From owner-freebsd-hackers@FreeBSD.ORG  Sun Mar  7 23:38:40 2010
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Date: Sun, 7 Mar 2010 23:21:46 +0100
From: Patrick Lamaiziere <patfbsd@davenulle.org>
To: freebsd-hackers@FreeBSD.ORG
Message-ID: <20100307232146.6b57f610@davenulle.org>
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Subject: Dead store elimination in the kernel?
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Hello,

I'm asking if FreeBSD is safe regarding dead store elimination made by
gcc? 

By example, in crypto drivers, sensitive datas are cleared by a
bzero() after use to avoid potential leakages.  But the bzero() by
itself is useless, is it removed by gcc?

Thanks, regards.