When I use Spirit with CodeWarrior 9 (just released), I get a bunch of warnings as shown below. The CodeWarrior release notes explain that "According to the language standard, the '##' token pasting operator can only generate other tokens. This warning indicates when a paste was found that did not result in a token. The code will still compile as it did previously, but it may be a useful hint if the compiler emits an error later on." Warning : invalid token pasting of 'BOOST_PP_LIST_FIRST_I' and '(' (included from: expanding macro 'BOOST_PP_LIST_FIRST' expanding macro 'BOOST_PP_LIST_FOR_EACH_I_M_D' expanding macro 'BOOST_PP_LIST_FOR_EACH_I_M' expanding macro 'BOOST_PP_FOR_1_C' expanding macro 'BOOST_PP_FOR_1' expanding macro 'BOOST_PP_LIST_FOR_EACH_I' type_traits.hpp:58 composite.ipp:16 composite.hpp:15 directives.hpp:27 numerics.hpp:19 core.hpp:34 spirit.hpp:30 ParseCalcLine.cp:5) type_with_alignment.hpp line 55 on_ptr, BOOST_PP_NIL)))))))))))) -- http://www.jwwalker.com/