From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff King <peff@peff.net>
Subject: Re: [PATCH v2] format-patch --signature-file <file>
Date: Tue, 20 May 2014 02:21:32 -0400
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Cc: Junio C Hamano <gitster@pobox.com>, git@vger.kernel.org
To: Jeremiah Mahler <jmmahler@gmail.com>
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On Mon, May 19, 2014 at 10:46:21PM -0700, Jeremiah Mahler wrote:

> > Avoiding that is easy with an indirection, no?  Something like this
> > at the top:
> > 
> >   static const char *the_default_signature = git_version_string;
> >   static const char *signature = the_default_signature;
> > 
> > and comparing to see if signature points at the same address as
> > the_default_signature would give you what you want, I think.
> 
> I like your suggestion for a default signature variable.
> Unfortunately, C doesn't like it as much.
> 
> static const char *the_default_signature = git_version_string;
> static const char *signature = the_default_signature;  // ERROR
> // initializer element is not constant

You could do:

  #define DEFAULT_SIGNATURE git_version_string
  static const char *signature = DEFAULT_SIGNATURE;

  ...

  if (signature == DEFAULT_SIGNATURE)
     ...

but maybe that is getting a little unwieldy, considering the scope of
the original problem.

-Peff