src/Pure/goal.ML

               Theory.subthy (theory_of_thm st, thy) orelse err "Bad background theory of goal state";
             val res =
               (finish ctxt' st
                 |> Drule.flexflex_unique
                 |> Thm.check_shyps sorts
-                (* |> Thm.check_hyps ctxt' *) (* FIXME *))
+                (* |> Thm.check_hyps (Context.Proof ctxt') *) (* FIXME *))
               handle THM (msg, _, _) => err msg | ERROR msg => err msg;
           in
             if Unify.matches_list thy [Thm.term_of stmt] [Thm.prop_of res] then res
             else err ("Proved a different theorem: " ^ Syntax.string_of_term ctxt' (Thm.prop_of res))
           end);