Inductive plus: state -> state -> Prop :=
  | plus_left: forall s1 s2 s3,
      CCstep s1 s2 -> star s2 s3 -> plus s1 s3.Inductive plus: state -> state -> Prop :=
  | plus_left: forall s1 s2 s3,
      CCstep s1 s2 -> star s2 s3 -> plus s1 s3.

Lemma match_find_label: forall lbl k' s1 k0 k0', match_cont (strip_skip k0) (strip_skip' k0') -> (find_label lbl s1 k0 = Some k' -> exists s2 : statement, exists k2' : CC.cont, CC.find_label lbl s1 k0' = Some (s2, k2') /\ match_cont k' (CC.Kseq s2 k2')) with match_find_label_ls: forall lbl k' s1 k0 k0', match_cont (strip_skip k0) (strip_skip' k0') -> (find_label_ls lbl s1 k0 = Some k' -> exists s2 : statement, exists k2' : CC.cont, CC.find_label_ls lbl s1 k0' = Some (s2, k2') /\ match_cont k' (CC.Kseq s2 k2')).