Re: Fortran 90/95 support (autoconf)

[Steven G. Johnson]

Chris wrote:
> Essentially, all macros are plain copies of the Fortran 77 versions,
> edited manually to avoid unwanted interactions between them, and to
> adjust default settings.

Please, can we avoid copy-and-paste reuse?  To the degree to which macros
are similar, they should share the same code.

This is especially true for things like AC_F77_LIBRARY_LDFLAGS,
AC_F77_WRAPPERS, which you seem to have copied essentially verbatim.  
Even things like AC_PROG_F77 and AC_PROG_F90, however, should share as
much as possible.  For example, AC_PROG_F77 should call AC_PROG_F90 if it
can't find an F77 compiler, and the latter should in turn call
AC_PROG_F95.

I'm also skeptical of LD9[05]FLAGS.  Autoconf uses a single LDFLAGS for
every other language; why should F9[05] be different?

Honestly, I'd be more inclined to set a Fortran "flavor" in one place, by
calling AC_PROG_{F77,F90,F95} which sets a Fortran compiler FC, and having
most of the other Fortran macros be generic depending only upon the
Fortran compiler that was selected.  It is hard for me to imagine a
project that would mix, say, f90 and f77, and which would not be willing
to use the f90 compiler for the f77 stuff.

Steven