I'm trying to build haiku with clang. So far I file a few bugs for clang http://llvm.org/bugs/show_bug.cgi?id=7207 and two for Haiku: http://dev.haiku-os.org/ticket/5875 (fixed) http://dev.haiku-os.org/ticket/5892 (not fixed yet)
Can I help? I am not a hardcore C++ expert, but still.