http://www.boost.org/development/tests/develop/developer/summary.html show many "fails" due to: In file included from ../libs/chrono/src/process_cpu_clocks.cpp:17: In file included from ../boost/chrono/detail/inlined/process_cpu_clocks.hpp:19: In file included from ../boost/chrono/process_cpu_clocks.hpp:22: In file included from ../boost/chrono/detail/system.hpp:12: ../boost/system/error_code.hpp:431:15: error: 'detail' is not a class, namespace, or scoped enumeration { return *detail::throws(); } ^ ../boost/system/error_code.hpp:431:15: error: reference to 'detail' is ambiguous { return *detail::throws(); } ^ ../boost/system/error_code.hpp:421:13: note: candidate found by name lookup is 'boost::detail' namespace detail { inline system::error_code * throws() { return 0; } } ^ ../boost/operators.hpp:658:11: note: candidate found by name lookup is 'boost::operators_impl::detail' namespace detail ^ 2 errors generated. -- Markus