Re: Trouble building newer git with older

> Nishanth Aravamudan <nacc@us.ibm.com> writes:
> 
> > This is because GIT-VERSION-GEN attempts to invoke `git describe` but
> > describe is not a valid parameter to the current version of git. This is
> > not treated as a failure case, though, as output is stored in VN.
> > Perhaps the return code of `git describe` should also be checked? Or am
> > I just not supposed to upgrade from this old of a version of git via
> > git?
> 
> No, it was broken when this patch was applied.
> 
>         commit 1100ac81a90b03e0c037a286569a340decf7489b
>         Author: Sean <seanlkml@sympatico.ca>
>         Date:   Mon May 22 00:39:52 2006 -0400
> 
> Luckily, my copy of GNU interactive tools, when invoked like this:
> 
> 	git describe --abbrev=4 HEAD 2>/dev/null
> 
> exits with an error code 1, so the existing code already catches it.
> 
> How about this patch?
> 
> -- >8 --
> GIT-VERSION-GEN: adjust for ancient git
> 
> When an ancient "git" that does not understand "describe"
> command is on the $PATH, "git describe" emitted a Usage message
> without exiting non-zero status (which is a mistake we cannot
> fix retroactively).  Catch this case to make sure we do not try
> using phoney multi-line string as a version number.
> 
> Signed-off-by: Junio C Hamano <junkio@cox.net>