From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH 0/4] drop some "int x = x" hacks to silence gcc warnings
Date: Thu, 21 Mar 2013 07:58:51 -0700
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Cc: Johannes Sixt <j.sixt@viscovery.net>, git@vger.kernel.org
To: Jeff King <peff@peff.net>
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Jeff King <peff@peff.net> writes:

> Git code was my introduction to it, too, and I was led to believe it was
> idiomatic, so I can't speak further on that. I think it was Junio who
> introduced me to it, so maybe he can shed more light on the history.

I think we picked the convention up from the kernel folks.  At least
that is how I first met the construct.  The uninitialized_var(x)
macro was (and still is) used to mark these "The compiler is too
dumb to realize, but we know what we are doing" cases:

    $ git grep '#define uninitialized_var' include/
    include/linux/compiler-gcc.h:#define uninitialized_var(x) x = x
    include/linux/compiler-intel.h:#define uninitialized_var(x) x

but they recently had a discussion, e.g.

    http://thread.gmane.org/gmane.linux.kernel.openipmi/1998/focus=1383705

so...