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Date: Fri, 25 Oct 2013 14:26:43 +0200
From: Daniel Hartmeier <daniel@benzedrine.cx>
To: freebsd-hackers@freebsd.org, hackers@freebsd.org
Subject: Re: warning spew from cddl libnvpair.c
Message-ID: <20131025122643.GC12556@insomnia.benzedrine.cx>
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How is that valid?

If nvprt_btwnarrfmt contains %, how would

	(void) fprintf(fp, pctl->nvprt_btwnarrfmt); \

not crash?

And if it may not contain %, why not use

	(void) fprintf(fp, "%s", pctl->nvprt_btwnarrfmt); \

It can be set to arbitrary values with

  libnvpair.c nvlist_prtctl_setfmt()

That's exactly why the compiler warns, no?

If anything in the macro/preprocessor trickery is relevant, I'm not
seeing it.

Daniel