Hi, I have a project for Windows/Mac that builds fine using VS2010, but generates errors when I build using Xcode 4.6 with the Apple-provided GCC 4.2 compiler (required, as this project also uses wxWidgets). All of my own modules compile cleanly, but I get the following error output: SurfaceReader Group /users/tim/developer/libraries/boost_1_54_0/boost/type_traits/decay.hpp /users/tim/developer/libraries/boost_1_54_0/boost/type_traits/decay.hpp:28: '<anonymous enum>' is/uses anonymous type /users/tim/developer/libraries/boost_1_54_0/boost/type_traits/decay.hpp:28: Trying to instantiate 'template<class T> struct boost::remove_reference' /users/tim/developer/libraries/boost_1_54_0/boost/type_traits/decay.hpp:38: '<anonymous enum>' is/uses anonymous type /users/tim/developer/libraries/boost_1_54_0/boost/type_traits/decay.hpp:38: Trying to instantiate 'template<class T> struct boost::remove_reference' I realise that I haven't provided the command that Xcode is using to build the project - this isn't deliberate, but I can't seem to locate where Xcode provides this on-screen using the VoiceOver accessibility tool (I'm a totally blind developer). I don't include decay.hpp directly in any of my modules, but further research turned up: https://svn.boost.org/trac/boost/ticket/6362 If I can find the anonymous enum within the files included within decay.hpp I can patch it by providing a tag for the enum and I believe that this will rectify the issue. Can anybody point me at the appropriate file, or have I got to plough through the lot? I initially discovered this issue in Boost 1.54.0, but I can also reproduce it using 1.55.0. Many thanks in advance. Best wishes. Tim Burgess