src/Pure/Concurrent/single_assignment.ML

       fun wait () =
         (case peek v of
           NONE =>
             (case Multithreading.sync_wait NONE NONE cond lock of
               Exn.Res _ => wait ()
-            | Exn.Exn exn => reraise exn)
+            | Exn.Exn exn => Exn.reraise exn)
         | SOME x => x);
     in wait () end);
 
 fun assign (v as Var {name, lock, cond, var}) x =
   Multithreading.synchronized name lock (fn () =>