diff --git a/boost/smart_ptr/detail/spinlock.hpp b/boost/smart_ptr/detail/spinlock.hpp
new file mode 100644
index 0000000..88d7ad6
--- /dev/null
+++ b/boost/smart_ptr/detail/spinlock.hpp
@@ -0,0 +1,56 @@
+#ifndef BOOST_SMART_PTR_DETAIL_SPINLOCK_HPP_INCLUDED
+#define BOOST_SMART_PTR_DETAIL_SPINLOCK_HPP_INCLUDED
+
+// MS compatible compilers support #pragma once
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif
+
+//
+//  boost/detail/spinlock.hpp
+//
+//  Copyright (c) 2008 Peter Dimov
+//
+//  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)
+//
+//  struct spinlock
+//  {
+//      void lock();
+//      bool try_lock();
+//      void unlock();
+//
+//      class scoped_lock;
+//  };
+//
+//  #define BOOST_DETAIL_SPINLOCK_INIT <unspecified>
+//
+
+#include <boost/config.hpp>
+#include <boost/smart_ptr/detail/sp_has_sync.hpp>
+
+#if defined( BOOST_SP_USE_PTHREADS )
+#  include <boost/smart_ptr/detail/spinlock_pt.hpp>
+
+#elif defined(__GNUC__) && defined( __arm__ ) && !defined( __thumb__ )
+#  include <boost/smart_ptr/detail/spinlock_gcc_arm.hpp>
+
+#elif defined( BOOST_SP_HAS_SYNC )
+#  include <boost/smart_ptr/detail/spinlock_sync.hpp>
+
+#elif defined(WIN32) || defined(_WIN32) || defined(__WIN32__) || defined(__CYGWIN__)
+#  include <boost/smart_ptr/detail/spinlock_w32.hpp>
+
+#elif defined(BOOST_HAS_PTHREADS)
+#  include <boost/smart_ptr/detail/spinlock_pt.hpp>
+
+#elif !defined(BOOST_HAS_THREADS)
+#  include <boost/smart_ptr/detail/spinlock_nt.hpp>
+
+#else
+#  error Unrecognized threading platform
+#endif
+
+#endif // #ifndef BOOST_SMART_PTR_DETAIL_SPINLOCK_HPP_INCLUDED