Goal:
  
  G : t
  invG : invariants G
  acG : acyclic_no_loop' G
  x : V.t
  s : VSet.t
  p : SPath G s x x
  wp : sweight p > 0
  ============================
   (sweight p > 0)


DEBUG:Going to execute:
trivial; hnf; intros; (solve
            [ do
            ![ solve
             [ trivial | apply : eq_sym ; trivial ]
             | discriminate
             | contradiction
             | Ltac.split ]
            | case not_locked_false_eq_true; Ltac.assumption
            | match goal with
              | H:~ _ |- _ => solve [ case H; trivial ]
              end ])