diff -r ef876972fdc1 -r 0baa8bbd355a src/Pure/Concurrent/future.ML
--- a/src/Pure/Concurrent/future.ML	Wed Aug 10 15:17:24 2011 +0200
+++ b/src/Pure/Concurrent/future.ML	Wed Aug 10 16:05:14 2011 +0200
@@ -41,9 +41,10 @@
   val is_finished: 'a future -> bool
   val cancel_group: Task_Queue.group -> unit
   val cancel: 'a future -> unit
-  val forks:
-    {name: string, group: Task_Queue.group option, deps: Task_Queue.task list, pri: int} ->
-      (unit -> 'a) list -> 'a future list
+  type fork_params =
+   {name: string, group: Task_Queue.group option, deps: Task_Queue.task list,
+    pri: int, interrupts: bool}
+  val forks: fork_params -> (unit -> 'a) list -> 'a future list
   val fork_pri: int -> (unit -> 'a) -> 'a future
   val fork: (unit -> 'a) -> 'a future
   val join_results: 'a future list -> 'a Exn.result list
@@ -51,9 +52,7 @@
   val join: 'a future -> 'a
   val value: 'a -> 'a future
   val map: ('a -> 'b) -> 'a future -> 'b future
-  val cond_forks:
-    {name: string, group: Task_Queue.group option, deps: Task_Queue.task list, pri: int} ->
-      (unit -> 'a) list -> 'a future list
+  val cond_forks: fork_params -> (unit -> 'a) list -> 'a future list
   val promise_group: Task_Queue.group -> 'a future
   val promise: unit -> 'a future
   val fulfill_result: 'a future -> 'a Exn.result -> unit
@@ -403,7 +402,7 @@
       | Exn.Res _ => true);
   in ok end;
 
-fun future_job group (e: unit -> 'a) =
+fun future_job group interrupts (e: unit -> 'a) =
   let
     val result = Single_Assignment.var "future" : 'a result;
     val pos = Position.thread_data ();
@@ -412,7 +411,9 @@
         val res =
           if ok then
             Exn.capture (fn () =>
-              Multithreading.with_attributes Multithreading.private_interrupts
+              Multithreading.with_attributes
+                (if interrupts
+                 then Multithreading.private_interrupts else Multithreading.no_interrupts)
                 (fn _ => Position.setmp_thread_data pos e ()) before
               Multithreading.interrupted ()) ()
           else Exn.interrupt_exn;
@@ -422,7 +423,11 @@
 
 (* fork *)
 
-fun forks {name, group, deps, pri} es =
+type fork_params =
+ {name: string, group: Task_Queue.group option, deps: Task_Queue.task list,
+  pri: int, interrupts: bool};
+
+fun forks ({name, group, deps, pri, interrupts}: fork_params) es =
   if null es then []
   else
     let
@@ -432,7 +437,7 @@
         | SOME grp => grp);
       fun enqueue e queue =
         let
-          val (result, job) = future_job grp e;
+          val (result, job) = future_job grp interrupts e;
           val (task, queue') = Task_Queue.enqueue name grp deps pri job queue;
           val future = Future {promised = false, task = task, result = result};
         in (future, queue') end;
@@ -447,7 +452,9 @@
         in futures end)
     end;
 
-fun fork_pri pri e = singleton (forks {name = "", group = NONE, deps = [], pri = pri}) e;
+fun fork_pri pri e =
+  singleton (forks {name = "", group = NONE, deps = [], pri = pri, interrupts = true}) e;
+
 fun fork e = fork_pri 0 e;
 
 
@@ -513,7 +520,7 @@
   let
     val task = task_of x;
     val group = Task_Queue.new_group (SOME (Task_Queue.group_of_task task));
-    val (result, job) = future_job group (fn () => f (join x));
+    val (result, job) = future_job group true (fn () => f (join x));
 
     val extended = SYNCHRONIZED "extend" (fn () =>
       (case Task_Queue.extend task job (! queue) of
@@ -523,8 +530,8 @@
     if extended then Future {promised = false, task = task, result = result}
     else
       singleton
-        (forks {name = "Future.map", group = SOME group,
-          deps = [task], pri = Task_Queue.pri_of_task task})
+        (forks {name = "Future.map", group = SOME group, deps = [task],
+          pri = Task_Queue.pri_of_task task, interrupts = true})
         (fn () => f (join x))
   end;