Libtool makes configure scripts check for unneeded compilers

[Peter Eisentraut]

I'm using

Autoconf 2.57
Automake 1.7.5
Libtool 1.5

The following is the configure.ac:

AC_INIT(foo, 1.0, [me])
AM_INIT_AUTOMAKE
AC_CONFIG_SRCDIR(foo.c)

AM_MAINTAINER_MODE

AC_PROG_CC
AC_DISABLE_STATIC
AC_PROG_LIBTOOL
AC_SUBST(LIBTOOL_DEPS)

AC_CONFIG_FILES(Makefile)
AC_OUTPUT

For some reason this causes libtool(?) to include support for C++ and
Fortran in the resulting configure script.  For example, I see in
'configure':

tagnames=`echo "$tagnames,CXX" | sed 's/^,//'`

tagnames=`echo "$tagnames,F77" | sed 's/^,//'`

And when I run it it checks for g++ and g77 and runs the whole libtool
test range for those compilers.  Does anyone know why?

-- 
Peter Eisentraut   address@hidden