Goal:
    G : t  HI : invariants G  HG : acyclic_no_loop G  b : bool
  ============================
   (~~ b <-> ~ b)


DEBUG:Going to execute:
fun flags solver =>
             <Coq.Init.Tauto.tauto_intuit> flags
              ltac:(<Coq.Init.Tauto.reduction_not_iff>) solver