bug#9106: 24.0.50; ./configure causes massive recompilation

[Ralf Wildenhues]

Hello,

* Eli Zaretskii wrote on Wed, Jul 20, 2011 at 08:29:38AM CEST:
> > From: Paul Eggert <eggert@cs.ucla.edu>
> 
> > And this would occur every time one does a 'make', even when there's
> > no real work to do.
> 
> This occurs already: these headers are regenerated every time I re-run
> the `configure' script.

Yes, but 'make' is run a lot more often than 'configure' in some
workflows.  I think one implicit gnulib expectation is that configure
is not run often.  (FWIW I don't agree, because if your source tree
is several times larger than your gnulib extract, then it really matters
whether you need to rebuild the world even rarely.)

I proposed using stamp files before, but there are (understandable)
reservations against them.

Cheers,
Ralf