let error_trace sys faulty =
if not quiet then
match Forward.replay_history sys faulty with
| None ->
printf "@\n@{<fg_red>Spurious trace@}\n@.";
raise Exit
| Some trace ->
printf "@\n@{<fg_red>Error trace@}: ";
(* printf "@[%a@]@." (print_trace faulty) trace *)
printf "@[%a@]@." print_history faulty