diagnostic.c (trim_filename, [...]): Moved here from rtl.c.
* diagnostic.c (trim_filename, fancy_abort): Moved here from
rtl.c.
(fatal_function, set_fatal_function): Removed.
(fatal): Don't prepare for or call the fatal_function.
(diagnostic_lock, error_recursion): New.
(diagnostic_for_decl, report_diagnostic): Guard against
re-entering the error reporting routines.
(fancy_abort): Assume function is not NULL.
* errors.c (fancy_abort): New. Assume function is not NULL.
* tradcpp.c (fancy_abort): Assume function is not NULL.
* system.h: Provide default definition of __FUNCTION__.
* rtl.h: Use __FUNCTION__ not __PRETTY_FUNCTION__ throughout.
Always use __FUNCTION__ in definition of abort.
* tree.h: Likewise.
* varray.h: Likewise.
* toplev.h: Likewise. Don't prototype set_fatal_function.