// -*- C++ -*- header.
	
	// Copyright (C) 2008-2013 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 bits/atomic_base.h
	 *  This is an internal header file, included by other library headers.
	 *  Do not attempt to use it directly. @headername{atomic}
	 */
	
	#ifndef _GLIBCXX_ATOMIC_BASE_H
	#define _GLIBCXX_ATOMIC_BASE_H 1
	
	#pragma GCC system_header
	
	#include <bits/c++config.h>
	#include <stdbool.h>
	#include <stdint.h>
	#include <bits/atomic_lockfree_defines.h>
	
	namespace std _GLIBCXX_VISIBILITY(default)
	{
	_GLIBCXX_BEGIN_NAMESPACE_VERSION
	
	  /**
	   * @defgroup atomics Atomics
	   *
	   * Components for performing atomic operations.
	   * @{
	   */
	
	  /// Enumeration for memory_order
	  typedef enum memory_order
	    {
	      memory_order_relaxed,
	      memory_order_consume,
	      memory_order_acquire,
	      memory_order_release,
	      memory_order_acq_rel,
	      memory_order_seq_cst
	    } memory_order;
	
	  enum __memory_order_modifier
	    {
	      __memory_order_mask          = 0x0ffff,
	      __memory_order_modifier_mask = 0xffff0000,
	      __memory_order_hle_acquire   = 0x10000,
	      __memory_order_hle_release   = 0x20000
	    };
	
	  constexpr memory_order
	  operator|(memory_order __m, __memory_order_modifier __mod)
	  {
	    return memory_order(__m | int(__mod));
	  }
	
	  constexpr memory_order
	  operator&(memory_order __m, __memory_order_modifier __mod)
	  {
	    return memory_order(__m & int(__mod));
	  }
	
	  // Drop release ordering as per [atomics.types.operations.req]/21
	  constexpr memory_order
	  __cmpexch_failure_order2(memory_order __m) noexcept
	  {
	    return __m == memory_order_acq_rel ? memory_order_acquire
	      : __m == memory_order_release ? memory_order_relaxed : __m;
	  }
	
	  constexpr memory_order
	  __cmpexch_failure_order(memory_order __m) noexcept
	  {
	    return memory_order(__cmpexch_failure_order2(__m & __memory_order_mask)
	      | (__m & __memory_order_modifier_mask));
	  }
	
	  inline void
	  atomic_thread_fence(memory_order __m) noexcept
	  { __atomic_thread_fence(__m); }
	
	  inline void
	  atomic_signal_fence(memory_order __m) noexcept
	  { __atomic_signal_fence(__m); }
	
	  /// kill_dependency
	  template<typename _Tp>
	    inline _Tp
	    kill_dependency(_Tp __y) noexcept
	    {
	      _Tp __ret(__y);
	      return __ret;
	    }
	
	
	  // Base types for atomics.
	  template<typename _IntTp>
	    struct __atomic_base;
	
	  /// atomic_char
	  typedef __atomic_base<char>  	       		atomic_char;
	
	  /// atomic_schar
	  typedef __atomic_base<signed char>	     	atomic_schar;
	
	  /// atomic_uchar
	  typedef __atomic_base<unsigned char>		atomic_uchar;
	
	  /// atomic_short
	  typedef __atomic_base<short>			atomic_short;
	
	  /// atomic_ushort
	  typedef __atomic_base<unsigned short>	 	atomic_ushort;
	
	  /// atomic_int
	  typedef __atomic_base<int>  	       		atomic_int;
	
	  /// atomic_uint
	  typedef __atomic_base<unsigned int>	     	atomic_uint;
	
	  /// atomic_long
	  typedef __atomic_base<long>  	       		atomic_long;
	
	  /// atomic_ulong
	  typedef __atomic_base<unsigned long>		atomic_ulong;
	
	  /// atomic_llong
	  typedef __atomic_base<long long>  		atomic_llong;
	
	  /// atomic_ullong
	  typedef __atomic_base<unsigned long long> 	atomic_ullong;
	
	  /// atomic_wchar_t
	  typedef __atomic_base<wchar_t>  		atomic_wchar_t;
	
	  /// atomic_char16_t
	  typedef __atomic_base<char16_t>  		atomic_char16_t;
	
	  /// atomic_char32_t
	  typedef __atomic_base<char32_t>  		atomic_char32_t;
	
	  /// atomic_char32_t
	  typedef __atomic_base<char32_t>  		atomic_char32_t;
	
	
	  /// atomic_int_least8_t
	  typedef __atomic_base<int_least8_t>  		atomic_int_least8_t;
	
	  /// atomic_uint_least8_t
	  typedef __atomic_base<uint_least8_t>	       	atomic_uint_least8_t;
	
	  /// atomic_int_least16_t
	  typedef __atomic_base<int_least16_t>	       	atomic_int_least16_t;
	
	  /// atomic_uint_least16_t
	  typedef __atomic_base<uint_least16_t>	       	atomic_uint_least16_t;
	
	  /// atomic_int_least32_t
	  typedef __atomic_base<int_least32_t>	       	atomic_int_least32_t;
	
	  /// atomic_uint_least32_t
	  typedef __atomic_base<uint_least32_t>	       	atomic_uint_least32_t;
	
	  /// atomic_int_least64_t
	  typedef __atomic_base<int_least64_t>	       	atomic_int_least64_t;
	
	  /// atomic_uint_least64_t
	  typedef __atomic_base<uint_least64_t>	       	atomic_uint_least64_t;
	
	
	  /// atomic_int_fast8_t
	  typedef __atomic_base<int_fast8_t>  		atomic_int_fast8_t;
	
	  /// atomic_uint_fast8_t
	  typedef __atomic_base<uint_fast8_t>	      	atomic_uint_fast8_t;
	
	  /// atomic_int_fast16_t
	  typedef __atomic_base<int_fast16_t>	      	atomic_int_fast16_t;
	
	  /// atomic_uint_fast16_t
	  typedef __atomic_base<uint_fast16_t>	      	atomic_uint_fast16_t;
	
	  /// atomic_int_fast32_t
	  typedef __atomic_base<int_fast32_t>	      	atomic_int_fast32_t;
	
	  /// atomic_uint_fast32_t
	  typedef __atomic_base<uint_fast32_t>	      	atomic_uint_fast32_t;
	
	  /// atomic_int_fast64_t
	  typedef __atomic_base<int_fast64_t>	      	atomic_int_fast64_t;
	
	  /// atomic_uint_fast64_t
	  typedef __atomic_base<uint_fast64_t>	      	atomic_uint_fast64_t;
	
	
	  /// atomic_intptr_t
	  typedef __atomic_base<intptr_t>  	       	atomic_intptr_t;
	
	  /// atomic_uintptr_t
	  typedef __atomic_base<uintptr_t>  	       	atomic_uintptr_t;
	
	  /// atomic_size_t
	  typedef __atomic_base<size_t>	 	       	atomic_size_t;
	
	  /// atomic_intmax_t
	  typedef __atomic_base<intmax_t>  	       	atomic_intmax_t;
	
	  /// atomic_uintmax_t
	  typedef __atomic_base<uintmax_t>  	       	atomic_uintmax_t;
	
	  /// atomic_ptrdiff_t
	  typedef __atomic_base<ptrdiff_t>  	       	atomic_ptrdiff_t;
	
	
	#define ATOMIC_VAR_INIT(_VI) { _VI }
	
	  template<typename _Tp>
	    struct atomic;
	
	  template<typename _Tp>
	    struct atomic<_Tp*>;
	
	    /* The target's "set" value for test-and-set may not be exactly 1.  */
	#if __GCC_ATOMIC_TEST_AND_SET_TRUEVAL == 1
	    typedef bool __atomic_flag_data_type;
	#else
	    typedef unsigned char __atomic_flag_data_type;
	#endif
	
	  /**
	   *  @brief Base type for atomic_flag.
	   *
	   *  Base type is POD with data, allowing atomic_flag to derive from
	   *  it and meet the standard layout type requirement. In addition to
	   *  compatibilty with a C interface, this allows different
	   *  implementations of atomic_flag to use the same atomic operation
	   *  functions, via a standard conversion to the __atomic_flag_base
	   *  argument.
	  */
	  _GLIBCXX_BEGIN_EXTERN_C
	
	  struct __atomic_flag_base
	  {
	    __atomic_flag_data_type _M_i;
	  };
	
	  _GLIBCXX_END_EXTERN_C
	
	#define ATOMIC_FLAG_INIT { 0 }
	
	  /// atomic_flag
	  struct atomic_flag : public __atomic_flag_base
	  {
	    atomic_flag() noexcept = default;
	    ~atomic_flag() noexcept = default;
	    atomic_flag(const atomic_flag&) = delete;
	    atomic_flag& operator=(const atomic_flag&) = delete;
	    atomic_flag& operator=(const atomic_flag&) volatile = delete;
	
	    // Conversion to ATOMIC_FLAG_INIT.
	    constexpr atomic_flag(bool __i) noexcept
	      : __atomic_flag_base{ _S_init(__i) }
	    { }
	
	    bool
	    test_and_set(memory_order __m = memory_order_seq_cst) noexcept
	    {
	      return __atomic_test_and_set (&_M_i, __m);
	    }
	
	    bool
	    test_and_set(memory_order __m = memory_order_seq_cst) volatile noexcept
	    {
	      return __atomic_test_and_set (&_M_i, __m);
	    }
	
	    void
	    clear(memory_order __m = memory_order_seq_cst) noexcept
	    {
	      memory_order __b = __m & __memory_order_mask;
	      __glibcxx_assert(__b != memory_order_consume);
	      __glibcxx_assert(__b != memory_order_acquire);
	      __glibcxx_assert(__b != memory_order_acq_rel);
	
	      __atomic_clear (&_M_i, __m);
	    }
	
	    void
	    clear(memory_order __m = memory_order_seq_cst) volatile noexcept
	    {
	      memory_order __b = __m & __memory_order_mask;
	      __glibcxx_assert(__b != memory_order_consume);
	      __glibcxx_assert(__b != memory_order_acquire);
	      __glibcxx_assert(__b != memory_order_acq_rel);
	
	      __atomic_clear (&_M_i, __m);
	    }
	
	  private:
	    static constexpr __atomic_flag_data_type
	    _S_init(bool __i)
	    { return __i ? __GCC_ATOMIC_TEST_AND_SET_TRUEVAL : 0; }
	  };
	
	
	  /// Base class for atomic integrals.
	  //
	  // For each of the integral types, define atomic_[integral type] struct
	  //
	  // atomic_bool     bool
	  // atomic_char     char
	  // atomic_schar    signed char
	  // atomic_uchar    unsigned char
	  // atomic_short    short
	  // atomic_ushort   unsigned short
	  // atomic_int      int
	  // atomic_uint     unsigned int
	  // atomic_long     long
	  // atomic_ulong    unsigned long
	  // atomic_llong    long long
	  // atomic_ullong   unsigned long long
	  // atomic_char16_t char16_t
	  // atomic_char32_t char32_t
	  // atomic_wchar_t  wchar_t
	  //
	  // NB: Assuming _ITp is an integral scalar type that is 1, 2, 4, or
	  // 8 bytes, since that is what GCC built-in functions for atomic
	  // memory access expect.
	  template<typename _ITp>
	    struct __atomic_base
	    {
	    private:
	      typedef _ITp 	__int_type;
	
	      __int_type 	_M_i;
	
	    public:
	      __atomic_base() noexcept = default;
	      ~__atomic_base() noexcept = default;
	      __atomic_base(const __atomic_base&) = delete;
	      __atomic_base& operator=(const __atomic_base&) = delete;
	      __atomic_base& operator=(const __atomic_base&) volatile = delete;
	
	      // Requires __int_type convertible to _M_i.
	      constexpr __atomic_base(__int_type __i) noexcept : _M_i (__i) { }
	
	      operator __int_type() const noexcept
	      { return load(); }
	
	      operator __int_type() const volatile noexcept
	      { return load(); }
	
	      __int_type
	      operator=(__int_type __i) noexcept
	      {
		store(__i);
		return __i;
	      }
	
	      __int_type
	      operator=(__int_type __i) volatile noexcept
	      {
		store(__i);
		return __i;
	      }
	
	      __int_type
	      operator++(int) noexcept
	      { return fetch_add(1); }
	
	      __int_type
	      operator++(int) volatile noexcept
	      { return fetch_add(1); }
	
	      __int_type
	      operator--(int) noexcept
	      { return fetch_sub(1); }
	
	      __int_type
	      operator--(int) volatile noexcept
	      { return fetch_sub(1); }
	
	      __int_type
	      operator++() noexcept
	      { return __atomic_add_fetch(&_M_i, 1, memory_order_seq_cst); }
	
	      __int_type
	      operator++() volatile noexcept
	      { return __atomic_add_fetch(&_M_i, 1, memory_order_seq_cst); }
	
	      __int_type
	      operator--() noexcept
	      { return __atomic_sub_fetch(&_M_i, 1, memory_order_seq_cst); }
	
	      __int_type
	      operator--() volatile noexcept
	      { return __atomic_sub_fetch(&_M_i, 1, memory_order_seq_cst); }
	
	      __int_type
	      operator+=(__int_type __i) noexcept
	      { return __atomic_add_fetch(&_M_i, __i, memory_order_seq_cst); }
	
	      __int_type
	      operator+=(__int_type __i) volatile noexcept
	      { return __atomic_add_fetch(&_M_i, __i, memory_order_seq_cst); }
	
	      __int_type
	      operator-=(__int_type __i) noexcept
	      { return __atomic_sub_fetch(&_M_i, __i, memory_order_seq_cst); }
	
	      __int_type
	      operator-=(__int_type __i) volatile noexcept
	      { return __atomic_sub_fetch(&_M_i, __i, memory_order_seq_cst); }
	
	      __int_type
	      operator&=(__int_type __i) noexcept
	      { return __atomic_and_fetch(&_M_i, __i, memory_order_seq_cst); }
	
	      __int_type
	      operator&=(__int_type __i) volatile noexcept
	      { return __atomic_and_fetch(&_M_i, __i, memory_order_seq_cst); }
	
	      __int_type
	      operator|=(__int_type __i) noexcept
	      { return __atomic_or_fetch(&_M_i, __i, memory_order_seq_cst); }
	
	      __int_type
	      operator|=(__int_type __i) volatile noexcept
	      { return __atomic_or_fetch(&_M_i, __i, memory_order_seq_cst); }
	
	      __int_type
	      operator^=(__int_type __i) noexcept
	      { return __atomic_xor_fetch(&_M_i, __i, memory_order_seq_cst); }
	
	      __int_type
	      operator^=(__int_type __i) volatile noexcept
	      { return __atomic_xor_fetch(&_M_i, __i, memory_order_seq_cst); }
	
	      bool
	      is_lock_free() const noexcept
	      { return __atomic_is_lock_free(sizeof(_M_i), nullptr); }
	
	      bool
	      is_lock_free() const volatile noexcept
	      { return __atomic_is_lock_free(sizeof(_M_i), nullptr); }
	
	      void
	      store(__int_type __i, memory_order __m = memory_order_seq_cst) noexcept
	      {
	        memory_order __b = __m & __memory_order_mask;
		__glibcxx_assert(__b != memory_order_acquire);
		__glibcxx_assert(__b != memory_order_acq_rel);
		__glibcxx_assert(__b != memory_order_consume);
	
		__atomic_store_n(&_M_i, __i, __m);
	      }
	
	      void
	      store(__int_type __i,
		    memory_order __m = memory_order_seq_cst) volatile noexcept
	      {
	        memory_order __b = __m & __memory_order_mask;
		__glibcxx_assert(__b != memory_order_acquire);
		__glibcxx_assert(__b != memory_order_acq_rel);
		__glibcxx_assert(__b != memory_order_consume);
	
		__atomic_store_n(&_M_i, __i, __m);
	      }
	
	      __int_type
	      load(memory_order __m = memory_order_seq_cst) const noexcept
	      {
	       memory_order __b = __m & __memory_order_mask;
		__glibcxx_assert(__b != memory_order_release);
		__glibcxx_assert(__b != memory_order_acq_rel);
	
		return __atomic_load_n(&_M_i, __m);
	      }
	
	      __int_type
	      load(memory_order __m = memory_order_seq_cst) const volatile noexcept
	      {
	        memory_order __b = __m & __memory_order_mask;
		__glibcxx_assert(__b != memory_order_release);
		__glibcxx_assert(__b != memory_order_acq_rel);
	
		return __atomic_load_n(&_M_i, __m);
	      }
	
	      __int_type
	      exchange(__int_type __i,
		       memory_order __m = memory_order_seq_cst) noexcept
	      {
		return __atomic_exchange_n(&_M_i, __i, __m);
	      }
	
	
	      __int_type
	      exchange(__int_type __i,
		       memory_order __m = memory_order_seq_cst) volatile noexcept
	      {
		return __atomic_exchange_n(&_M_i, __i, __m);
	      }
	
	      bool
	      compare_exchange_weak(__int_type& __i1, __int_type __i2,
				    memory_order __m1, memory_order __m2) noexcept
	      {
	       memory_order __b2 = __m2 & __memory_order_mask;
	       memory_order __b1 = __m1 & __memory_order_mask;
		__glibcxx_assert(__b2 != memory_order_release);
		__glibcxx_assert(__b2 != memory_order_acq_rel);
		__glibcxx_assert(__b2 <= __b1);
	
		return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 1, __m1, __m2);
	      }
	
	      bool
	      compare_exchange_weak(__int_type& __i1, __int_type __i2,
				    memory_order __m1,
				    memory_order __m2) volatile noexcept
	      {
	       memory_order __b2 = __m2 & __memory_order_mask;
	       memory_order __b1 = __m1 & __memory_order_mask;
		__glibcxx_assert(__b2 != memory_order_release);
		__glibcxx_assert(__b2 != memory_order_acq_rel);
		__glibcxx_assert(__b2 <= __b1);
	
		return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 1, __m1, __m2);
	      }
	
	      bool
	      compare_exchange_weak(__int_type& __i1, __int_type __i2,
				    memory_order __m = memory_order_seq_cst) noexcept
	      {
		return compare_exchange_weak(__i1, __i2, __m,
					     __cmpexch_failure_order(__m));
	      }
	
	      bool
	      compare_exchange_weak(__int_type& __i1, __int_type __i2,
			   memory_order __m = memory_order_seq_cst) volatile noexcept
	      {
		return compare_exchange_weak(__i1, __i2, __m,
					     __cmpexch_failure_order(__m));
	      }
	
	      bool
	      compare_exchange_strong(__int_type& __i1, __int_type __i2,
				      memory_order __m1, memory_order __m2) noexcept
	      {
	        memory_order __b2 = __m2 & __memory_order_mask;
	        memory_order __b1 = __m1 & __memory_order_mask;
		__glibcxx_assert(__b2 != memory_order_release);
		__glibcxx_assert(__b2 != memory_order_acq_rel);
		__glibcxx_assert(__b2 <= __b1);
	
		return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 0, __m1, __m2);
	      }
	
	      bool
	      compare_exchange_strong(__int_type& __i1, __int_type __i2,
				      memory_order __m1,
				      memory_order __m2) volatile noexcept
	      {
	        memory_order __b2 = __m2 & __memory_order_mask;
	        memory_order __b1 = __m1 & __memory_order_mask;
	
		__glibcxx_assert(__b2 != memory_order_release);
		__glibcxx_assert(__b2 != memory_order_acq_rel);
		__glibcxx_assert(__b2 <= __b1);
	
		return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 0, __m1, __m2);
	      }
	
	      bool
	      compare_exchange_strong(__int_type& __i1, __int_type __i2,
				      memory_order __m = memory_order_seq_cst) noexcept
	      {
		return compare_exchange_strong(__i1, __i2, __m,
					       __cmpexch_failure_order(__m));
	      }
	
	      bool
	      compare_exchange_strong(__int_type& __i1, __int_type __i2,
			 memory_order __m = memory_order_seq_cst) volatile noexcept
	      {
		return compare_exchange_strong(__i1, __i2, __m,
					       __cmpexch_failure_order(__m));
	      }
	
	      __int_type
	      fetch_add(__int_type __i,
			memory_order __m = memory_order_seq_cst) noexcept
	      { return __atomic_fetch_add(&_M_i, __i, __m); }
	
	      __int_type
	      fetch_add(__int_type __i,
			memory_order __m = memory_order_seq_cst) volatile noexcept
	      { return __atomic_fetch_add(&_M_i, __i, __m); }
	
	      __int_type
	      fetch_sub(__int_type __i,
			memory_order __m = memory_order_seq_cst) noexcept
	      { return __atomic_fetch_sub(&_M_i, __i, __m); }
	
	      __int_type
	      fetch_sub(__int_type __i,
			memory_order __m = memory_order_seq_cst) volatile noexcept
	      { return __atomic_fetch_sub(&_M_i, __i, __m); }
	
	      __int_type
	      fetch_and(__int_type __i,
			memory_order __m = memory_order_seq_cst) noexcept
	      { return __atomic_fetch_and(&_M_i, __i, __m); }
	
	      __int_type
	      fetch_and(__int_type __i,
			memory_order __m = memory_order_seq_cst) volatile noexcept
	      { return __atomic_fetch_and(&_M_i, __i, __m); }
	
	      __int_type
	      fetch_or(__int_type __i,
		       memory_order __m = memory_order_seq_cst) noexcept
	      { return __atomic_fetch_or(&_M_i, __i, __m); }
	
	      __int_type
	      fetch_or(__int_type __i,
		       memory_order __m = memory_order_seq_cst) volatile noexcept
	      { return __atomic_fetch_or(&_M_i, __i, __m); }
	
	      __int_type
	      fetch_xor(__int_type __i,
			memory_order __m = memory_order_seq_cst) noexcept
	      { return __atomic_fetch_xor(&_M_i, __i, __m); }
	
	      __int_type
	      fetch_xor(__int_type __i,
			memory_order __m = memory_order_seq_cst) volatile noexcept
	      { return __atomic_fetch_xor(&_M_i, __i, __m); }
	    };
	
	
	  /// Partial specialization for pointer types.
	  template<typename _PTp>
	    struct __atomic_base<_PTp*>
	    {
	    private:
	      typedef _PTp* 	__pointer_type;
	
	      __pointer_type 	_M_p;
	
	      // Factored out to facilitate explicit specialization.
	      constexpr ptrdiff_t
	      _M_type_size(ptrdiff_t __d) { return __d * sizeof(_PTp); }
	
	      constexpr ptrdiff_t
	      _M_type_size(ptrdiff_t __d) volatile { return __d * sizeof(_PTp); }
	
	    public:
	      __atomic_base() noexcept = default;
	      ~__atomic_base() noexcept = default;
	      __atomic_base(const __atomic_base&) = delete;
	      __atomic_base& operator=(const __atomic_base&) = delete;
	      __atomic_base& operator=(const __atomic_base&) volatile = delete;
	
	      // Requires __pointer_type convertible to _M_p.
	      constexpr __atomic_base(__pointer_type __p) noexcept : _M_p (__p) { }
	
	      operator __pointer_type() const noexcept
	      { return load(); }
	
	      operator __pointer_type() const volatile noexcept
	      { return load(); }
	
	      __pointer_type
	      operator=(__pointer_type __p) noexcept
	      {
		store(__p);
		return __p;
	      }
	
	      __pointer_type
	      operator=(__pointer_type __p) volatile noexcept
	      {
		store(__p);
		return __p;
	      }
	
	      __pointer_type
	      operator++(int) noexcept
	      { return fetch_add(1); }
	
	      __pointer_type
	      operator++(int) volatile noexcept
	      { return fetch_add(1); }
	
	      __pointer_type
	      operator--(int) noexcept
	      { return fetch_sub(1); }
	
	      __pointer_type
	      operator--(int) volatile noexcept
	      { return fetch_sub(1); }
	
	      __pointer_type
	      operator++() noexcept
	      { return __atomic_add_fetch(&_M_p, _M_type_size(1),
					  memory_order_seq_cst); }
	
	      __pointer_type
	      operator++() volatile noexcept
	      { return __atomic_add_fetch(&_M_p, _M_type_size(1),
					  memory_order_seq_cst); }
	
	      __pointer_type
	      operator--() noexcept
	      { return __atomic_sub_fetch(&_M_p, _M_type_size(1),
					  memory_order_seq_cst); }
	
	      __pointer_type
	      operator--() volatile noexcept
	      { return __atomic_sub_fetch(&_M_p, _M_type_size(1),
					  memory_order_seq_cst); }
	
	      __pointer_type
	      operator+=(ptrdiff_t __d) noexcept
	      { return __atomic_add_fetch(&_M_p, _M_type_size(__d),
					  memory_order_seq_cst); }
	
	      __pointer_type
	      operator+=(ptrdiff_t __d) volatile noexcept
	      { return __atomic_add_fetch(&_M_p, _M_type_size(__d),
					  memory_order_seq_cst); }
	
	      __pointer_type
	      operator-=(ptrdiff_t __d) noexcept
	      { return __atomic_sub_fetch(&_M_p, _M_type_size(__d),
					  memory_order_seq_cst); }
	
	      __pointer_type
	      operator-=(ptrdiff_t __d) volatile noexcept
	      { return __atomic_sub_fetch(&_M_p, _M_type_size(__d),
					  memory_order_seq_cst); }
	
	      bool
	      is_lock_free() const noexcept
	      { return __atomic_is_lock_free(_M_type_size(1), nullptr); }
	
	      bool
	      is_lock_free() const volatile noexcept
	      { return __atomic_is_lock_free(_M_type_size(1), nullptr); }
	
	      void
	      store(__pointer_type __p,
		    memory_order __m = memory_order_seq_cst) noexcept
	      {
	        memory_order __b = __m & __memory_order_mask;
	
		__glibcxx_assert(__b != memory_order_acquire);
		__glibcxx_assert(__b != memory_order_acq_rel);
		__glibcxx_assert(__b != memory_order_consume);
	
		__atomic_store_n(&_M_p, __p, __m);
	      }
	
	      void
	      store(__pointer_type __p,
		    memory_order __m = memory_order_seq_cst) volatile noexcept
	      {
	        memory_order __b = __m & __memory_order_mask;
		__glibcxx_assert(__b != memory_order_acquire);
		__glibcxx_assert(__b != memory_order_acq_rel);
		__glibcxx_assert(__b != memory_order_consume);
	
		__atomic_store_n(&_M_p, __p, __m);
	      }
	
	      __pointer_type
	      load(memory_order __m = memory_order_seq_cst) const noexcept
	      {
	        memory_order __b = __m & __memory_order_mask;
		__glibcxx_assert(__b != memory_order_release);
		__glibcxx_assert(__b != memory_order_acq_rel);
	
		return __atomic_load_n(&_M_p, __m);
	      }
	
	      __pointer_type
	      load(memory_order __m = memory_order_seq_cst) const volatile noexcept
	      {
	        memory_order __b = __m & __memory_order_mask;
		__glibcxx_assert(__b != memory_order_release);
		__glibcxx_assert(__b != memory_order_acq_rel);
	
		return __atomic_load_n(&_M_p, __m);
	      }
	
	      __pointer_type
	      exchange(__pointer_type __p,
		       memory_order __m = memory_order_seq_cst) noexcept
	      {
		return __atomic_exchange_n(&_M_p, __p, __m);
	      }
	
	
	      __pointer_type
	      exchange(__pointer_type __p,
		       memory_order __m = memory_order_seq_cst) volatile noexcept
	      {
		return __atomic_exchange_n(&_M_p, __p, __m);
	      }
	
	      bool
	      compare_exchange_strong(__pointer_type& __p1, __pointer_type __p2,
				      memory_order __m1,
				      memory_order __m2) noexcept
	      {
	        memory_order __b2 = __m2 & __memory_order_mask;
	        memory_order __b1 = __m1 & __memory_order_mask;
		__glibcxx_assert(__b2 != memory_order_release);
		__glibcxx_assert(__b2 != memory_order_acq_rel);
		__glibcxx_assert(__b2 <= __b1);
	
		return __atomic_compare_exchange_n(&_M_p, &__p1, __p2, 0, __m1, __m2);
	      }
	
	      bool
	      compare_exchange_strong(__pointer_type& __p1, __pointer_type __p2,
				      memory_order __m1,
				      memory_order __m2) volatile noexcept
	      {
	        memory_order __b2 = __m2 & __memory_order_mask;
	        memory_order __b1 = __m1 & __memory_order_mask;
	
		__glibcxx_assert(__b2 != memory_order_release);
		__glibcxx_assert(__b2 != memory_order_acq_rel);
		__glibcxx_assert(__b2 <= __b1);
	
		return __atomic_compare_exchange_n(&_M_p, &__p1, __p2, 0, __m1, __m2);
	      }
	
	      __pointer_type
	      fetch_add(ptrdiff_t __d,
			memory_order __m = memory_order_seq_cst) noexcept
	      { return __atomic_fetch_add(&_M_p, _M_type_size(__d), __m); }
	
	      __pointer_type
	      fetch_add(ptrdiff_t __d,
			memory_order __m = memory_order_seq_cst) volatile noexcept
	      { return __atomic_fetch_add(&_M_p, _M_type_size(__d), __m); }
	
	      __pointer_type
	      fetch_sub(ptrdiff_t __d,
			memory_order __m = memory_order_seq_cst) noexcept
	      { return __atomic_fetch_sub(&_M_p, _M_type_size(__d), __m); }
	
	      __pointer_type
	      fetch_sub(ptrdiff_t __d,
			memory_order __m = memory_order_seq_cst) volatile noexcept
	      { return __atomic_fetch_sub(&_M_p, _M_type_size(__d), __m); }
	    };
	
	  // @} group atomics
	
	_GLIBCXX_END_NAMESPACE_VERSION
	} // namespace std
	
	#endif