[PPL-devel] User-visible changes to lib-link.m4 and lib-prefix.m4

[Roberto Bagnara]

Hi there,

we have been using the AC_LIB_LINKFLAGS for years without any problem.
A few days ago, that is, a few days before the release of the Parma
Polyhedra Library (http://www.cs.unipr.it/ppl/) we thought it was a good
idea to update lib-link.m4 and lib-prefix.m4, since we were still using the
version distributed with Gettext 0.14.6.  However, this update broke
the build.  Looking at config.log it seems that, despite using the
--with-lib-prefix option, no -I option is added to the compiler options.
We tried to understand what was changed in lib-link.m4 and lib-prefix.m4,
but we failed.  We discovered, though, that things stop working for us
in passing from the versions distributed with with Gettext 0.14.6
to the versions distributed with Gettext 0.15.  We have looked
in the sources and at the NEWS file to understand whether the
AC_LIB_LINKFLAGS should be used differently with the newer versions,
but we failed again.

Here is how we use the AC_LIB_LINKFLAGS macro in an Autoconf macro
by ourselves:

AC_DEFUN([AC_CHECK_GMP],
[
dnl Since libgmp and libgmpxx are usually installed in the same location,
dnl let the prefixes default from each other.
if test -n "$with_libgmpxx_prefix" && test -z "$with_libgmp_prefix"; then
   with_libgmp_prefix="$with_libgmpxx_prefix"
else
   if test -n "$with_libgmp_prefix" && test -z "$with_libgmpxx_prefix"; then
     with_libgmpxx_prefix="$with_libgmp_prefix"
   fi
fi

dnl Check how to link with libgmp.
AC_LIB_LINKFLAGS([gmp])

dnl Check how to link with libgmpxx.
AC_LIB_LINKFLAGS([gmpxx], [gmp])
...

What are we missing?  Is there some documentation on how to properly
use these macros?
All the best,

    Roberto

-- 
Prof. Roberto Bagnara
Computer Science Group
Department of Mathematics, University of Parma, Italy
http://www.cs.unipr.it/~bagnara/
mailto:bagnara at cs.unipr.it