Re: `aclocaldir' fixed

[Ralf Wildenhues]

[ This is a bug report against libtool, I'm copying automake in order
  to solicit feedback ]

Hi Ilya,

* Ilya N. Golubev wrote on Wed, Oct 05, 2005 at 10:58:31PM CEST:
> 
> `aclocaldir' value is set by `configure' unconditionally.  Can not be
> specified in build configuration explicitly, let alone set
> automatically according to what is used by `aclocal' program.
> 
> Worse, that it should be consistent with what is configured for
> `aclocal' installation is only said as a comment in sources, not in
> libtool installation documentation.

Thanks for this bug report.  I agree this should be fixed, but I am
quite unsure how to go about a good fix.

For example, an el cheapo fix would be like in the patch below: allow
override of aclocaldir like
  configure aclocaldir=/dir [MORE OPTIONS]

But then, we should also document this.  Actually it would be nicest if
this appeared in the output of `./configure --help' alongside the other
`--foodir' options, and also be usable with dashes in front.  This would
be an Autoconf issue -- it does not yet support extending this list at
all.  OTOH this list is huge already, extending it further might not
help the user in the end.

The next issue is an Automake one: should `aclocaldir' by default be,
for example, the value of `aclocal --print-ac-dir'?  That would require
us to allow overriding $ACLOCAL as well, I guess?  Surely one could have
this also by suggesting
  configure aclocaldir=`aclocal --print-ac-dir`
instead, thus saving relying on one more tool.

OTOH, the aclocal path is extendable by using the dirlist, see
  info Automake "Macro search path"
for more information.  Surely this limits user flexibility somewhat.

First, I don't know what I like best, and second, I think maybe there
should be some consistency among packages that install m4 macros; third,
`aclocal' is doomed a bit anyway..  What's the best way?

Cheers,
Ralf

small demo patch against Libtool CVS HEAD:
(similar issue with pkgdatadir, by the way)

Index: configure.ac
===================================================================
RCS file: /cvsroot/libtool/libtool/configure.ac,v
retrieving revision 1.73
diff -u -r1.73 configure.ac
--- configure.ac        26 Sep 2005 12:04:46 -0000      1.73
+++ configure.ac        6 Oct 2005 15:57:57 -0000
@@ -134,7 +134,8 @@
 ## Libtool specific configuration. ##
 ## ------------------------------- ##
 
-AC_SUBST([aclocaldir], ["\${datadir}/aclocal"])
+: ${aclocaldir="\${datadir}/aclocal"}
+AC_SUBST([aclocaldir])
 AC_SUBST([pkgdatadir], ["\${datadir}/$PACKAGE"])
 
 AC_ARG_ENABLE(ltdl-install,