Location for Fortran90 module files

[Michael Banck <mbanck@debian.org>]

Hi,

Fortran90 compiler produce module files (.mod) when compiling modules,
those are supposed to included by Fortran90 applications like .h header
files for C/C++.

However, those module files are kinda precompiled and compiler- and even
compiler-version dependent in the sense that there is no guarantee that
.mod files from gfortran-4.4 will work with gfortran-4.7.  Point
releases are supposed to be compatible though.

Question is: Are there any such libraries in the archive already (there
are .mod files in the archive, but I couldn't find any obvious Fortran90
.mod files with a quick search), and/or do we have a policy on where to
put those .mod files?

Candidate locations would be:

/usr/include (but those are really meant for C/C++)
/usr/lib/fortran/<compiler-version>
/usr/lib/modules
/usr/include/modules
/usr/finclude (for fortran include, but not FHS compliant I guess)
[...]

Another option would be to use the internal GCC .mod directory, in my
case:

$ gcc -print-file-name=finclude
/usr/lib/gcc/x86_64-linux-gnu/4.7/finclude

What to do about the compatibilty is a different matter, did this come
up before?

For reference, see also the Fedora thread here and the thread on the GCC
list referenced therein:

https://lists.fedoraproject.org/pipermail/packaging/2007-October/003930.html

http://gcc.gnu.org/ml/fortran/2007-10/msg00306.html


Cheers,

Michael