Message-ID: <4722265C.7050907@nortel.com>
Date: Fri, 26 Oct 2007 11:39:40 -0600
From: "Chris Friesen" <cfriesen@nortel.com>
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To: Andrew Haley <aph@redhat.com>
CC: Nick Piggin <nickpiggin@yahoo.com.au>, davids@webmaster.com,
       "Torvalds, Linus" <torvalds@linux-foundation.org>,
       "Kleen, Andi" <ak@suse.de>,
       "Linux-Kernel@Vger. Kernel. Org" <linux-kernel@vger.kernel.org>
Subject: Re: Is gcc thread-unsafe?
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Andrew Haley wrote:

> We're listening, really.  It's unacceptable that gcc should break
> code.

In that case a conversion of a conditional branch to an unconditional 
write to a visible variable is not an acceptable behaviour.  Aside from 
the kernel issues, it would break any number of threaded userspace apps.

As was mentioned elsewhere, it's akin to sprinkling

int j = i; i = j;

throughout the code.  If "i" is accessed by multiple threads, this is 
not allowed unless a lock is held.

Chris
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