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')).