Avoid missed wakeup with fiber scheduler and Fiber.blocking. (#6588)

* Ensure that blocked fibers don't prevent valid wakeups.

1 files changed, 2 insertions, 2 deletions

diff --git a/thread.c b/thread.c
index e1b194861a..d8925e618e 100644
--- a/thread.c
+++ b/thread.c
@@ -404,7 +404,7 @@ rb_threadptr_join_list_wakeup(rb_thread_t *thread)
 
         rb_thread_t *target_thread = join_list->thread;
 
-        if (target_thread->scheduler != Qnil && rb_fiberptr_blocking(join_list->fiber) == 0) {
+        if (target_thread->scheduler != Qnil && join_list->fiber) {
             rb_fiber_scheduler_unblock(target_thread->scheduler, target_thread->self, rb_fiberptr_self(join_list->fiber));
         }
         else {
@@ -1091,7 +1091,7 @@ thread_join(rb_thread_t *target_th, VALUE timeout, rb_hrtime_t *limit)
         struct rb_waiting_list waiter;
         waiter.next = target_th->join_list;
         waiter.thread = th;
-        waiter.fiber = fiber;
+        waiter.fiber = rb_fiberptr_blocking(fiber) ? NULL : fiber;
         target_th->join_list = &waiter;
 
         struct join_arg arg;