diff -r 8bef51521f21 -r 146757999c8d src/Pure/Tools/debugger.ML
--- a/src/Pure/Tools/debugger.ML	Mon Jan 08 22:36:02 2018 +0100
+++ b/src/Pure/Tools/debugger.ML	Mon Jan 08 23:45:43 2018 +0100
@@ -276,7 +276,7 @@
             if Command.eval_finished eval then
               let
                 val st = Command.eval_result_state eval;
-                val ctxt = Toplevel.presentation_context_of st
+                val ctxt = Toplevel.presentation_context st
                   handle Toplevel.UNDEF => err ();
               in
                 (case ML_Env.get_breakpoint (Context.Proof ctxt) breakpoint of