Goal:
  
  G : t
  HI : invariants
  HG : acyclic_no_loop
  s : VSet.t
  x : V.t
  e : lsp0 s x x = None
  H : False
  ============================
   (None = Some 0)


DEBUG:Going to execute:
fun => <coq-core.plugins.zify::ITER@0>