using CONFIGURE_DEPENDENCIES with autom4te cache

[Asher Gordon]

Greetings,

I am trying to pass the output of a script, using m4_esyscmd, to AC_INIT
as the package version. My script generates the version from `git
describe --always --dirty' or `./configure --version' if git failed
(that way it works even in dist tarballs). I know about git-version-gen
from gnulib, but I don't like how it works, so I wrote my own script.

Anyway, the script works fine, but I'd like to rebuild configure
(i.e. run autoconf) every time build-aux/version-gen (the name of the
script) or .git/HEAD changes. So I added those files to
CONFIGURE_DEPENDENCIES in configure.ac (which I AC_SUBST'd). This works,
but only when autom4te caching is disabled.

From the Automake documentation:

    Be also aware that interactions of [‘CONFIGURE_DEPENDENCIES’] with
    the autom4te cache are quite problematic and can cause subtle
    breakage, so you might want to disable the cache if you want to use
    ‘CONFIGURE_DEPENDENCIES’.

I can disable the autom4te cache for that project by using
./.autom4te.cfg, but I'd rather keep it for its benefits. Is there any
way to work around this without disabling the autom4te cache? And if
not, is there any plan to fix this in Automake and/or Autoconf?

See also the attached example git repository bundle. Use

    $ git clone cfg_deps_test.bundle

to extract it. Read the README file throughout the four commits for more
info.

Thanks for your help,
Asher

P.S. I'm not sure if this is an Automake problem or an Autoconf
problem. Since it's described in the Automake documentation, I assume
it's an Automake problem.

-- 
Hi! I'm a .signature virus! Copy me into your ~/.signature to help me sprea=
d!

cfg_deps_test.bundle
Description: Example git repository illustrating the problems of using CONFIGURE_DEPENDENCIES with the autom4te cache

signature.asc
Description: PGP signature