//      MAXLOG = 8.8029691931113054295988e+01 = log(2**127)
//      MINLOG = -8.872283911167299960540e+01 = log(2**-128)
//
// A rational function is used for |x| < 0.625.  The form
// x + x**3 P(x)/Q(x) of Cody & Waite is employed.
// Otherwise,
//      tanh(x) = sinh(x)/cosh(x) = 1  -  2/(exp(2x) + 1).
//
// ACCURACY:
//
//                      Relative error:
// arithmetic   domain     # trials      peak         rms

 	- the HTTP Server stops listening immediately
	- any new request arriving on a new TCP socket is denied with
      a network error similar to 'connection refused'
    - the HTTP Server waits gracefully for existing requests to complete
      up to '60s' (dictated by ShutdownTimeout)
	- active long running requests will receive a GOAWAY.

T0+70s: HTTPServerStoppedListening:

	wg sync.WaitGroup
	// Once Wait is initiated, all consecutive Done invocation will be
	// rate limited using this rate limiter.
	limiter RateLimiter
	stopCtx context.Context

	mu sync.Mutex
	// wait indicate whether Wait is called, if true,
	// then any Add with positive delta will return error.
	wait bool
	// number of request(s) currently using the wait group
	count int
}

			target.Add(1)
		}()
	}
	wg.Wait()

	waitingCh := make(chan struct{})
	wg.Add(n)
	for i := 0; i < n; i++ {
		go func() {
			defer wg.Done()

			<-waitingCh
			target.Done()
		}()
	}
	defer wg.Wait()

	now := time.Now()
	t.Logf("Wait starting, N=%d, grace: %s, at: %s", n, grace, now)

        and:
        // command the gate keeper to open the gate and shutdown
        command.releaseAll()
        server.expect(server.get("command").send("stop"))
        then:
        // waits for build to start and finish
        buildTriggeredAndSucceeded()
        // Change has been incorporated
        outputFile.text == "changed"
    }

func (fw *filteredWatch) ResultChan() <-chan Event {
	return fw.result
}

// Stop stops the upstream watch, which will eventually stop this watch.
func (fw *filteredWatch) Stop() {
	fw.incoming.Stop()
}

// loop waits for new values, filters them, and resends them.
func (fw *filteredWatch) loop() {
	defer close(fw.result)
	for event := range fw.incoming.ResultChan() {
		filtered, keep := fw.f(event)
		if keep {
			fw.result <- filtered

	c.mutex.Unlock()
	kube.WaitForCacheSync("crd watcher", stop, c.crds.HasSynced)
	c.queue.Run(stop)
	c.crds.ShutdownHandlers()
}

// WaitForCRD waits until the request CRD exists, and returns true on success. A false return value
// indicates the CRD does not exist but the wait failed or was canceled.
// This is useful to conditionally enable controllers based on CRDs being created.

   * necessary. No observable state associated with this cache is modified until loading completes.
   *
   * <p>If another call to {@link #get} or {@link #getUnchecked} is currently loading the value for
   * {@code key}, simply waits for that thread to finish and returns its loaded value. Note that
   * multiple threads can concurrently load values for distinct keys.
   *

			atomic.AddInt32(n, 1)
			wg.Done()
		}()
		// Wait for goroutine 1 and 2
		wg.Wait()
		if atomic.LoadInt32(n) != 2 {
			t.Fatal("Spurious wakeup from Wait")
		}
	}
}

func TestWaitGroupAlign(t *testing.T) {
	type X struct {
		x  byte
		wg WaitGroup
	}
	var x X
	x.wg.Add(1)
	go func(x *X) {
		x.wg.Done()
	}(&x)
	x.wg.Wait()
}

func BenchmarkWaitGroupUncontended(b *testing.B) {

	vlp := (*efaceWords)(unsafe.Pointer(&val))
	for {
		typ := LoadPointer(&vp.typ)
		if typ == nil {
			// Attempt to start first store.
			// Disable preemption so that other goroutines can use
			// active spin wait to wait for completion.
			runtime_procPin()
			if !CompareAndSwapPointer(&vp.typ, nil, unsafe.Pointer(&firstStoreInProgress)) {
				runtime_procUnpin()
				continue
			}
			// Complete first store.