Libtool, multiple languages, and --tag

[Gary Kumfert]

Hi, 

I'm interested in using libtool on C, C++, F77, and F90.
I've got an old, mutilated version that's helped me get 
by 'til now.  But my eyes really lit up when v1.5 advertised
multiple language support!

I've got pieces of a mystery, but no complete story of how
to get this to work.
 1.  Using the new libtool thusly:
        libtool --mode=compile pgf90 -I. -I../../../runtime/sidl -I. -c -o 
SIDL_BaseClass_type.lo SIDL_BaseClass_type.f90
     I get 
        libtool: compile: unable to infer tagged configuration
        libtool: compile: specify a tag with `--tag'

 2.  I think --tag is new with 1.5, perhaps associated with multiple languages?
     If so, how do I use it?
 3.  I searched the online libtool manual for the string "--tag"... nada.   
 4.  In my generated libtool script I found
        # The names of the tagged configurations supported by this script.
        available_tags=" CXX F77"

I'm glad to see (or at least infer from #4) that the advertised
multi language support extends beyond C/C++, but I *really* need to 
get Fortran90 working.

Help, 

Gary

------------------------------------------------------------------------
  Gary Kumfert, Ph.D.                               <address@hidden>
  Center for Applied Scientific Computing          phone: 925-424-2580
  Lawrence Livermore National Laboratory           fax:   925-423-9338
  P.O. Box 808,    L-551
  Livermore, CA 94551-0808