Goal:
    x : V.t  n : Z  y : V.t  H0 : V.eq x x  H : n = n  H2 : V.lt y y
  ============================
   False


DEBUG:Going to execute:
PTRDEBUGTACfun flags =>
             match reverse goal with
             | |- ?X1 =>
                   <Coq.Init.Tauto.is_unit_or_eq> flags X1; constructor 1
             | H:?X1 |- _ => <Coq.Init.Tauto.is_empty> flags X1; elim H
             | _ => Ltac.assumption
             end