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Date: Thu, 5 Feb 2004 21:04:56 +0100
From: Stefan Farfeleder <stefan@fafoe.narf.at>
To: John Baldwin <john@baldwin.cx>
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References: <20040205164639.GC602@wombat.fafoe.narf.at>
	<200402051405.59533.john@baldwin.cx>
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cc: arch@freebsd.org
Subject: Re: C99 variadic macros
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On Thu, Feb 05, 2004 at 02:05:59PM -0500, John Baldwin wrote:
> On Thursday 05 February 2004 11:46 am, Stefan Farfeleder wrote:

> > #define foo(fmt, args...)	printf("%s: " fmt "\n", __func__, ##args)

> C99 macros don't work when args is 0.  I.e., if I did:
> 
> 	foo("test");
> 
> The C99 _VA_ARGS_ think doesn't delete the , whereas the GCC way does.

While it's true that the ellipsis must match a positive number of
arguments, this isn't necessarily a problem.  You just use "..." for
both the format string and its arguments.

Cheers,
Stefan Farfeleder