Re: [PATCH] mv: Fix spurious warning when moving a file in presence of submodules

From: Jonathan Nieder <jrnieder@gmail.com>
Date: Oct 14, 2013, 05:40 UTC
Message-ID: <20131014054048.GC25344@google.com>
In-Reply-To: <vpqr4bp6wkh.fsf@anie.imag.fr>

Matthieu Moy wrote:

> Jens Lehmann <Jens.Lehmann@web.de> writes:

Show 6 quoted lines

>>  static struct lock_file lock_file;
>> +#define SUBMODULE_WITH_GITDIR ((const char *)1)
>
> I don't like very much hardcoded addresses like this. Are you 100% sure
> address 1 will never be returned by xstrdup on any platform? The risk is
> small if not negligible, but I'm unconfortable with this.

I haven't checked what the standards say, but in practice I think it's okay. An alternative would be to do something like

	static const char SUBMODULE_WITH_GITDIR[] = "*** (submodule with gitdir) ***";

which is a bit more error-prone because attempts to use it as a string wouldn't crash. We use (void *) 1 in the same way a few places currently.

Thanks, both.