Goal:
  
  x : list A.t
  IHx : forall y : t, CompareSpec (x = y) (lt x y) (lt y x) (compare x y)
  t0 : A.t
  y : list A.t
  ============================
   (compare x y = compare x ?y)


DEBUG:Going to execute:
reflexivity
DEBUG LTAC Evaluated term: CompareSpec_Proper
DEBUG LTAC Evaluated term: IHx