anchor.diff:                  then [Unfold Delta_constant]
                   else [NoDelta] in
               let cfg' = {cfg with steps=s; delta_level=delta_level} in
  -            let stack' = Debug t :: Steps (cfg.steps, cfg.primitive_steps, cfg.delta_level)::stack in
  +            let stack' =
  +              let tail = Steps (cfg.steps, cfg.primitive_steps, cfg.delta_level)::stack in
  +              if Env.debug cfg.tcenv <| Options.Other "print_normalized_terms"
  +              then Debug(t, BU.now())::tail
  +              else tail in
               norm cfg' env stack' tm
   
             | Tm_app({n=Tm_constant FC.Const_reify}, a1::a2::rest) ->
  
positive.code:  | Meta     of S.metadata * Range.range
   | Let      of env * binders * letbinding * Range.range
   | Steps    of steps * list<primitive_step> * list<Env.delta_level>
   | Debug    of term
  
  type stack = list<stack_elt>
  
  
negative.code:     | Meta (m,_) -> "Meta"
      | Let  _ -> "Let"
      | Steps (_, _, _) -> "Steps"
      | Debug (t, _) -> BU.format1 "Debug %s" (Print.term_to_string t)
      // | _ -> "Match"
  
  let stack_to_string s =
  