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+/////////////////////////////////////////////////////////////////////////////
+//
+// (C) Copyright Ion Gaztanaga 2007-2009
+//
+// Distributed under 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/intrusive for documentation.
+//
+/////////////////////////////////////////////////////////////////////////////
+#ifndef BOOST_INTRUSIVE_DETAIL_PARENT_FROM_MEMBER_HPP
+#define BOOST_INTRUSIVE_DETAIL_PARENT_FROM_MEMBER_HPP
+
+#include <boost/intrusive/detail/config_begin.hpp>
+#include <cstddef>
+
+#if defined(BOOST_MSVC) || ((defined(_WIN32) || defined(__WIN32__) || defined(WIN32)) && defined(BOOST_INTEL))
+
+#define BOOST_INTRUSIVE_MSVC_COMPLIANT_PTR_TO_MEMBER
+#include <boost/cstdint.hpp>
+#endif
+
+namespace boost {
+namespace intrusive {
+namespace detail {
+
+template<class Parent, class Member>
+inline std::ptrdiff_t offset_from_pointer_to_member(const Member Parent::* ptr_to_member)
+{
+ //The implementation of a pointer to member is compiler dependent.
+ #if defined(BOOST_INTRUSIVE_MSVC_COMPLIANT_PTR_TO_MEMBER)
+ //msvc compliant compilers use their the first 32 bits as offset (even in 64 bit mode)
+ return *(const boost::int32_t*)(void*)&ptr_to_member;
+ //This works with gcc, msvc, ac++, ibmcpp
+ #elif defined(__GNUC__) || defined(__HP_aCC) || defined(BOOST_INTEL) || \
+ defined(__IBMCPP__) || defined(__DECCXX)
+ const Parent * const parent = 0;
+ const char *const member = reinterpret_cast<const char*>(&(parent->*ptr_to_member));
+ return std::ptrdiff_t(member - reinterpret_cast<const char*>(parent));
+ #else
+ //This is the traditional C-front approach: __MWERKS__, __DMC__, __SUNPRO_CC
+ return (*(const std::ptrdiff_t*)(void*)&ptr_to_member) - 1;
+ #endif
+}
+
+template<class Parent, class Member>
+inline Parent *parent_from_member(Member *member, const Member Parent::* ptr_to_member)
+{
+ return (Parent*)((char*)member - offset_from_pointer_to_member(ptr_to_member));
+}
+
+template<class Parent, class Member>
+inline const Parent *parent_from_member(const Member *member, const Member Parent::* ptr_to_member)
+{
+ return (const Parent*)((const char*)member - offset_from_pointer_to_member(ptr_to_member));
+}
+
+} //namespace detail {
+} //namespace intrusive {
+} //namespace boost {
+
+#ifdef BOOST_INTRUSIVE_MSVC_COMPLIANT_PTR_TO_MEMBER
+#undef BOOST_INTRUSIVE_MSVC_COMPLIANT_PTR_TO_MEMBER
+#endif
+
+#include <boost/intrusive/detail/config_end.hpp>
+
+#endif //#ifndef BOOST_INTRUSIVE_DETAIL_PARENT_FROM_MEMBER_HPP