Source_file *sf = ps->start_location_.get_source_file ();
SCM port = sf->get_port ();
- int off = ps->start_location_.start () - sf->c_str ();
+ long off = ps->start_location_.start () - sf->c_str ();
scm_seek (port, scm_from_long (off), scm_from_long (SEEK_SET));
SCM from = scm_ftell (port);