private OverflowAvoidingLockSupport() {}

  static void parkNanos(@CheckForNull Object blocker, long nanos) {
    // Even in the extremely unlikely event that a thread unblocks itself early after only 68 years,
    // this is indistinguishable from a spurious wakeup, which LockSupport allows.
    LockSupport.parkNanos(blocker, min(nanos, MAX_NANOSECONDS_THRESHOLD));
  }

  private OverflowAvoidingLockSupport() {}

  static void parkNanos(@CheckForNull Object blocker, long nanos) {
    // Even in the extremely unlikely event that a thread unblocks itself early after only 68 years,
    // this is indistinguishable from a spurious wakeup, which LockSupport allows.
    LockSupport.parkNanos(blocker, min(nanos, MAX_NANOSECONDS_THRESHOLD));
  }

	// Call Add(-1) just before waiting on something from another goroutine (e.g.,
	// just before a `select`).
	// Call Add(1) just before doing something that unblocks a goroutine that is
	// waiting on that something.
	Add(delta int)

// license that can be found in the LICENSE file.

// Tests to make sure the runtime doesn't generate futile wakeups. For example,
// it makes sure that a block on a channel send that unblocks briefly only to
// immediately go back to sleep (in such a way that doesn't reveal any useful
// information, and is purely an artifact of the runtime implementation) doesn't
// make it into the trace.

//go:build ignore

// for the Go execution tracer.
//
// # Tracing runtime activities
//
// The execution trace captures a wide range of execution events such as
// goroutine creation/blocking/unblocking, syscall enter/exit/block,
// GC-related events, changes of heap size, processor start/stop, etc.
// When CPU profiling is active, the execution tracer makes an effort to
// include those samples as well.

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutionException;

/**
 * Asynchronously cleans up the VFS after a build.
 *
 * Unblocks the client to receive the build finished event while the cleanup is happening.
 * However, the next build is not allowed to start until the cleanup is finished.
 */
@NonNullApi

				ret = mapErr(ctxErr)
				fd.Close() // prevent a leak
			}
		}()
		go func() {
			select {
			case <-ctxDone:
				// Force the runtime's poller to immediately give up
				// waiting for writability, unblocking waitWrite
				// below.
				fd.pfd.SetWriteDeadline(aLongTimeAgo)
				testHookCanceledDial()
				interruptRes <- ctx.Err()
			case <-done:
				interruptRes <- nil
			}
		}()
	}

	for {

			t.Error(blerr)
			return
		}
		locked <- struct{}{}
		if blerr = bl.Close(); blerr != nil {
			t.Error(blerr)
			return
		}
	}()

	select {
	case <-locked:
		t.Error("unexpected unblocking")
	case <-time.After(100 * time.Millisecond):
	}

	// unlock
	if err = dupl.Close(); err != nil {
		t.Fatal(err)
	}

	// the previously blocked routine should be unblocked
	select {

//
// A Cond must not be copied after first use.
//
// In the terminology of [the Go memory model], Cond arranges that
// a call to [Cond.Broadcast] or [Cond.Signal] “synchronizes before” any Wait call
// that it unblocks.
//
// For many simple use cases, users will be better off using channels than a
// Cond (Broadcast corresponds to closing a channel, and Signal corresponds to
// sending on a channel).
//

//
// A WaitGroup must not be copied after first use.
//
// In the terminology of [the Go memory model], a call to [WaitGroup.Done]
// “synchronizes before” the return of any Wait call that it unblocks.
//
// [the Go memory model]: https://go.dev/ref/mem
type WaitGroup struct {
	noCopy noCopy

	state atomic.Uint64 // high 32 bits are counter, low 32 bits are waiter count.
	sema  uint32
}