CXXD_MAKE_SHARED_HEADER — The make_shared header file name.
// In header: <boost/cxx_dual/impl/make_shared.hpp> CXXD_MAKE_SHARED_HEADER
The object-like macro expands to the include header file designation for the make_shared header file. The macro is used with the syntax: #include CXXD_MAKE_SHARED_HEADER
