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+
+//  (C) Copyright John Maddock 2000.
+//  Use, modification and distribution are subject to the Boost Software License,
+//  Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt).
+//
+//  See http://www.boost.org/libs/type_traits for most recent version including documentation.
+
+#ifndef BOOST_TT_ALIGNMENT_OF_HPP_INCLUDED
+#define BOOST_TT_ALIGNMENT_OF_HPP_INCLUDED
+
+#include <boost/config.hpp>
+#include <cstddef>
+
+#include <boost/type_traits/intrinsics.hpp>
+#include <boost/type_traits/integral_constant.hpp>
+
+#ifdef BOOST_MSVC
+#   pragma warning(push)
+#   pragma warning(disable: 4121 4512) // alignment is sensitive to packing
+#endif
+#if defined(__BORLANDC__) && (__BORLANDC__ < 0x600)
+#pragma option push -Vx- -Ve-
+#endif
+
+namespace boost {
+
+template <typename T> struct alignment_of;
+
+// get the alignment of some arbitrary type:
+namespace detail {
+
+#ifdef BOOST_MSVC
+#pragma warning(push)
+#pragma warning(disable:4324) // structure was padded due to __declspec(align())
+#endif
+template <typename T>
+struct alignment_of_hack
+{
+    char c;
+    T t;
+    alignment_of_hack();
+};
+#ifdef BOOST_MSVC
+#pragma warning(pop)
+#endif
+
+template <unsigned A, unsigned S>
+struct alignment_logic
+{
+    BOOST_STATIC_CONSTANT(std::size_t, value = A < S ? A : S);
+};
+
+
+template< typename T >
+struct alignment_of_impl
+{
+#if defined(BOOST_MSVC) && (BOOST_MSVC >= 1400)
+    //
+    // With MSVC both the native __alignof operator
+    // and our own logic gets things wrong from time to time :-(
+    // Using a combination of the two seems to make the most of a bad job:
+    //
+    BOOST_STATIC_CONSTANT(std::size_t, value =
+        (::boost::detail::alignment_logic<
+            sizeof(::boost::detail::alignment_of_hack<T>) - sizeof(T),
+            __alignof(T)
+        >::value));
+#elif !defined(BOOST_ALIGNMENT_OF)
+    BOOST_STATIC_CONSTANT(std::size_t, value =
+        (::boost::detail::alignment_logic<
+            sizeof(::boost::detail::alignment_of_hack<T>) - sizeof(T),
+            sizeof(T)
+        >::value));
+#else
+   //
+   // We put this here, rather than in the definition of
+   // alignment_of below, because MSVC's __alignof doesn't
+   // always work in that context for some unexplained reason.
+   // (See type_with_alignment tests for test cases).
+   //
+   BOOST_STATIC_CONSTANT(std::size_t, value = BOOST_ALIGNMENT_OF(T));
+#endif
+};
+
+} // namespace detail
+
+template <class T> struct alignment_of : public integral_constant<std::size_t, ::boost::detail::alignment_of_impl<T>::value>{};
+
+// references have to be treated specially, assume
+// that a reference is just a special pointer:
+template <typename T> struct alignment_of<T&> : public alignment_of<T*>{};
+
+#ifdef __BORLANDC__
+// long double gives an incorrect value of 10 (!)
+// unless we do this...
+struct long_double_wrapper{ long double ld; };
+template<> struct alignment_of<long double> : public alignment_of<long_double_wrapper>{};
+#endif
+
+// void has to be treated specially:
+template<> struct alignment_of<void> : integral_constant<std::size_t, 0>{};
+#ifndef BOOST_NO_CV_VOID_SPECIALIZATIONS
+template<> struct alignment_of<void const> : integral_constant<std::size_t, 0>{};
+template<> struct alignment_of<void const volatile> : integral_constant<std::size_t, 0>{};
+template<> struct alignment_of<void volatile> : integral_constant<std::size_t, 0>{};
+#endif
+
+} // namespace boost
+
+#if defined(__BORLANDC__) && (__BORLANDC__ < 0x600)
+#pragma option pop
+#endif
+#ifdef BOOST_MSVC
+#   pragma warning(pop)
+#endif
+
+#endif // BOOST_TT_ALIGNMENT_OF_HPP_INCLUDED
+