From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff King <peff@peff.net>
Subject: Re: [PATCH 8/8] Enable GIT_DEBUG_MEMCHECK on git_pathname()
Date: Thu, 17 Nov 2011 08:42:01 -0500
Message-ID: <20111117134201.GA30718@sigill.intra.peff.net>
References: <1321522335-24193-1-git-send-email-pclouds@gmail.com>
 <1321522335-24193-9-git-send-email-pclouds@gmail.com>
 <CALkWK0ndE1Q_jNSV7CBB5W2NyVhcy7kgNO5woWWOw6CXx3cxcA@mail.gmail.com>
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Cc: =?utf-8?B?Tmd1eeG7hW4gVGjDoWkgTmfhu41j?= Duy <pclouds@gmail.com>,
	git@vger.kernel.org, Junio C Hamano <gitster@pobox.com>,
	Michael Haggerty <mhagger@alum.mit.edu>,
	Jonathan Nieder <jrnieder@gmail.com>
To: Ramkumar Ramachandra <artagnon@gmail.com>
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On Thu, Nov 17, 2011 at 04:05:52PM +0530, Ramkumar Ramachandra wrote:

> The macros __FILE__, __LINE__ and __VA_ARGS__ are gcc-specific
> extensions, no?  I was curious to see if some other parts of Git are
> using this: a quick grep returns mailmap.c and notes-merge.c.  They
> both use __VA_ARGS__ it for debugging purposes.  So, nothing new.

All three are in C99. I'm pretty sure __FILE__ and __LINE__ were
available in C89, but I only have a copy of C99 handy these days.
Variable-argument macros were definitely introduced in C99 (and were a
gcc extension for a while before then).

> What happens if GIT_DEBUG_MEMCHECK is set, but I'm not using gcc?
> Also, it's probably worth mentioning in the commit message that this
> debugging trick is gcc-specific.

Older compilers will probably barf on the variable-argument macros.

-Peff