800
From: David Xu <davidxu@freebsd.org>
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To: FreeBSD Current <freebsd-current@freebsd.org>
Subject: how to know atomic_cmpset_64 is defined
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Hi,

I want to use atomic_cmpset_64, but some arch may not support it,
Is there a way to figure out that atomic_cmpset_64 is defined when
compiling ?

Regards,
David Xu