create-fiber always captures dynamic state

* fibers/internal.scm (create-fiber): Remove dynamic-state argument;
  always capture the current dynamic state.
* fibers/timers.scm (timer-operation):
* fibers.scm (spawn-fiber): Adapt.

3 files changed, 12 insertions, 13 deletions

diff --git a/fibers.scm b/fibers.scm
index 270c912..2f7c997 100644
--- a/fibers.scm
+++ b/fibers.scm
@@ -108,8 +108,7 @@
           (vector-ref remote idx))))
   (define (spawn sched thunk)
     (create-fiber (if parallel? (choose-sched sched) sched)
-                  thunk
-                  (current-dynamic-state)))
+                  thunk))
   (cond
    (sched
     ;; When a scheduler is passed explicitly, it could be there is no
diff --git a/fibers/internal.scm b/fibers/internal.scm
index c4d75a6..99727f6 100644
--- a/fibers/internal.scm
+++ b/fibers/internal.scm
@@ -333,17 +333,18 @@ stolen."
   (for-each kill-fiber (list-copy (scheduler-fibers sched)))
   (epoll-destroy (scheduler-epfd sched)))
 
-(define (create-fiber sched thunk dynamic-state)
+(define (create-fiber sched thunk)
   "Spawn a new fiber in @var{sched} with the continuation @var{thunk}.
-The fiber will be scheduled on the next turn.  During the fiber's
-extent, @var{dynamic-state} will be made current, isolating fluid and
-parameter mutations to this fiber."
+The fiber will be scheduled on the next turn.  @var{thunk} will run
+with a copy of the current dynamic state, isolating fluid and
+parameter mutations to the fiber."
   (let* ((fiber (make-fiber sched #f))
-         (thunk (lambda ()
-                  (with-dynamic-state dynamic-state
-                    (lambda ()
-                      (current-fiber fiber)
-                      (thunk))))))
+         (thunk (let ((dynamic-state (current-dynamic-state)))
+                  (lambda ()
+                    (with-dynamic-state dynamic-state
+                                        (lambda ()
+                                          (current-fiber fiber)
+                                          (thunk)))))))
     (nameset-add! fibers-nameset fiber)
     (schedule-fiber! fiber thunk)))
 
diff --git a/fibers/timers.scm b/fibers/timers.scm
index 15638b0..1ccd088 100644
--- a/fibers/timers.scm
+++ b/fibers/timers.scm
@@ -61,8 +61,7 @@ units.  The operation will succeed with no values."
                              (create-fiber (timer-sched)
                                            (lambda ()
                                              (perform-operation (timer-operation expiry))
-                                             (timer))
-                                           (current-dynamic-state))))))
+                                             (timer)))))))
 
 (define (wait-operation seconds)
   "Make an operation that will succeed with no values when