I note that the test of ztest_max_digits10 and zztest_max_digits10 in http://www.boost.org/development/tests/trunk/developer/math.html both fail for these platforms. ztest_max_digits10 tests of native std::numeric_limits<>::max_digits10 is supported. zztest_max_digits10 test if BOOST_NO_NUMERIC_LIMITS_LOWEST is a proxy to signal support. where using std::numeric_limits<>::max_digits10 should be possible using BOOST_NO_NUMERIC_LIMITS_LOWEST as a proxy for Clang the messages are In file included from ../libs/math/test/zztest_max_digits10.cpp:27: In file included from ../boost/config.hpp:40: ../boost/config/select_stdlib_config.hpp:18:12: fatal error: 'cstddef' file not found # include <cstddef> In file included from ../libs/math/test/ztest_max_digits10.cpp:27: In file included from ../boost/config.hpp:40: ../boost/config/select_stdlib_config.hpp:18:12: fatal error: 'cstddef' file not found or for Cray CC-1353 crayc++: INTERNAL File = /opt/gcc/4.4.4/snos/include/g++/bits/move.h, Line = 34 CIF Error #include <cstddef> ^ This appears to be a problem in the config - a missing include. Suggestions? Paul --- Paul A. Bristow, Prizet Farmhouse, Kendal LA8 8AB UK +44 1539 561830 07714330204 pbristow@hetp.u-net.com