#include <boost/contract/detail/declspec.hpp>
#include <boost/thread/mutex.hpp>
#include <boost/noncopyable.hpp>
+#include <boost/config.hpp>
namespace boost { namespace contract { namespace detail {
#ifdef BOOST_MSVC
#pragma warning(push)
+ #pragma warning(disable: 4275) // Base w/o DLL spec (noncopyable).
#pragma warning(disable: 4251) // Member w/o DLL spec (mutex_ type).
#endif