Goal:
    G : t  HI : invariants  z : Z  y : Nbar.t  H : 0 <= z
  ============================
   (Z.of_nat (to_label (max (Some z) y)) =
    Z.max (Z.of_nat (to_label (Some z))) (Z.of_nat (to_label y)))


DEBUG:Going to execute:
destruct y
DEBUG LTAC Evaluated term: Nat2Z.inj_max
DEBUG LTAC Evaluated term: Nat2Z.inj_max

Goals:
    G : t  HI : invariants  z : Z  z0 : Z  H : 0 <= z
  ============================
   (Z.of_nat (to_label (max (Some z) (Some z0))) =
    Z.max (Z.of_nat (to_label (Some z))) (Z.of_nat (to_label (Some z0))))

    G : t  HI : invariants  z : Z  H : 0 <= z
  ============================
   (Z.of_nat (to_label (max (Some z) None)) =
    Z.max (Z.of_nat (to_label (Some z))) (Z.of_nat (to_label None)))


DEBUG:Going to execute:
cbn-[to_label]
DEBUG LTAC Evaluated term: y