Make #$ truly read-only for Lisp; check this in the test suite. lisp/ChangeLog addition: 2009-02-10 Aidan Kehoe <kehoea@parhasard.net> * automated/lisp-tests.el : Check that #$ is not modifiable from Lisp, and that load-file-name is modifiable from Lisp. src/ChangeLog addition: 2009-02-10 Aidan Kehoe <kehoea@parhasard.net> * lread.c (Fload_internal): Make load-file-name-internal readonly for Lisp code; make load-file-name a modifiable copy. (init_lread): Initialised Vload_file_name_internal, Vload_file_name to nil on each post-dump start.