src/Tools/WWW_Find/scgi_server.ML

        if length (!threads) < (!max_threads) then ()
        else (tracing ("Waiting for a free thread...");
              ConditionVar.wait (thread_wait, thread_wait_mutex));
        add_thread
          (Thread.fork   (* FIXME avoid low-level Poly/ML thread primitives *)
-            (fn () => ML_Compiler.exn_trace threadf,
+            (fn () => Runtime.exn_trace threadf,
              [Thread.EnableBroadcastInterrupt true,
               Thread.InterruptState
               Thread.InterruptAsynchOnce])))
     end;