Parsing autoconf input before running aclocal [Was Re: autoreconf and gettext]

[Gary V. Vaughan]

Hi Eric,

On 31 May 2011, at 21:23, Eric Blake <address@hidden> wrote:
> Right now, autoreconf greps configure.ac for /^AM_GNU_GETTEXST_VERSION/,
> rather than using autoconf --trace mechanisms.  Which is unfortunate,
> because for situations like this, it gets the wrong answers.

Sometimes, particularly with bootstrap tools that need to work before all the 
.m4
files required are available, it is not possible to run 'autoconf --trace' 
without
failing on undefined macros.  The solution to that /has/ been to grep through 
the
source files; however, in the replacement bootstrap script I've submitted to
gnulib on a few occasions over the last year, I came up with a much better
mechanism than grep, which uses M4 itself to parse the input files for calls to
important macros, so is not subject to false positives or inability to parse M4
constructed symbols... but which continues to work even which aclocal has not
yet copied the depended upon macro files into view -- unlike Autoconf proper.

This seems like a good mechanism to port to autoreconf IMHO. Or better yet,
for incorporation into Autoconf itself as a separate --language option.

Ping me if you're interested but can't find my relevant posts, and I'll look up
the links for you in the gnulib archives.

Cheers,
-- 
Gary V. Vaughan (gary AT gnu DOT org)