From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff King <peff@peff.net>
Subject: Re: [PATCH 01/41] usage.c: move format processing out of die_errno()
Date: Tue, 3 May 2016 00:45:28 -0400
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On Mon, May 02, 2016 at 11:26:02AM -0700, Junio C Hamano wrote:

> Caller supplied buffer would be the way to go when multiple threads
> could be showing errors and warnings, right?
> 
> It would not make too much of a difference for die(), though.

I think it can matter for die(). This is happening above the pluggable
die_routine() layer, so it's possible for an async task to call die()
which will end in pthread_exit(), while the main program is calling
die() to end in regular exit().

I imagine it's exceedingly unlikely, and of course both threads are
dying anyway, but it could result in some pretty weird memory errors.
It's probably worth taking precautions against, especially because it's
to easy to do so.

-Peff