Currently, there are only strange parenthesis-related error messages given if an old, incompatible .mod file is used with a newer compiler, e.g.
Fatal Error: Reading module mmm at line 16 column 65: Expected left parenthesis (cf. also PR 38248). The solution is to add a version number which is always bumped if a .mod related change happened, which presumably was the case for all new GCC/gfortran releases. -- Summary: Add version number to .mod file Product: gcc Version: 4.4.0 Status: UNCONFIRMED Keywords: diagnostic Severity: normal Priority: P3 Component: fortran AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: burnus at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38259