From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jim Meyering <jim@meyering.net>
Subject: Re: general protection faults with "git grep" version 1.7.7.1
Date: Tue, 25 Oct 2011 18:37:19 +0200
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	<201110251550.22248.trast@student.ethz.ch>
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Cc: "Richard W.M. Jones" <rjones@redhat.com>,
	Markus Trippelsdorf <markus@trippelsdorf.de>,
	<git@vger.kernel.org>, "Shawn O. Pearce" <spearce@spearce.org>,
	Jeff King <peff@peff.net>, Nicolas Pitre <nico@fluxnic.net>
To: Thomas Rast <trast@student.ethz.ch>
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Thomas Rast wrote:
> Jim Meyering wrote:
>> Thomas Rast wrote:
>> > [GCC moves access to a file-static variable across pthread_mutex_lock()]
>>
>> Thanks for the investigation.
>> Actually, isn't gcc -O2's code-motion justified?
>> While we *know* that those globals may be modified asynchronously,
>> builtin/grep.c forgot to tell gcc about that.
>
> I'm somewhat unwilling to believe that:

You're right to be skeptical.
I should have stuck with "using volatile works around the problem for me".
The real problem seems to be in glibc, with its addition of
the "leaf" attribute to those synchronization primitives:

  http://bugzilla.redhat.com/747377#c22