auxdir and multiple configure.ac's

[Simon Josefsson]

In GNU SASL I have one top-level configure.ac (for command line tools,
self-tests, etc) and one lib/configure.ac (for the library).  There is
one gnulib m4-base in gl/m4 and one in lib/gl/m4.  Both top-level and
lib/ import the maintainer-makefile module, which is needed for
downloading translations, and because I make releases from both
top-level and lib/ and want some of the release rules in maint.mk.

However, gnulib-tool --import puts build-aux files in the wrong
directory for the lib/gl/m4 base.  The reason is because the --auxdir
variable is read from the top-level configure.ac AC_CONFIG_AUX_DIR.

One work around is to run gnulib-tool --import two times, and in the
second run, specify the --aux-dir parameter explicitly.  However, that
leads to incorrect paths in lib/gl/Makefile.am.

Thoughts on resolving this properly?

My thought is that the machinery to search top-level configure.ac for
AC_CONFIG_AUX_DIR is not worth the trouble, and that we should use the
same machinery for specifying the other directories to gnulib-tool for
build-aux as well.  Opinions?

/Simon