I note that there are some new failing tests for circular buffer on some platforms http://www.boost.org/development/tests/trunk/developer/circular_buffer.html on MSVC noncopyable_movable_noexcept_t is causing trouble base_test.cpp C:\boost_regression\trunk\boost\boost/circular_buffer/base.hpp(694) : error C2558: struct 'noncopyable_movable_noexcept_t' : no copy constructor available or copy constructor is declared 'explicit' C:\boost_regression\trunk\boost\boost/circular_buffer/base.hpp(673) : while compiling class template member function 'noncopyable_movable_noexcept_t *boost::circular_buffer<T>::linearize(void)' with [ T=noncopyable_movable_test_t ] c:\boost_regression\trunk\boost\libs\circular_buffer\test\common.ipp(2160) : see reference to function template instantiation 'noncopyable_movable_noexcept_t *boost::circular_buffer<T>::linearize(void)' being compiled with [ T=noncopyable_movable_test_t ] c:\boost_regression\trunk\boost\libs\circular_buffer\test\common.ipp(2236) : see reference to class template instantiation 'boost::circular_buffer<T>' being compiled with [ T=noncopyable_movable_test_t ] C:\boost_regression\trunk\boost\boost/circular_buffer/base.hpp(697) : error C2558: struct 'noncopyable_movable_noexcept_t' : no copy constructor available or copy constructor is declared 'explicit' ON gcc and Clang there are warnings and failure Running 60 test cases... ../libs/circular_buffer/test/common.ipp(2303): error: in "check_containers_exception_specifications": check boost::has_nothrow_constructor::value has failed Can any experts shed light on this? I do not believe that the underlying circular buffer code has changed recently. Paul --- Paul A. Bristow, Prizet Farmhouse, Kendal LA8 8AB UK +44 1539 561830 07714330204 pbristow@hetp.u-net.com