The dependencies of Fortran libraries on other Fortran libraries must be PUBLIC

If Fortran module A uses module (even privately) B:

• some compilers (e.g. NAG) will insist on b.mod being available (e.g. via the -I flag) whenever A is used;
• some compilers (e.g. Cray) will insist on b.o being available (e.g. via the -l flag) whenever A is used.

Hence, if a Fortran library depends on another Fortran library, the dependency has to be PUBLIC, which is not currently the case (e.g. see here). It would be great to fix that.