libitm: Conversion to c++11 atomics.

        * local_atomic: New file.
        * libitm_i.h: Include it.
        (gtm_thread::shared_state): Use atomic template.
        * beginend.cc (GTM::gtm_clock): Use atomic template.
        (global_tid): Use atomic template if 64-bit atomics available.
        (gtm_thread::gtm_thread): Update shared_state access.
        (gtm_thread::trycommit): Likewise.
        (choose_code_path): Update global_tid access.
        * method-gl.cc (gl_mg::orec): Use atomic template.  Update all users.
        * stmlock.h (GTM::gtm_clock): Use atomic template.
        (gtm_get_clock, gtm_inc_clock): Update accesses.
        * config/linux/rwlock.cc (gtm_rwlock::read_lock): Remove
        redundant __sync_synchronize after atomic shared_state access.
        * config/posix/rwlock.cc (gtm_rwlock::read_lock): Likewise.
        (gtm_rwlock::write_lock_generic): Likewise.
        (gtm_rwlock::read_unlock): Likewise.
        * config/alpha/target.h (atomic_read_barrier): Remove.
        (atomic_write_barrier): Remove.
        * config/x86/target.h (atomic_read_barrier): Remove.
        (atomic_write_barrier): Remove.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@182294 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 1903 insertions, 0 deletions

diff --git a/libitm/local_atomic b/libitm/local_atomic
new file mode 100644
index 00000000000..e6644634a73
--- /dev/null
+++ b/libitm/local_atomic
@@ -0,0 +1,1903 @@
+// -*- C++ -*- header.
+
+// Copyright (C) 2008, 2009, 2010, 2011 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/>.
+
+// ????????????????????????????????????????????????????????????????????
+//
+// This is a copy of the libstdc++ header, with the trivial modification
+// of ignoring the c++config.h include.  If and when the top-level build is
+// fixed so that target libraries can be built using the newly built, we can
+// delete this file.
+//
+// ????????????????????????????????????????????????????????????????????
+
+/** @file include/atomic
+ *  This is a Standard C++ Library header.
+ */
+
+// Based on "C++ Atomic Types and Operations" by Hans Boehm and Lawrence Crowl.
+// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2427.html
+
+#ifndef _GLIBCXX_ATOMIC
+#define _GLIBCXX_ATOMIC 1
+
+// #pragma GCC system_header
+
+// #ifndef __GXX_EXPERIMENTAL_CXX0X__
+// # include <bits/c++0x_warning.h>
+// #endif
+
+// #include <bits/atomic_base.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;
+
+  inline memory_order
+  __calculate_memory_order(memory_order __m) noexcept
+  {
+    const bool __cond1 = __m == memory_order_release;
+    const bool __cond2 = __m == memory_order_acq_rel;
+    memory_order __mo1(__cond1 ? memory_order_relaxed : __m);
+    memory_order __mo2(__cond2 ? memory_order_acquire : __mo1);
+    return __mo2;
+  }
+
+  inline void
+  atomic_thread_fence(memory_order __m) noexcept
+  {
+    __atomic_thread_fence (__m);
+  }
+
+  inline void
+  atomic_signal_fence(memory_order __m) noexcept
+  {
+    __atomic_thread_fence (__m);
+  }
+
+  /// kill_dependency
+  template<typename _Tp>
+    inline _Tp
+    kill_dependency(_Tp __y) noexcept
+    {
+      _Tp __ret(__y);
+      return __ret;
+    }
+
+  /// Lock-free Property
+
+
+#define ATOMIC_BOOL_LOCK_FREE		__GCC_ATOMIC_BOOL_LOCK_FREE
+#define ATOMIC_CHAR_LOCK_FREE		__GCC_ATOMIC_CHAR_LOCK_FREE
+#define ATOMIC_WCHAR_T_LOCK_FREE	__GCC_ATOMIC_WCHAR_T_LOCK_FREE
+#define ATOMIC_CHAR16_T_LOCK_FREE	__GCC_ATOMIC_CHAR16_T_LOCK_FREE
+#define ATOMIC_CHAR32_T_LOCK_FREE	__GCC_ATOMIC_CHAR32_T_LOCK_FREE
+#define ATOMIC_SHORT_LOCK_FREE		__GCC_ATOMIC_SHORT_LOCK_FREE
+#define ATOMIC_INT_LOCK_FREE		__GCC_ATOMIC_INT_LOCK_FREE
+#define ATOMIC_LONG_LOCK_FREE		__GCC_ATOMIC_LONG_LOCK_FREE
+#define ATOMIC_LLONG_LOCK_FREE		__GCC_ATOMIC_LLONG_LOCK_FREE
+#define ATOMIC_POINTER_LOCK_FREE	__GCC_ATOMIC_POINTER_LOCK_FREE
+
+  // 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*>;
+
+
+  /**
+   *  @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
+  {
+    bool _M_i;
+  };
+
+  // _GLIBCXX_END_EXTERN_C
+
+#define ATOMIC_FLAG_INIT { false }
+
+  /// 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.
+    atomic_flag(bool __i) noexcept : __atomic_flag_base({ __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
+    {
+      // __glibcxx_assert(__m != memory_order_consume);
+      // __glibcxx_assert(__m != memory_order_acquire);
+      // __glibcxx_assert(__m != memory_order_acq_rel);
+
+      __atomic_clear (&_M_i, __m);
+    }
+
+    void
+    clear(memory_order __m = memory_order_seq_cst) volatile noexcept
+    {
+      // __glibcxx_assert(__m != memory_order_consume);
+      // __glibcxx_assert(__m != memory_order_acquire);
+      // __glibcxx_assert(__m != memory_order_acq_rel);
+
+      __atomic_clear (&_M_i, __m);
+    }
+  };
+
+
+  /// 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), &_M_i); }
+
+      bool
+      is_lock_free() const volatile noexcept
+      { return __atomic_is_lock_free (sizeof (_M_i), &_M_i); }
+
+      void
+      store(__int_type __i, memory_order __m = memory_order_seq_cst) noexcept
+      {
+	// __glibcxx_assert(__m != memory_order_acquire);
+	// __glibcxx_assert(__m != memory_order_acq_rel);
+	// __glibcxx_assert(__m != memory_order_consume);
+
+	__atomic_store_n(&_M_i, __i, __m);
+      }
+
+      void
+      store(__int_type __i,
+	    memory_order __m = memory_order_seq_cst) volatile noexcept
+      {
+	// __glibcxx_assert(__m != memory_order_acquire);
+	// __glibcxx_assert(__m != memory_order_acq_rel);
+	// __glibcxx_assert(__m != memory_order_consume);
+
+	__atomic_store_n(&_M_i, __i, __m);
+      }
+
+      __int_type
+      load(memory_order __m = memory_order_seq_cst) const noexcept
+      {
+	// __glibcxx_assert(__m != memory_order_release);
+	// __glibcxx_assert(__m != memory_order_acq_rel);
+
+	return __atomic_load_n(&_M_i, __m);
+      }
+
+      __int_type
+      load(memory_order __m = memory_order_seq_cst) const volatile noexcept
+      {
+	// __glibcxx_assert(__m != memory_order_release);
+	// __glibcxx_assert(__m != 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
+      {
+	// __glibcxx_assert(__m2 != memory_order_release);
+	// __glibcxx_assert(__m2 != memory_order_acq_rel);
+	// __glibcxx_assert(__m2 <= __m1);
+
+	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
+      {
+	// __glibcxx_assert(__m2 != memory_order_release);
+	// __glibcxx_assert(__m2 != memory_order_acq_rel);
+	// __glibcxx_assert(__m2 <= __m1);
+
+	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,
+				     __calculate_memory_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,
+				     __calculate_memory_order(__m));
+      }
+
+      bool
+      compare_exchange_strong(__int_type& __i1, __int_type __i2,
+			      memory_order __m1, memory_order __m2) noexcept
+      {
+	// __glibcxx_assert(__m2 != memory_order_release);
+	// __glibcxx_assert(__m2 != memory_order_acq_rel);
+	// __glibcxx_assert(__m2 <= __m1);
+
+	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
+      {
+	// __glibcxx_assert(__m2 != memory_order_release);
+	// __glibcxx_assert(__m2 != memory_order_acq_rel);
+	// __glibcxx_assert(__m2 <= __m1);
+
+	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,
+				       __calculate_memory_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,
+				       __calculate_memory_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;
+
+    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, 1, memory_order_seq_cst); }
+
+      __pointer_type
+      operator++() volatile noexcept
+      { return __atomic_add_fetch(&_M_p, 1, memory_order_seq_cst); }
+
+      __pointer_type
+      operator--() noexcept
+      { return __atomic_sub_fetch(&_M_p, 1, memory_order_seq_cst); }
+
+      __pointer_type
+      operator--() volatile noexcept
+      { return __atomic_sub_fetch(&_M_p, 1, memory_order_seq_cst); }
+
+      __pointer_type
+      operator+=(ptrdiff_t __d) noexcept
+      { return __atomic_add_fetch(&_M_p, __d, memory_order_seq_cst); }
+
+      __pointer_type
+      operator+=(ptrdiff_t __d) volatile noexcept
+      { return __atomic_add_fetch(&_M_p, __d, memory_order_seq_cst); }
+
+      __pointer_type
+      operator-=(ptrdiff_t __d) noexcept
+      { return __atomic_sub_fetch(&_M_p, __d, memory_order_seq_cst); }
+
+      __pointer_type
+      operator-=(ptrdiff_t __d) volatile noexcept
+      { return __atomic_sub_fetch(&_M_p, __d, memory_order_seq_cst); }
+
+      bool
+      is_lock_free() const noexcept
+      { return __atomic_is_lock_free (sizeof (_M_p), &_M_p); }
+
+      bool
+      is_lock_free() const volatile noexcept
+      { return __atomic_is_lock_free (sizeof (_M_p), &_M_p); }
+
+      void
+      store(__pointer_type __p,
+	    memory_order __m = memory_order_seq_cst) noexcept
+      {
+	// __glibcxx_assert(__m != memory_order_acquire);
+	// __glibcxx_assert(__m != memory_order_acq_rel);
+	// __glibcxx_assert(__m != memory_order_consume);
+
+	__atomic_store_n(&_M_p, __p, __m);
+      }
+
+      void
+      store(__pointer_type __p,
+	    memory_order __m = memory_order_seq_cst) volatile noexcept
+      {
+	// __glibcxx_assert(__m != memory_order_acquire);
+	// __glibcxx_assert(__m != memory_order_acq_rel);
+	// __glibcxx_assert(__m != memory_order_consume);
+
+	__atomic_store_n(&_M_p, __p, __m);
+      }
+
+      __pointer_type
+      load(memory_order __m = memory_order_seq_cst) const noexcept
+      {
+	// __glibcxx_assert(__m != memory_order_release);
+	// __glibcxx_assert(__m != memory_order_acq_rel);
+
+	return __atomic_load_n(&_M_p, __m);
+      }
+
+      __pointer_type
+      load(memory_order __m = memory_order_seq_cst) const volatile noexcept
+      {
+	// __glibcxx_assert(__m != memory_order_release);
+	// __glibcxx_assert(__m != 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
+      {
+	// __glibcxx_assert(__m2 != memory_order_release);
+	// __glibcxx_assert(__m2 != memory_order_acq_rel);
+	// __glibcxx_assert(__m2 <= __m1);
+
+	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
+      {
+	// __glibcxx_assert(__m2 != memory_order_release);
+	// __glibcxx_assert(__m2 != memory_order_acq_rel);
+	// __glibcxx_assert(__m2 <= __m1);
+
+	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, __d, __m); }
+
+      __pointer_type
+      fetch_add(ptrdiff_t __d,
+		memory_order __m = memory_order_seq_cst) volatile noexcept
+      { return __atomic_fetch_add(&_M_p, __d, __m); }
+
+      __pointer_type
+      fetch_sub(ptrdiff_t __d,
+		memory_order __m = memory_order_seq_cst) noexcept
+      { return __atomic_fetch_sub(&_M_p, __d, __m); }
+
+      __pointer_type
+      fetch_sub(ptrdiff_t __d,
+		memory_order __m = memory_order_seq_cst) volatile noexcept
+      { return __atomic_fetch_sub(&_M_p, __d, __m); }
+    };
+
+
+  /**
+   * @addtogroup atomics
+   * @{
+   */
+
+  /// atomic_bool
+  // NB: No operators or fetch-operations for this type.
+  struct atomic_bool
+  {
+  private:
+    __atomic_base<bool>	_M_base;
+
+  public:
+    atomic_bool() noexcept = default;
+    ~atomic_bool() noexcept = default;
+    atomic_bool(const atomic_bool&) = delete;
+    atomic_bool& operator=(const atomic_bool&) = delete;
+    atomic_bool& operator=(const atomic_bool&) volatile = delete;
+
+    constexpr atomic_bool(bool __i) noexcept : _M_base(__i) { }
+
+    bool
+    operator=(bool __i) noexcept
+    { return _M_base.operator=(__i); }
+
+    operator bool() const noexcept
+    { return _M_base.load(); }
+
+    operator bool() const volatile noexcept
+    { return _M_base.load(); }
+
+    bool
+    is_lock_free() const noexcept { return _M_base.is_lock_free(); }
+
+    bool
+    is_lock_free() const volatile noexcept { return _M_base.is_lock_free(); }
+
+    void
+    store(bool __i, memory_order __m = memory_order_seq_cst) noexcept
+    { _M_base.store(__i, __m); }
+
+    void
+    store(bool __i, memory_order __m = memory_order_seq_cst) volatile noexcept
+    { _M_base.store(__i, __m); }
+
+    bool
+    load(memory_order __m = memory_order_seq_cst) const noexcept
+    { return _M_base.load(__m); }
+
+    bool
+    load(memory_order __m = memory_order_seq_cst) const volatile noexcept
+    { return _M_base.load(__m); }
+
+    bool
+    exchange(bool __i, memory_order __m = memory_order_seq_cst) noexcept
+    { return _M_base.exchange(__i, __m); }
+
+    bool
+    exchange(bool __i,
+	     memory_order __m = memory_order_seq_cst) volatile noexcept
+    { return _M_base.exchange(__i, __m); }
+
+    bool
+    compare_exchange_weak(bool& __i1, bool __i2, memory_order __m1,
+			  memory_order __m2) noexcept
+    { return _M_base.compare_exchange_weak(__i1, __i2, __m1, __m2); }
+
+    bool
+    compare_exchange_weak(bool& __i1, bool __i2, memory_order __m1,
+			  memory_order __m2) volatile noexcept
+    { return _M_base.compare_exchange_weak(__i1, __i2, __m1, __m2); }
+
+    bool
+    compare_exchange_weak(bool& __i1, bool __i2,
+			  memory_order __m = memory_order_seq_cst) noexcept
+    { return _M_base.compare_exchange_weak(__i1, __i2, __m); }
+
+    bool
+    compare_exchange_weak(bool& __i1, bool __i2,
+		     memory_order __m = memory_order_seq_cst) volatile noexcept
+    { return _M_base.compare_exchange_weak(__i1, __i2, __m); }
+
+    bool
+    compare_exchange_strong(bool& __i1, bool __i2, memory_order __m1,
+			    memory_order __m2) noexcept
+    { return _M_base.compare_exchange_strong(__i1, __i2, __m1, __m2); }
+
+    bool
+    compare_exchange_strong(bool& __i1, bool __i2, memory_order __m1,
+			    memory_order __m2) volatile noexcept
+    { return _M_base.compare_exchange_strong(__i1, __i2, __m1, __m2); }
+
+    bool
+    compare_exchange_strong(bool& __i1, bool __i2,
+			    memory_order __m = memory_order_seq_cst) noexcept
+    { return _M_base.compare_exchange_strong(__i1, __i2, __m); }
+
+    bool
+    compare_exchange_strong(bool& __i1, bool __i2,
+		    memory_order __m = memory_order_seq_cst) volatile noexcept
+    { return _M_base.compare_exchange_strong(__i1, __i2, __m); }
+  };
+
+
+  /// atomic
+  /// 29.4.3, Generic atomic type, primary class template.
+  template<typename _Tp>
+    struct atomic
+    {
+    private:
+      _Tp _M_i;
+
+    public:
+      atomic() noexcept = default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(_Tp __i) noexcept : _M_i(__i) { }
+
+      operator _Tp() const noexcept
+      { return load(); }
+
+      operator _Tp() const volatile noexcept
+      { return load(); }
+
+      _Tp
+      operator=(_Tp __i) noexcept 
+      { store(__i); return __i; }
+
+      _Tp
+      operator=(_Tp __i) volatile noexcept 
+      { store(__i); return __i; }
+
+      bool
+      is_lock_free() const noexcept
+      { return __atomic_is_lock_free(sizeof(_M_i), &_M_i); }
+
+      bool
+      is_lock_free() const volatile noexcept
+      { return __atomic_is_lock_free(sizeof(_M_i), &_M_i); }
+
+      void
+      store(_Tp __i, memory_order _m = memory_order_seq_cst) noexcept
+      { __atomic_store(&_M_i, &__i, _m); }
+
+      void
+      store(_Tp __i, memory_order _m = memory_order_seq_cst) volatile noexcept
+      { __atomic_store(&_M_i, &__i, _m); }
+
+      _Tp
+      load(memory_order _m = memory_order_seq_cst) const noexcept
+      { 
+        _Tp tmp;
+	__atomic_load(&_M_i, &tmp, _m); 
+	return tmp;
+      }
+
+      _Tp
+      load(memory_order _m = memory_order_seq_cst) const volatile noexcept
+      { 
+        _Tp tmp;
+	__atomic_load(&_M_i, &tmp, _m); 
+	return tmp;
+      }
+
+      _Tp
+      exchange(_Tp __i, memory_order _m = memory_order_seq_cst) noexcept
+      { 
+        _Tp tmp;
+	__atomic_exchange(&_M_i, &__i, &tmp, _m); 
+	return tmp;
+      }
+
+      _Tp
+      exchange(_Tp __i, 
+	       memory_order _m = memory_order_seq_cst) volatile noexcept
+      { 
+        _Tp tmp;
+	__atomic_exchange(&_M_i, &__i, &tmp, _m); 
+	return tmp;
+      }
+
+      bool
+      compare_exchange_weak(_Tp& __e, _Tp __i, memory_order __s, 
+			    memory_order __f) noexcept
+      {
+	return __atomic_compare_exchange(&_M_i, &__e, &__i, true, __s, __f); 
+      }
+
+      bool
+      compare_exchange_weak(_Tp& __e, _Tp __i, memory_order __s, 
+			    memory_order __f) volatile noexcept
+      {
+	return __atomic_compare_exchange(&_M_i, &__e, &__i, true, __s, __f); 
+      }
+
+      bool
+      compare_exchange_weak(_Tp& __e, _Tp __i,
+			    memory_order __m = memory_order_seq_cst) noexcept
+      { return compare_exchange_weak(__e, __i, __m, __m); }
+
+      bool
+      compare_exchange_weak(_Tp& __e, _Tp __i,
+		     memory_order __m = memory_order_seq_cst) volatile noexcept
+      { return compare_exchange_weak(__e, __i, __m, __m); }
+
+      bool
+      compare_exchange_strong(_Tp& __e, _Tp __i, memory_order __s, 
+			      memory_order __f) noexcept
+      {
+	return __atomic_compare_exchange(&_M_i, &__e, &__i, false, __s, __f); 
+      }
+
+      bool
+      compare_exchange_strong(_Tp& __e, _Tp __i, memory_order __s, 
+			      memory_order __f) volatile noexcept
+      {
+	return __atomic_compare_exchange(&_M_i, &__e, &__i, false, __s, __f); 
+      }
+
+      bool
+      compare_exchange_strong(_Tp& __e, _Tp __i,
+			       memory_order __m = memory_order_seq_cst) noexcept
+      { return compare_exchange_strong(__e, __i, __m, __m); }
+
+      bool
+      compare_exchange_strong(_Tp& __e, _Tp __i,
+		     memory_order __m = memory_order_seq_cst) volatile noexcept
+      { return compare_exchange_strong(__e, __i, __m, __m); }
+    };
+
+
+  /// Partial specialization for pointer types.
+  template<typename _Tp>
+    struct atomic<_Tp*>
+    {
+      typedef _Tp* 			__pointer_type;
+      typedef __atomic_base<_Tp*>	__base_type;
+      __base_type			_M_b;
+
+      atomic() noexcept = default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(__pointer_type __p) noexcept : _M_b(__p) { }
+
+      operator __pointer_type() const noexcept
+      { return __pointer_type(_M_b); }
+
+      operator __pointer_type() const volatile noexcept
+      { return __pointer_type(_M_b); }
+
+      __pointer_type
+      operator=(__pointer_type __p) noexcept
+      { return _M_b.operator=(__p); }
+
+      __pointer_type
+      operator=(__pointer_type __p) volatile noexcept
+      { return _M_b.operator=(__p); }
+
+      __pointer_type
+      operator++(int) noexcept
+      { return _M_b++; }
+
+      __pointer_type
+      operator++(int) volatile noexcept
+      { return _M_b++; }
+
+      __pointer_type
+      operator--(int) noexcept
+      { return _M_b--; }
+
+      __pointer_type
+      operator--(int) volatile noexcept
+      { return _M_b--; }
+
+      __pointer_type
+      operator++() noexcept
+      { return ++_M_b; }
+
+      __pointer_type
+      operator++() volatile noexcept
+      { return ++_M_b; }
+
+      __pointer_type
+      operator--() noexcept
+      { return --_M_b; }
+
+      __pointer_type
+      operator--() volatile noexcept
+      { return --_M_b; }
+
+      __pointer_type
+      operator+=(ptrdiff_t __d) noexcept
+      { return _M_b.operator+=(__d); }
+
+      __pointer_type
+      operator+=(ptrdiff_t __d) volatile noexcept
+      { return _M_b.operator+=(__d); }
+
+      __pointer_type
+      operator-=(ptrdiff_t __d) noexcept
+      { return _M_b.operator-=(__d); }
+
+      __pointer_type
+      operator-=(ptrdiff_t __d) volatile noexcept
+      { return _M_b.operator-=(__d); }
+
+      bool
+      is_lock_free() const noexcept
+      { return _M_b.is_lock_free(); }
+
+      bool
+      is_lock_free() const volatile noexcept
+      { return _M_b.is_lock_free(); }
+
+      void
+      store(__pointer_type __p,
+	    memory_order __m = memory_order_seq_cst) noexcept
+      { return _M_b.store(__p, __m); }
+
+      void
+      store(__pointer_type __p,
+	    memory_order __m = memory_order_seq_cst) volatile noexcept
+      { return _M_b.store(__p, __m); }
+
+      __pointer_type
+      load(memory_order __m = memory_order_seq_cst) const noexcept
+      { return _M_b.load(__m); }
+
+      __pointer_type
+      load(memory_order __m = memory_order_seq_cst) const volatile noexcept
+      { return _M_b.load(__m); }
+
+      __pointer_type
+      exchange(__pointer_type __p,
+	       memory_order __m = memory_order_seq_cst) noexcept
+      { return _M_b.exchange(__p, __m); }
+
+      __pointer_type
+      exchange(__pointer_type __p,
+	       memory_order __m = memory_order_seq_cst) volatile noexcept
+      { return _M_b.exchange(__p, __m); }
+
+      bool
+      compare_exchange_weak(__pointer_type& __p1, __pointer_type __p2,
+			    memory_order __m1, memory_order __m2) noexcept
+      { return _M_b.compare_exchange_strong(__p1, __p2, __m1, __m2); }
+
+      bool
+      compare_exchange_weak(__pointer_type& __p1, __pointer_type __p2,
+			    memory_order __m1,
+			    memory_order __m2) volatile noexcept
+      { return _M_b.compare_exchange_strong(__p1, __p2, __m1, __m2); }
+
+      bool
+      compare_exchange_weak(__pointer_type& __p1, __pointer_type __p2,
+			    memory_order __m = memory_order_seq_cst) noexcept
+      {
+	return compare_exchange_weak(__p1, __p2, __m,
+				     __calculate_memory_order(__m));
+      }
+
+      bool
+      compare_exchange_weak(__pointer_type& __p1, __pointer_type __p2,
+		    memory_order __m = memory_order_seq_cst) volatile noexcept
+      {
+	return compare_exchange_weak(__p1, __p2, __m,
+				     __calculate_memory_order(__m));
+      }
+
+      bool
+      compare_exchange_strong(__pointer_type& __p1, __pointer_type __p2,
+			      memory_order __m1, memory_order __m2) noexcept
+      { return _M_b.compare_exchange_strong(__p1, __p2, __m1, __m2); }
+
+      bool
+      compare_exchange_strong(__pointer_type& __p1, __pointer_type __p2,
+			      memory_order __m1,
+			      memory_order __m2) volatile noexcept
+      { return _M_b.compare_exchange_strong(__p1, __p2, __m1, __m2); }
+
+      bool
+      compare_exchange_strong(__pointer_type& __p1, __pointer_type __p2,
+			      memory_order __m = memory_order_seq_cst) noexcept
+      {
+	return _M_b.compare_exchange_strong(__p1, __p2, __m,
+					    __calculate_memory_order(__m));
+      }
+
+      bool
+      compare_exchange_strong(__pointer_type& __p1, __pointer_type __p2,
+		    memory_order __m = memory_order_seq_cst) volatile noexcept
+      {
+	return _M_b.compare_exchange_strong(__p1, __p2, __m,
+					    __calculate_memory_order(__m));
+      }
+
+      __pointer_type
+      fetch_add(ptrdiff_t __d,
+		memory_order __m = memory_order_seq_cst) noexcept
+      { return _M_b.fetch_add(__d, __m); }
+
+      __pointer_type
+      fetch_add(ptrdiff_t __d,
+		memory_order __m = memory_order_seq_cst) volatile noexcept
+      { return _M_b.fetch_add(__d, __m); }
+
+      __pointer_type
+      fetch_sub(ptrdiff_t __d,
+		memory_order __m = memory_order_seq_cst) noexcept
+      { return _M_b.fetch_sub(__d, __m); }
+
+      __pointer_type
+      fetch_sub(ptrdiff_t __d,
+		memory_order __m = memory_order_seq_cst) volatile noexcept
+      { return _M_b.fetch_sub(__d, __m); }
+    };
+
+
+  /// Explicit specialization for bool.
+  template<>
+    struct atomic<bool> : public atomic_bool
+    {
+      typedef bool 			__integral_type;
+      typedef atomic_bool 		__base_type;
+
+      atomic() noexcept = default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(__integral_type __i) noexcept : __base_type(__i) { }
+
+      using __base_type::operator __integral_type;
+      using __base_type::operator=;
+    };
+
+  /// Explicit specialization for char.
+  template<>
+    struct atomic<char> : public atomic_char
+    {
+      typedef char 			__integral_type;
+      typedef atomic_char 		__base_type;
+
+      atomic() noexcept = default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(__integral_type __i) noexcept : __base_type(__i) { }
+
+      using __base_type::operator __integral_type;
+      using __base_type::operator=;
+    };
+
+  /// Explicit specialization for signed char.
+  template<>
+    struct atomic<signed char> : public atomic_schar
+    {
+      typedef signed char 		__integral_type;
+      typedef atomic_schar 		__base_type;
+
+      atomic() noexcept= default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(__integral_type __i) noexcept : __base_type(__i) { }
+
+      using __base_type::operator __integral_type;
+      using __base_type::operator=;
+    };
+
+  /// Explicit specialization for unsigned char.
+  template<>
+    struct atomic<unsigned char> : public atomic_uchar
+    {
+      typedef unsigned char 		__integral_type;
+      typedef atomic_uchar 		__base_type;
+
+      atomic() noexcept= default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(__integral_type __i) noexcept : __base_type(__i) { }
+
+      using __base_type::operator __integral_type;
+      using __base_type::operator=;
+    };
+
+  /// Explicit specialization for short.
+  template<>
+    struct atomic<short> : public atomic_short
+    {
+      typedef short 			__integral_type;
+      typedef atomic_short 		__base_type;
+
+      atomic() noexcept = default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(__integral_type __i) noexcept : __base_type(__i) { }
+
+      using __base_type::operator __integral_type;
+      using __base_type::operator=;
+    };
+
+  /// Explicit specialization for unsigned short.
+  template<>
+    struct atomic<unsigned short> : public atomic_ushort
+    {
+      typedef unsigned short 	      	__integral_type;
+      typedef atomic_ushort 		__base_type;
+
+      atomic() noexcept = default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(__integral_type __i) noexcept : __base_type(__i) { }
+
+      using __base_type::operator __integral_type;
+      using __base_type::operator=;
+    };
+
+  /// Explicit specialization for int.
+  template<>
+    struct atomic<int> : atomic_int
+    {
+      typedef int 			__integral_type;
+      typedef atomic_int 		__base_type;
+
+      atomic() noexcept = default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(__integral_type __i) noexcept : __base_type(__i) { }
+
+      using __base_type::operator __integral_type;
+      using __base_type::operator=;
+    };
+
+  /// Explicit specialization for unsigned int.
+  template<>
+    struct atomic<unsigned int> : public atomic_uint
+    {
+      typedef unsigned int		__integral_type;
+      typedef atomic_uint 		__base_type;
+
+      atomic() noexcept = default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(__integral_type __i) noexcept : __base_type(__i) { }
+
+      using __base_type::operator __integral_type;
+      using __base_type::operator=;
+    };
+
+  /// Explicit specialization for long.
+  template<>
+    struct atomic<long> : public atomic_long
+    {
+      typedef long 			__integral_type;
+      typedef atomic_long 		__base_type;
+
+      atomic() noexcept = default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(__integral_type __i) noexcept : __base_type(__i) { }
+
+      using __base_type::operator __integral_type;
+      using __base_type::operator=;
+    };
+
+  /// Explicit specialization for unsigned long.
+  template<>
+    struct atomic<unsigned long> : public atomic_ulong
+    {
+      typedef unsigned long 		__integral_type;
+      typedef atomic_ulong 		__base_type;
+
+      atomic() noexcept = default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(__integral_type __i) noexcept : __base_type(__i) { }
+
+      using __base_type::operator __integral_type;
+      using __base_type::operator=;
+    };
+
+  /// Explicit specialization for long long.
+  template<>
+    struct atomic<long long> : public atomic_llong
+    {
+      typedef long long 		__integral_type;
+      typedef atomic_llong 		__base_type;
+
+      atomic() noexcept = default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(__integral_type __i) noexcept : __base_type(__i) { }
+
+      using __base_type::operator __integral_type;
+      using __base_type::operator=;
+    };
+
+  /// Explicit specialization for unsigned long long.
+  template<>
+    struct atomic<unsigned long long> : public atomic_ullong
+    {
+      typedef unsigned long long       	__integral_type;
+      typedef atomic_ullong 		__base_type;
+
+      atomic() noexcept = default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(__integral_type __i) noexcept : __base_type(__i) { }
+
+      using __base_type::operator __integral_type;
+      using __base_type::operator=;
+    };
+
+  /// Explicit specialization for wchar_t.
+  template<>
+    struct atomic<wchar_t> : public atomic_wchar_t
+    {
+      typedef wchar_t 			__integral_type;
+      typedef atomic_wchar_t 		__base_type;
+
+      atomic() noexcept = default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(__integral_type __i) noexcept : __base_type(__i) { }
+
+      using __base_type::operator __integral_type;
+      using __base_type::operator=;
+    };
+
+  /// Explicit specialization for char16_t.
+  template<>
+    struct atomic<char16_t> : public atomic_char16_t
+    {
+      typedef char16_t 			__integral_type;
+      typedef atomic_char16_t 		__base_type;
+
+      atomic() noexcept = default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(__integral_type __i) noexcept : __base_type(__i) { }
+
+      using __base_type::operator __integral_type;
+      using __base_type::operator=;
+    };
+
+  /// Explicit specialization for char32_t.
+  template<>
+    struct atomic<char32_t> : public atomic_char32_t
+    {
+      typedef char32_t 			__integral_type;
+      typedef atomic_char32_t 		__base_type;
+
+      atomic() noexcept = default;
+      ~atomic() noexcept = default;
+      atomic(const atomic&) = delete;
+      atomic& operator=(const atomic&) = delete;
+      atomic& operator=(const atomic&) volatile = delete;
+
+      constexpr atomic(__integral_type __i) noexcept : __base_type(__i) { }
+
+      using __base_type::operator __integral_type;
+      using __base_type::operator=;
+    };
+
+
+  // Function definitions, atomic_flag operations.
+  inline bool
+  atomic_flag_test_and_set_explicit(atomic_flag* __a,
+				    memory_order __m) noexcept
+  { return __a->test_and_set(__m); }
+
+  inline bool
+  atomic_flag_test_and_set_explicit(volatile atomic_flag* __a,
+				    memory_order __m) noexcept
+  { return __a->test_and_set(__m); }
+
+  inline void
+  atomic_flag_clear_explicit(atomic_flag* __a, memory_order __m) noexcept
+  { __a->clear(__m); }
+
+  inline void
+  atomic_flag_clear_explicit(volatile atomic_flag* __a,
+			     memory_order __m) noexcept
+  { __a->clear(__m); }
+
+  inline bool
+  atomic_flag_test_and_set(atomic_flag* __a) noexcept
+  { return atomic_flag_test_and_set_explicit(__a, memory_order_seq_cst); }
+
+  inline bool
+  atomic_flag_test_and_set(volatile atomic_flag* __a) noexcept
+  { return atomic_flag_test_and_set_explicit(__a, memory_order_seq_cst); }
+
+  inline void
+  atomic_flag_clear(atomic_flag* __a) noexcept
+  { atomic_flag_clear_explicit(__a, memory_order_seq_cst); }
+
+  inline void
+  atomic_flag_clear(volatile atomic_flag* __a) noexcept
+  { atomic_flag_clear_explicit(__a, memory_order_seq_cst); }
+
+
+  // Function templates generally applicable to atomic types.
+  template<typename _ITp>
+    inline bool
+    atomic_is_lock_free(const atomic<_ITp>* __a) noexcept
+    { return __a->is_lock_free(); }
+
+  template<typename _ITp>
+    inline bool
+    atomic_is_lock_free(const volatile atomic<_ITp>* __a) noexcept
+    { return __a->is_lock_free(); }
+
+  template<typename _ITp>
+    inline void
+    atomic_init(atomic<_ITp>* __a, _ITp __i) noexcept;
+
+  template<typename _ITp>
+    inline void
+    atomic_init(volatile atomic<_ITp>* __a, _ITp __i) noexcept;
+
+  template<typename _ITp>
+    inline void
+    atomic_store_explicit(atomic<_ITp>* __a, _ITp __i,
+			  memory_order __m) noexcept
+    { __a->store(__i, __m); }
+
+  template<typename _ITp>
+    inline void
+    atomic_store_explicit(volatile atomic<_ITp>* __a, _ITp __i,
+			  memory_order __m) noexcept
+    { __a->store(__i, __m); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_load_explicit(const atomic<_ITp>* __a, memory_order __m) noexcept
+    { return __a->load(__m); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_load_explicit(const volatile atomic<_ITp>* __a,
+			 memory_order __m) noexcept
+    { return __a->load(__m); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_exchange_explicit(atomic<_ITp>* __a, _ITp __i,
+			     memory_order __m) noexcept
+    { return __a->exchange(__i, __m); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_exchange_explicit(volatile atomic<_ITp>* __a, _ITp __i,
+			     memory_order __m) noexcept
+    { return __a->exchange(__i, __m); }
+
+  template<typename _ITp>
+    inline bool
+    atomic_compare_exchange_weak_explicit(atomic<_ITp>* __a,
+					  _ITp* __i1, _ITp __i2,
+					  memory_order __m1,
+					  memory_order __m2) noexcept
+    { return __a->compare_exchange_weak(*__i1, __i2, __m1, __m2); }
+
+  template<typename _ITp>
+    inline bool
+    atomic_compare_exchange_weak_explicit(volatile atomic<_ITp>* __a,
+					  _ITp* __i1, _ITp __i2,
+					  memory_order __m1,
+					  memory_order __m2) noexcept
+    { return __a->compare_exchange_weak(*__i1, __i2, __m1, __m2); }
+
+  template<typename _ITp>
+    inline bool
+    atomic_compare_exchange_strong_explicit(atomic<_ITp>* __a,
+					    _ITp* __i1, _ITp __i2,
+					    memory_order __m1,
+					    memory_order __m2) noexcept
+    { return __a->compare_exchange_strong(*__i1, __i2, __m1, __m2); }
+
+  template<typename _ITp>
+    inline bool
+    atomic_compare_exchange_strong_explicit(volatile atomic<_ITp>* __a,
+					    _ITp* __i1, _ITp __i2,
+					    memory_order __m1,
+					    memory_order __m2) noexcept
+    { return __a->compare_exchange_strong(*__i1, __i2, __m1, __m2); }
+
+
+  template<typename _ITp>
+    inline void
+    atomic_store(atomic<_ITp>* __a, _ITp __i) noexcept
+    { atomic_store_explicit(__a, __i, memory_order_seq_cst); }
+
+  template<typename _ITp>
+    inline void
+    atomic_store(volatile atomic<_ITp>* __a, _ITp __i) noexcept
+    { atomic_store_explicit(__a, __i, memory_order_seq_cst); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_load(const atomic<_ITp>* __a) noexcept
+    { return atomic_load_explicit(__a, memory_order_seq_cst); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_load(const volatile atomic<_ITp>* __a) noexcept
+    { return atomic_load_explicit(__a, memory_order_seq_cst); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_exchange(atomic<_ITp>* __a, _ITp __i) noexcept
+    { return atomic_exchange_explicit(__a, __i, memory_order_seq_cst); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_exchange(volatile atomic<_ITp>* __a, _ITp __i) noexcept
+    { return atomic_exchange_explicit(__a, __i, memory_order_seq_cst); }
+
+  template<typename _ITp>
+    inline bool
+    atomic_compare_exchange_weak(atomic<_ITp>* __a,
+				 _ITp* __i1, _ITp __i2) noexcept
+    {
+      return atomic_compare_exchange_weak_explicit(__a, __i1, __i2,
+						   memory_order_seq_cst,
+						   memory_order_seq_cst);
+    }
+
+  template<typename _ITp>
+    inline bool
+    atomic_compare_exchange_weak(volatile atomic<_ITp>* __a,
+				 _ITp* __i1, _ITp __i2) noexcept
+    {
+      return atomic_compare_exchange_weak_explicit(__a, __i1, __i2,
+						   memory_order_seq_cst,
+						   memory_order_seq_cst);
+    }
+
+  template<typename _ITp>
+    inline bool
+    atomic_compare_exchange_strong(atomic<_ITp>* __a,
+				   _ITp* __i1, _ITp __i2) noexcept
+    {
+      return atomic_compare_exchange_strong_explicit(__a, __i1, __i2,
+						     memory_order_seq_cst,
+						     memory_order_seq_cst);
+    }
+
+  template<typename _ITp>
+    inline bool
+    atomic_compare_exchange_strong(volatile atomic<_ITp>* __a,
+				   _ITp* __i1, _ITp __i2) noexcept
+    {
+      return atomic_compare_exchange_strong_explicit(__a, __i1, __i2,
+						     memory_order_seq_cst,
+						     memory_order_seq_cst);
+    }
+
+  // Function templates for atomic_integral operations only, using
+  // __atomic_base. Template argument should be constricted to
+  // intergral types as specified in the standard, excluding address
+  // types.
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_add_explicit(__atomic_base<_ITp>* __a, _ITp __i,
+			      memory_order __m) noexcept
+    { return __a->fetch_add(__i, __m); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_add_explicit(volatile __atomic_base<_ITp>* __a, _ITp __i,
+			      memory_order __m) noexcept
+    { return __a->fetch_add(__i, __m); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_sub_explicit(__atomic_base<_ITp>* __a, _ITp __i,
+			      memory_order __m) noexcept
+    { return __a->fetch_sub(__i, __m); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_sub_explicit(volatile __atomic_base<_ITp>* __a, _ITp __i,
+			      memory_order __m) noexcept
+    { return __a->fetch_sub(__i, __m); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_and_explicit(__atomic_base<_ITp>* __a, _ITp __i,
+			      memory_order __m) noexcept
+    { return __a->fetch_and(__i, __m); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_and_explicit(volatile __atomic_base<_ITp>* __a, _ITp __i,
+			      memory_order __m) noexcept
+    { return __a->fetch_and(__i, __m); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_or_explicit(__atomic_base<_ITp>* __a, _ITp __i,
+			     memory_order __m) noexcept
+    { return __a->fetch_or(__i, __m); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_or_explicit(volatile __atomic_base<_ITp>* __a, _ITp __i,
+			     memory_order __m) noexcept
+    { return __a->fetch_or(__i, __m); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_xor_explicit(__atomic_base<_ITp>* __a, _ITp __i,
+			      memory_order __m) noexcept
+    { return __a->fetch_xor(__i, __m); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_xor_explicit(volatile __atomic_base<_ITp>* __a, _ITp __i,
+			      memory_order __m) noexcept
+    { return __a->fetch_xor(__i, __m); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_add(__atomic_base<_ITp>* __a, _ITp __i) noexcept
+    { return atomic_fetch_add_explicit(__a, __i, memory_order_seq_cst); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_add(volatile __atomic_base<_ITp>* __a, _ITp __i) noexcept
+    { return atomic_fetch_add_explicit(__a, __i, memory_order_seq_cst); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_sub(__atomic_base<_ITp>* __a, _ITp __i) noexcept
+    { return atomic_fetch_sub_explicit(__a, __i, memory_order_seq_cst); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_sub(volatile __atomic_base<_ITp>* __a, _ITp __i) noexcept
+    { return atomic_fetch_sub_explicit(__a, __i, memory_order_seq_cst); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_and(__atomic_base<_ITp>* __a, _ITp __i) noexcept
+    { return atomic_fetch_and_explicit(__a, __i, memory_order_seq_cst); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_and(volatile __atomic_base<_ITp>* __a, _ITp __i) noexcept
+    { return atomic_fetch_and_explicit(__a, __i, memory_order_seq_cst); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_or(__atomic_base<_ITp>* __a, _ITp __i) noexcept
+    { return atomic_fetch_or_explicit(__a, __i, memory_order_seq_cst); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_or(volatile __atomic_base<_ITp>* __a, _ITp __i) noexcept
+    { return atomic_fetch_or_explicit(__a, __i, memory_order_seq_cst); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_xor(__atomic_base<_ITp>* __a, _ITp __i) noexcept
+    { return atomic_fetch_xor_explicit(__a, __i, memory_order_seq_cst); }
+
+  template<typename _ITp>
+    inline _ITp
+    atomic_fetch_xor(volatile __atomic_base<_ITp>* __a, _ITp __i) noexcept
+    { return atomic_fetch_xor_explicit(__a, __i, memory_order_seq_cst); }
+
+
+  // Partial specializations for pointers.
+  template<typename _ITp>
+    inline _ITp*
+    atomic_fetch_add_explicit(atomic<_ITp*>* __a, ptrdiff_t __d,
+			      memory_order __m) noexcept
+    { return __a->fetch_add(__d, __m); }
+
+  template<typename _ITp>
+    inline _ITp*
+    atomic_fetch_add_explicit(volatile atomic<_ITp*>* __a, ptrdiff_t __d,
+			      memory_order __m) noexcept
+    { return __a->fetch_add(__d, __m); }
+
+  template<typename _ITp>
+    inline _ITp*
+    atomic_fetch_add(volatile atomic<_ITp*>* __a, ptrdiff_t __d) noexcept
+    { return __a->fetch_add(__d); }
+
+  template<typename _ITp>
+    inline _ITp*
+    atomic_fetch_add(atomic<_ITp*>* __a, ptrdiff_t __d) noexcept
+    { return __a->fetch_add(__d); }
+
+  template<typename _ITp>
+    inline _ITp*
+    atomic_fetch_sub_explicit(volatile atomic<_ITp*>* __a,
+			      ptrdiff_t __d, memory_order __m) noexcept
+    { return __a->fetch_sub(__d, __m); }
+
+  template<typename _ITp>
+    inline _ITp*
+    atomic_fetch_sub_explicit(atomic<_ITp*>* __a, ptrdiff_t __d,
+			      memory_order __m) noexcept
+    { return __a->fetch_sub(__d, __m); }
+
+  template<typename _ITp>
+    inline _ITp*
+    atomic_fetch_sub(volatile atomic<_ITp*>* __a, ptrdiff_t __d) noexcept
+    { return __a->fetch_sub(__d); }
+
+  template<typename _ITp>
+    inline _ITp*
+    atomic_fetch_sub(atomic<_ITp*>* __a, ptrdiff_t __d) noexcept
+    { return __a->fetch_sub(__d); }
+  // @} group atomics
+
+// _GLIBCXX_END_NAMESPACE_VERSION
+} // namespace
+
+#endif