src/HOL/BNF/Tools/bnf_lfp_tactics.ML

     val ks = 1 upto n;
     fun mk_inner_induct_tac induct i =
       EVERY' [rtac allI, fo_rtac induct ctxt,
         select_prem_tac n (dtac @{thm meta_spec2}) i,
         REPEAT_DETERM_N n o
-          EVERY' [dtac meta_mp THEN_ALL_NEW Goal.norm_hhf_tac,
+          EVERY' [dtac meta_mp THEN_ALL_NEW Goal.norm_hhf_tac ctxt,
             REPEAT_DETERM o dtac @{thm meta_spec}, etac (spec RS meta_mp), atac],
         atac];
   in
     EVERY' [rtac rev_mp, rtac (Drule.instantiate' cTs cts ctor_induct),
       EVERY' (map2 mk_inner_induct_tac weak_ctor_inducts ks), rtac impI,