I'm running nightly local multi-platform builds using the boost trunk. The last two nights the Visual C++ 8.0 build (Windows XP 32-bit) was broken: C:\AUTOBU~3\sources\boost\boost/fusion/sequence/ comparison/less_equal.hpp(48) : error C2039: 'is_native_fusion_sequence' : is not a member of 'boost::fusion::detail' C:\AUTOBU~3\sources\boost\boost/fusion/sequence/comparison/less_equal.hpp(48) : error C2065: 'is_native_fusion_sequence' : undeclared identifier C:\AUTOBU~3\sources\boost\boost/fusion/sequence/comparison/less_equal.hpp(48) : error C2974: 'boost::disable_if' : invalid template argument for 'Cond', type expected C:\AUTOBU~3\sources\boost\boost/utility/enable_if.hpp(59) : see declaration of 'boost::disable_if' C:\AUTOBU~3\sources\boost\boost/fusion/sequence/comparison/less_equal.hpp(48) : error C2988: unrecognizable template declaration/definition C:\AUTOBU~3\sources\boost\boost/fusion/sequence/comparison/less_equal.hpp(48) : error C2059: syntax error : ',' C:\AUTOBU~3\sources\boost\boost/fusion/sequence/comparison/less_equal.hpp(48) : error C2039: 'type' : is not a member of '`global namespace'' boost svn rev. 68202 three nights ago still worked, rev. 68221 was the first I noticed that doesn't. VC 9 and 10 are fine, and so are many Linux and Mac builds. The failure is specific to VC 8. Ralf