private:
  llvm::sys::SmartMutex<true> mutex_;
  raw_ostream* os_;
};

PrintPass::PrintPass(raw_ostream* os) {
  if (os) {
    os_ = os;
  } else {
    os_ = &llvm::errs();
  }
}

PrintPass::PrintPass(const PrintPass& other) : PrintPass(other.os_) {}

void PrintPass::runOnOperation() {
  llvm::sys::SmartScopedLock<true> instrumentationLock(mutex_);
  OpPrintingFlags flags =

# define GTEST_DEFINE_STATIC_MUTEX_(mutex) \
    ::testing::internal::MutexBase mutex = { PTHREAD_MUTEX_INITIALIZER, false }

// The Mutex class can only be used for mutexes created at runtime. It
// shares its API with MutexBase otherwise.
class Mutex : public MutexBase {
 public:
  Mutex() {
    GTEST_CHECK_POSIX_SUCCESS_(pthread_mutex_init(&mutex_, NULL));
    has_owner_ = false;
  }

# define GTEST_DEFINE_STATIC_MUTEX_(mutex) \
    ::testing::internal::MutexBase mutex = { PTHREAD_MUTEX_INITIALIZER, false }

// The Mutex class can only be used for mutexes created at runtime. It
// shares its API with MutexBase otherwise.
class Mutex : public MutexBase {
 public:
  Mutex() {
    GTEST_CHECK_POSIX_SUCCESS_(pthread_mutex_init(&mutex_, NULL));
    has_owner_ = false;
  }

    static ExecutableClosureStore* instance = new ExecutableClosureStore;
    return instance;
  }

 private:
  mutex mutex_;
  int64_t key_counter_ TF_GUARDED_BY(mutex_);
  absl::flat_hash_map<KeyT, ExecutableClosure<ExecutableType, ClientType>>
      closures_ TF_GUARDED_BY(mutex_);

  ExecutableClosureStore(const ExecutableClosureStore&) = delete;
  void operator=(const ExecutableClosureStore&) = delete;
};

  void PushGTestTrace(const internal::TraceInfo& trace)
      GTEST_LOCK_EXCLUDED_(mutex_);

  // Pops a trace from the per-thread Google Test trace stack.
  void PopGTestTrace()
      GTEST_LOCK_EXCLUDED_(mutex_);

  // Protects mutable state in *impl_.  This is mutable as some const
  // methods need to lock it too.
  mutable internal::Mutex mutex_;

  // Opaque implementation object.  This field is never changed once

  void PushGTestTrace(const internal::TraceInfo& trace)
      GTEST_LOCK_EXCLUDED_(mutex_);

  // Pops a trace from the per-thread Google Test trace stack.
  void PopGTestTrace()
      GTEST_LOCK_EXCLUDED_(mutex_);

  // Protects mutable state in *impl_.  This is mutable as some const
  // methods need to lock it too.
  mutable internal::Mutex mutex_;

  // Opaque implementation object.  This field is never changed once

}

// MutexAt returns a new Mutex with Path set to the given non-empty path.
func MutexAt(path string) *Mutex {
	if path == "" {
		panic("lockedfile.MutexAt: path must be non-empty")
	}
	return &Mutex{Path: path}
}

func (mu *Mutex) String() string {
	return fmt.Sprintf("lockedfile.Mutex(%s)", mu.Path)
}

// Lock attempts to lock the Mutex.
//
// If successful, Lock returns a non-nil unlock function: it is provided as a

func throw(string)
func fatal(string)

// A Mutex is a mutual exclusion lock.
// The zero value for a Mutex is an unlocked mutex.
//
// A Mutex must not be copied after first use.
//
// In the terminology of [the Go memory model],
// the n'th call to [Mutex.Unlock] “synchronizes before” the m'th call to [Mutex.Lock]
// for any n < m.
// A successful call to [Mutex.TryLock] is equivalent to a call to Lock.

  std::vector<tensorflow::mutex*> mutexes;
  std::vector<int32_t> acquire_order;
  for (auto input : input_ids) {
    tensorflow::Var* var;
    tensorflow::mutex* mutex = GetTrainingVariableMutex(ctx, input, &var);
    if (var) vars.push_back(var);
    // Only lock each mutex once if duplicates exist (n^2 but n is 2 or 3).
    if (std::find(mutexes.begin(), mutexes.end(), mutex) == mutexes.end()) {

func (sys *BucketTargetSys) isOffline(ep *url.URL) bool {
	sys.hMutex.RLock()
	defer sys.hMutex.RUnlock()
	if h, ok := sys.hc[ep.Host]; ok {
		return !h.Online
	}
	go sys.initHC(ep)
	return false
}

// markOffline sets endpoint to offline if network i/o timeout seen.
func (sys *BucketTargetSys) markOffline(ep *url.URL) {
	sys.hMutex.Lock()
	defer sys.hMutex.Unlock()
	if h, ok := sys.hc[ep.Host]; ok {