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verified gcc-4.6.4.tar.bz2.sig;
imported gcc-4.6.4 source tree from verified upstream tarball.

downloading a git-generated archive based on the 'upstream' tag
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1 files changed, 830 insertions, 0 deletions

diff --git a/libstdc++-v3/include/std/mutex b/libstdc++-v3/include/std/mutex
new file mode 100644
index 000000000..ed530e4f0
--- /dev/null
+++ b/libstdc++-v3/include/std/mutex
@@ -0,0 +1,830 @@
+// <mutex> -*- C++ -*-
+
+// Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
+// Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// Under Section 7 of GPL version 3, you are granted additional
+// permissions described in the GCC Runtime Library Exception, version
+// 3.1, as published by the Free Software Foundation.
+
+// You should have received a copy of the GNU General Public License and
+// a copy of the GCC Runtime Library Exception along with this program;
+// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+// <http://www.gnu.org/licenses/>.
+
+/** @file include/mutex
+ *  This is a Standard C++ Library header.
+ */
+
+#ifndef _GLIBCXX_MUTEX
+#define _GLIBCXX_MUTEX 1
+
+#pragma GCC system_header
+
+#ifndef __GXX_EXPERIMENTAL_CXX0X__
+# include <bits/c++0x_warning.h>
+#else
+
+#include <tuple>
+#include <chrono>
+#include <exception>
+#include <type_traits>
+#include <functional>
+#include <system_error>
+#include <bits/functexcept.h>
+#include <bits/gthr.h>
+#include <bits/move.h> // for std::swap
+
+#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
+
+namespace std _GLIBCXX_VISIBILITY(default)
+{
+_GLIBCXX_BEGIN_NAMESPACE_VERSION
+
+  /**
+   * @defgroup mutexes Mutexes
+   * @ingroup concurrency
+   *
+   * Classes for mutex support.
+   * @{
+   */
+
+  /// mutex
+  class mutex
+  {
+    typedef __gthread_mutex_t			__native_type;
+    __native_type  _M_mutex;
+
+  public:
+    typedef __native_type* 			native_handle_type;
+
+#ifdef __GTHREAD_MUTEX_INIT
+    constexpr mutex() : _M_mutex(__GTHREAD_MUTEX_INIT) { }
+#else
+    mutex()
+    {
+      // XXX EAGAIN, ENOMEM, EPERM, EBUSY(may), EINVAL(may)
+      __GTHREAD_MUTEX_INIT_FUNCTION(&_M_mutex);
+    }
+
+    ~mutex() { __gthread_mutex_destroy(&_M_mutex); }
+#endif
+
+    mutex(const mutex&) = delete;
+    mutex& operator=(const mutex&) = delete;
+
+    void
+    lock()
+    {
+      int __e = __gthread_mutex_lock(&_M_mutex);
+
+      // EINVAL, EAGAIN, EBUSY, EINVAL, EDEADLK(may)
+      if (__e)
+	__throw_system_error(__e);
+    }
+
+    bool
+    try_lock()
+    {
+      // XXX EINVAL, EAGAIN, EBUSY
+      return !__gthread_mutex_trylock(&_M_mutex);
+    }
+
+    void
+    unlock()
+    {
+      // XXX EINVAL, EAGAIN, EPERM
+      __gthread_mutex_unlock(&_M_mutex);
+    }
+
+    native_handle_type
+    native_handle()
+    { return &_M_mutex; }
+  };
+
+#ifndef __GTHREAD_RECURSIVE_MUTEX_INIT
+  // FIXME: gthreads doesn't define __gthread_recursive_mutex_destroy
+  // so we need to obtain a __gthread_mutex_t to destroy
+  class __destroy_recursive_mutex
+  {
+    template<typename _Mx, typename _Rm>
+      static void
+      _S_destroy_win32(_Mx* __mx, _Rm const* __rmx)
+      {
+        __mx->counter = __rmx->counter;
+        __mx->sema = __rmx->sema;
+        __gthread_mutex_destroy(__mx);
+      }
+
+  public:
+    // matches a gthr-win32.h recursive mutex
+    template<typename _Rm>
+      static typename enable_if<(bool)sizeof(&_Rm::sema), void>::type
+      _S_destroy(_Rm* __mx)
+      {
+        __gthread_mutex_t __tmp;
+        _S_destroy_win32(&__tmp, __mx);
+      }
+
+    // matches a recursive mutex with a member 'actual'
+    template<typename _Rm>
+      static typename enable_if<(bool)sizeof(&_Rm::actual), void>::type
+      _S_destroy(_Rm* __mx)
+      { __gthread_mutex_destroy(&__mx->actual); }
+
+    // matches when there's only one mutex type
+    template<typename _Rm>
+      static
+      typename enable_if<is_same<_Rm, __gthread_mutex_t>::value, void>::type
+      _S_destroy(_Rm* __mx)
+      { __gthread_mutex_destroy(__mx); }
+  };
+#endif
+
+  /// recursive_mutex
+  class recursive_mutex
+  {
+    typedef __gthread_recursive_mutex_t		__native_type;
+    __native_type  _M_mutex;
+
+  public:
+    typedef __native_type* 			native_handle_type;
+
+#ifdef __GTHREAD_RECURSIVE_MUTEX_INIT
+    recursive_mutex() : _M_mutex(__GTHREAD_RECURSIVE_MUTEX_INIT) { }
+#else
+    recursive_mutex()
+    {
+      // XXX EAGAIN, ENOMEM, EPERM, EBUSY(may), EINVAL(may)
+      __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION(&_M_mutex);
+    }
+
+    ~recursive_mutex()
+    { __destroy_recursive_mutex::_S_destroy(&_M_mutex); }
+#endif
+
+    recursive_mutex(const recursive_mutex&) = delete;
+    recursive_mutex& operator=(const recursive_mutex&) = delete;
+
+    void
+    lock()
+    {
+      int __e = __gthread_recursive_mutex_lock(&_M_mutex);
+
+      // EINVAL, EAGAIN, EBUSY, EINVAL, EDEADLK(may)
+      if (__e)
+	__throw_system_error(__e);
+    }
+
+    bool
+    try_lock()
+    {
+      // XXX EINVAL, EAGAIN, EBUSY
+      return !__gthread_recursive_mutex_trylock(&_M_mutex);
+    }
+
+    void
+    unlock()
+    {
+      // XXX EINVAL, EAGAIN, EBUSY
+      __gthread_recursive_mutex_unlock(&_M_mutex);
+    }
+
+    native_handle_type
+    native_handle()
+    { return &_M_mutex; }
+  };
+
+  /// timed_mutex
+  class timed_mutex
+  {
+    typedef __gthread_mutex_t 		  	__native_type;
+
+#ifdef _GLIBCXX_USE_CLOCK_MONOTONIC
+    typedef chrono::monotonic_clock 	  	__clock_t;
+#else
+    typedef chrono::high_resolution_clock 	__clock_t;
+#endif
+
+    __native_type  _M_mutex;
+
+  public:
+    typedef __native_type* 		  	native_handle_type;
+
+#ifdef __GTHREAD_MUTEX_INIT
+    timed_mutex() : _M_mutex(__GTHREAD_MUTEX_INIT) { }
+#else
+    timed_mutex()
+    {
+      __GTHREAD_MUTEX_INIT_FUNCTION(&_M_mutex);
+    }
+
+    ~timed_mutex() { __gthread_mutex_destroy(&_M_mutex); }
+#endif
+
+    timed_mutex(const timed_mutex&) = delete;
+    timed_mutex& operator=(const timed_mutex&) = delete;
+
+    void
+    lock()
+    {
+      int __e = __gthread_mutex_lock(&_M_mutex);
+
+      // EINVAL, EAGAIN, EBUSY, EINVAL, EDEADLK(may)
+      if (__e)
+	__throw_system_error(__e);
+    }
+
+    bool
+    try_lock()
+    {
+      // XXX EINVAL, EAGAIN, EBUSY
+      return !__gthread_mutex_trylock(&_M_mutex);
+    }
+
+    template <class _Rep, class _Period>
+      bool
+      try_lock_for(const chrono::duration<_Rep, _Period>& __rtime)
+      { return __try_lock_for_impl(__rtime); }
+
+    template <class _Clock, class _Duration>
+      bool
+      try_lock_until(const chrono::time_point<_Clock, _Duration>& __atime)
+      {
+	chrono::time_point<_Clock, chrono::seconds> __s =
+	  chrono::time_point_cast<chrono::seconds>(__atime);
+
+	chrono::nanoseconds __ns =
+	  chrono::duration_cast<chrono::nanoseconds>(__atime - __s);
+
+	__gthread_time_t __ts = {
+	  static_cast<std::time_t>(__s.time_since_epoch().count()),
+	  static_cast<long>(__ns.count())
+	};
+
+	return !__gthread_mutex_timedlock(&_M_mutex, &__ts);
+      }
+
+    void
+    unlock()
+    {
+      // XXX EINVAL, EAGAIN, EBUSY
+      __gthread_mutex_unlock(&_M_mutex);
+    }
+
+    native_handle_type
+    native_handle()
+    { return &_M_mutex; }
+
+  private:
+    template<typename _Rep, typename _Period>
+      typename enable_if<
+	ratio_less_equal<__clock_t::period, _Period>::value, bool>::type
+      __try_lock_for_impl(const chrono::duration<_Rep, _Period>& __rtime)
+      {
+	__clock_t::time_point __atime = __clock_t::now()
+	  + chrono::duration_cast<__clock_t::duration>(__rtime);
+
+	return try_lock_until(__atime);
+      }
+
+    template <typename _Rep, typename _Period>
+      typename enable_if<
+	!ratio_less_equal<__clock_t::period, _Period>::value, bool>::type
+      __try_lock_for_impl(const chrono::duration<_Rep, _Period>& __rtime)
+      {
+	__clock_t::time_point __atime = __clock_t::now()
+	  + ++chrono::duration_cast<__clock_t::duration>(__rtime);
+
+	return try_lock_until(__atime);
+      }
+  };
+
+  /// recursive_timed_mutex
+  class recursive_timed_mutex
+  {
+    typedef __gthread_recursive_mutex_t		__native_type;
+
+#ifdef _GLIBCXX_USE_CLOCK_MONOTONIC
+    typedef chrono::monotonic_clock 		__clock_t;
+#else
+    typedef chrono::high_resolution_clock 	__clock_t;
+#endif
+
+    __native_type  _M_mutex;
+
+  public:
+    typedef __native_type* 			native_handle_type;
+
+#ifdef __GTHREAD_RECURSIVE_MUTEX_INIT
+    recursive_timed_mutex() : _M_mutex(__GTHREAD_RECURSIVE_MUTEX_INIT) { }
+#else
+    recursive_timed_mutex()
+    {
+      // XXX EAGAIN, ENOMEM, EPERM, EBUSY(may), EINVAL(may)
+      __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION(&_M_mutex);
+    }
+
+    ~recursive_timed_mutex()
+    { __destroy_recursive_mutex::_S_destroy(&_M_mutex); }
+#endif
+
+    recursive_timed_mutex(const recursive_timed_mutex&) = delete;
+    recursive_timed_mutex& operator=(const recursive_timed_mutex&) = delete;
+
+    void
+    lock()
+    {
+      int __e = __gthread_recursive_mutex_lock(&_M_mutex);
+
+      // EINVAL, EAGAIN, EBUSY, EINVAL, EDEADLK(may)
+      if (__e)
+	__throw_system_error(__e);
+    }
+
+    bool
+    try_lock()
+    {
+      // XXX EINVAL, EAGAIN, EBUSY
+      return !__gthread_recursive_mutex_trylock(&_M_mutex);
+    }
+
+    template <class _Rep, class _Period>
+      bool
+      try_lock_for(const chrono::duration<_Rep, _Period>& __rtime)
+      { return __try_lock_for_impl(__rtime); }
+
+    template <class _Clock, class _Duration>
+      bool
+      try_lock_until(const chrono::time_point<_Clock, _Duration>& __atime)
+      {
+	chrono::time_point<_Clock, chrono::seconds>  __s =
+	  chrono::time_point_cast<chrono::seconds>(__atime);
+
+	chrono::nanoseconds __ns =
+	  chrono::duration_cast<chrono::nanoseconds>(__atime - __s);
+
+	__gthread_time_t __ts = {
+	  static_cast<std::time_t>(__s.time_since_epoch().count()),
+	  static_cast<long>(__ns.count())
+	};
+
+	return !__gthread_recursive_mutex_timedlock(&_M_mutex, &__ts);
+      }
+
+    void
+    unlock()
+    {
+      // XXX EINVAL, EAGAIN, EBUSY
+      __gthread_recursive_mutex_unlock(&_M_mutex);
+    }
+
+    native_handle_type
+    native_handle()
+    { return &_M_mutex; }
+
+  private:
+    template<typename _Rep, typename _Period>
+      typename enable_if<
+	ratio_less_equal<__clock_t::period, _Period>::value, bool>::type
+      __try_lock_for_impl(const chrono::duration<_Rep, _Period>& __rtime)
+      {
+	__clock_t::time_point __atime = __clock_t::now()
+	  + chrono::duration_cast<__clock_t::duration>(__rtime);
+
+	return try_lock_until(__atime);
+      }
+
+    template <typename _Rep, typename _Period>
+      typename enable_if<
+	!ratio_less_equal<__clock_t::period, _Period>::value, bool>::type
+      __try_lock_for_impl(const chrono::duration<_Rep, _Period>& __rtime)
+      {
+	__clock_t::time_point __atime = __clock_t::now()
+	  + ++chrono::duration_cast<__clock_t::duration>(__rtime);
+
+	return try_lock_until(__atime);
+      }
+  };
+
+  /// Do not acquire ownership of the mutex.
+  struct defer_lock_t { };
+
+  /// Try to acquire ownership of the mutex without blocking.
+  struct try_to_lock_t { };
+
+  /// Assume the calling thread has already obtained mutex ownership
+  /// and manage it.
+  struct adopt_lock_t { };
+
+  constexpr defer_lock_t	defer_lock { };
+  constexpr try_to_lock_t	try_to_lock { };
+  constexpr adopt_lock_t	adopt_lock { };
+
+  /// @brief  Scoped lock idiom.
+  // Acquire the mutex here with a constructor call, then release with
+  // the destructor call in accordance with RAII style.
+  template<typename _Mutex>
+    class lock_guard
+    {
+    public:
+      typedef _Mutex mutex_type;
+
+      explicit lock_guard(mutex_type& __m) : _M_device(__m)
+      { _M_device.lock(); }
+
+      lock_guard(mutex_type& __m, adopt_lock_t) : _M_device(__m)
+      { } // calling thread owns mutex
+
+      ~lock_guard()
+      { _M_device.unlock(); }
+
+      lock_guard(const lock_guard&) = delete;
+      lock_guard& operator=(const lock_guard&) = delete;
+
+    private:
+      mutex_type&  _M_device;
+    };
+
+  /// unique_lock
+  template<typename _Mutex>
+    class unique_lock
+    {
+    public:
+      typedef _Mutex mutex_type;
+
+      unique_lock()
+      : _M_device(0), _M_owns(false)
+      { }
+
+      explicit unique_lock(mutex_type& __m)
+      : _M_device(&__m), _M_owns(false)
+      {
+	lock();
+	_M_owns = true;
+      }
+
+      unique_lock(mutex_type& __m, defer_lock_t)
+      : _M_device(&__m), _M_owns(false)
+      { }
+
+      unique_lock(mutex_type& __m, try_to_lock_t)
+      : _M_device(&__m), _M_owns(_M_device->try_lock())
+      { }
+
+      unique_lock(mutex_type& __m, adopt_lock_t)
+      : _M_device(&__m), _M_owns(true)
+      {
+	// XXX calling thread owns mutex
+      }
+
+      template<typename _Clock, typename _Duration>
+	unique_lock(mutex_type& __m,
+		    const chrono::time_point<_Clock, _Duration>& __atime)
+	: _M_device(&__m), _M_owns(_M_device->try_lock_until(__atime))
+	{ }
+
+      template<typename _Rep, typename _Period>
+	unique_lock(mutex_type& __m,
+		    const chrono::duration<_Rep, _Period>& __rtime)
+	: _M_device(&__m), _M_owns(_M_device->try_lock_for(__rtime))
+	{ }
+
+      ~unique_lock()
+      {
+	if (_M_owns)
+	  unlock();
+      }
+
+      unique_lock(const unique_lock&) = delete;
+      unique_lock& operator=(const unique_lock&) = delete;
+
+      unique_lock(unique_lock&& __u)
+      : _M_device(__u._M_device), _M_owns(__u._M_owns)
+      {
+	__u._M_device = 0;
+	__u._M_owns = false;
+      }
+
+      unique_lock& operator=(unique_lock&& __u)
+      {
+	if(_M_owns)
+	  unlock();
+
+	unique_lock(std::move(__u)).swap(*this);
+
+	__u._M_device = 0;
+	__u._M_owns = false;
+
+	return *this;
+      }
+
+      void
+      lock()
+      {
+	if (!_M_device)
+	  __throw_system_error(int(errc::operation_not_permitted));
+	else if (_M_owns)
+	  __throw_system_error(int(errc::resource_deadlock_would_occur));
+	else
+	  {
+	    _M_device->lock();
+	    _M_owns = true;
+	  }
+      }
+
+      bool
+      try_lock()
+      {
+	if (!_M_device)
+	  __throw_system_error(int(errc::operation_not_permitted));
+	else if (_M_owns)
+	  __throw_system_error(int(errc::resource_deadlock_would_occur));
+	else
+	  {
+	    _M_owns = _M_device->try_lock();
+	    return _M_owns;
+	  }
+      }
+
+      template<typename _Clock, typename _Duration>
+	bool
+	try_lock_until(const chrono::time_point<_Clock, _Duration>& __atime)
+	{
+	  if (!_M_device)
+	    __throw_system_error(int(errc::operation_not_permitted));
+	  else if (_M_owns)
+	    __throw_system_error(int(errc::resource_deadlock_would_occur));
+	  else
+	    {
+	      _M_owns = _M_device->try_lock_until(__atime);
+	      return _M_owns;
+	    }
+	}
+
+      template<typename _Rep, typename _Period>
+	bool
+	try_lock_for(const chrono::duration<_Rep, _Period>& __rtime)
+	{
+	  if (!_M_device)
+	    __throw_system_error(int(errc::operation_not_permitted));
+	  else if (_M_owns)
+	    __throw_system_error(int(errc::resource_deadlock_would_occur));
+	  else
+	    {
+	      _M_owns = _M_device->try_lock_for(__rtime);
+	      return _M_owns;
+	    }
+	 }
+
+      void
+      unlock()
+      {
+	if (!_M_owns)
+	  __throw_system_error(int(errc::operation_not_permitted));
+	else if (_M_device)
+	  {
+	    _M_device->unlock();
+	    _M_owns = false;
+	  }
+      }
+
+      void
+      swap(unique_lock& __u)
+      {
+	std::swap(_M_device, __u._M_device);
+	std::swap(_M_owns, __u._M_owns);
+      }
+
+      mutex_type*
+      release()
+      {
+	mutex_type* __ret = _M_device;
+	_M_device = 0;
+	_M_owns = false;
+	return __ret;
+      }
+
+      bool
+      owns_lock() const
+      { return _M_owns; }
+
+      explicit operator bool() const
+      { return owns_lock(); }
+
+      mutex_type*
+      mutex() const
+      { return _M_device; }
+
+    private:
+      mutex_type*	_M_device;
+      bool		_M_owns; // XXX use atomic_bool
+    };
+
+  template<typename _Mutex>
+    inline void
+    swap(unique_lock<_Mutex>& __x, unique_lock<_Mutex>& __y)
+    { __x.swap(__y); }
+
+  template<int _Idx>
+    struct __unlock_impl
+    {
+      template<typename... _Lock>
+	static void
+	__do_unlock(tuple<_Lock&...>& __locks)
+	{
+	  std::get<_Idx>(__locks).unlock();
+	  __unlock_impl<_Idx - 1>::__do_unlock(__locks);
+	}
+    };
+
+  template<>
+    struct __unlock_impl<-1>
+    {
+      template<typename... _Lock>
+	static void
+	__do_unlock(tuple<_Lock&...>&)
+	{ }
+    };
+
+  template<typename _Lock>
+    unique_lock<_Lock>
+    __try_to_lock(_Lock& __l)
+    { return unique_lock<_Lock>(__l, try_to_lock); }
+
+  template<int _Idx, bool _Continue = true>
+    struct __try_lock_impl
+    {
+      template<typename... _Lock>
+	static void
+	__do_try_lock(tuple<_Lock&...>& __locks, int& __idx)
+	{
+          __idx = _Idx;
+          auto __lock = __try_to_lock(std::get<_Idx>(__locks));
+          if (__lock.owns_lock())
+            {
+              __try_lock_impl<_Idx + 1, _Idx + 2 < sizeof...(_Lock)>::
+                __do_try_lock(__locks, __idx);
+              if (__idx == -1)
+                __lock.release();
+            }
+	}
+    };
+
+  template<int _Idx>
+    struct __try_lock_impl<_Idx, false>
+    {
+      template<typename... _Lock>
+	static void
+	__do_try_lock(tuple<_Lock&...>& __locks, int& __idx)
+	{
+          __idx = _Idx;
+          auto __lock = __try_to_lock(std::get<_Idx>(__locks));
+          if (__lock.owns_lock())
+            {
+              __idx = -1;
+              __lock.release();
+            }
+	}
+    };
+
+  /** @brief Generic try_lock.
+   *  @param __l1 Meets Mutex requirements (try_lock() may throw).
+   *  @param __l2 Meets Mutex requirements (try_lock() may throw).
+   *  @param __l3 Meets Mutex requirements (try_lock() may throw).
+   *  @return Returns -1 if all try_lock() calls return true. Otherwise returns
+   *          a 0-based index corresponding to the argument that returned false.
+   *  @post Either all arguments are locked, or none will be.
+   *
+   *  Sequentially calls try_lock() on each argument.
+   */
+  template<typename _Lock1, typename _Lock2, typename... _Lock3>
+    int
+    try_lock(_Lock1& __l1, _Lock2& __l2, _Lock3&... __l3)
+    {
+      int __idx;
+      auto __locks = std::tie(__l1, __l2, __l3...);
+      __try
+      { __try_lock_impl<0>::__do_try_lock(__locks, __idx); }
+      __catch(...)
+      { }
+      return __idx;
+    }
+
+  /** @brief Generic lock.
+   *  @param __l1 Meets Mutex requirements (try_lock() may throw).
+   *  @param __l2 Meets Mutex requirements (try_lock() may throw).
+   *  @param __l3 Meets Mutex requirements (try_lock() may throw).
+   *  @throw An exception thrown by an argument's lock() or try_lock() member.
+   *  @post All arguments are locked.
+   *
+   *  All arguments are locked via a sequence of calls to lock(), try_lock()
+   *  and unlock().  If the call exits via an exception any locks that were
+   *  obtained will be released.
+   */
+  template<typename _L1, typename _L2, typename ..._L3>
+    void
+    lock(_L1& __l1, _L2& __l2, _L3&... __l3)
+    {
+      while (true)
+        {
+          unique_lock<_L1> __first(__l1);
+          int __idx;
+          auto __locks = std::tie(__l2, __l3...);
+          __try_lock_impl<0, sizeof...(_L3)>::__do_try_lock(__locks, __idx);
+          if (__idx == -1)
+            {
+              __first.release();
+              return;
+            }
+        }
+    }
+
+  /// once_flag
+  struct once_flag
+  {
+  private:
+    typedef __gthread_once_t __native_type;
+    __native_type  _M_once;
+
+  public:
+    constexpr once_flag() : _M_once(__GTHREAD_ONCE_INIT) { }
+
+    once_flag(const once_flag&) = delete;
+    once_flag& operator=(const once_flag&) = delete;
+
+    template<typename _Callable, typename... _Args>
+      friend void
+      call_once(once_flag& __once, _Callable&& __f, _Args&&... __args);
+  };
+
+#ifdef _GLIBCXX_HAVE_TLS
+  extern __thread void* __once_callable;
+  extern __thread void (*__once_call)();
+
+  template<typename _Callable>
+    inline void
+    __once_call_impl()
+    {
+      (*(_Callable*)__once_callable)();
+    }
+#else
+  extern function<void()> __once_functor;
+
+  extern void
+  __set_once_functor_lock_ptr(unique_lock<mutex>*);
+
+  extern mutex&
+  __get_once_mutex();
+#endif
+
+  extern "C" void __once_proxy();
+
+  /// call_once
+  template<typename _Callable, typename... _Args>
+    void
+    call_once(once_flag& __once, _Callable&& __f, _Args&&... __args)
+    {
+#ifdef _GLIBCXX_HAVE_TLS
+      auto __bound_functor = std::bind<void>(std::forward<_Callable>(__f),
+          std::forward<_Args>(__args)...);
+      __once_callable = &__bound_functor;
+      __once_call = &__once_call_impl<decltype(__bound_functor)>;
+#else
+      unique_lock<mutex> __functor_lock(__get_once_mutex());
+      __once_functor = std::bind<void>(std::forward<_Callable>(__f),
+          std::forward<_Args>(__args)...);
+      __set_once_functor_lock_ptr(&__functor_lock);
+#endif
+
+      int __e = __gthread_once(&(__once._M_once), &__once_proxy);
+
+#ifndef _GLIBCXX_HAVE_TLS
+      if (__functor_lock)
+        __set_once_functor_lock_ptr(0);
+#endif
+
+      if (__e)
+	__throw_system_error(__e);
+    }
+
+  // @} group mutexes
+_GLIBCXX_END_NAMESPACE_VERSION
+} // namespace
+
+#endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1
+
+#endif // __GXX_EXPERIMENTAL_CXX0X__
+
+#endif // _GLIBCXX_MUTEX