Hello, The following code compiles with 1.53, but fails with 1.54 (FreeBSD 9.1, gcc4.2.1): #include <boost/spirit/include/karma.hpp> #include <string> #include <iterator> int main() { using namespace boost::spirit::karma; std::string result; std::back_insert_iterator sink(result); unsigned short a; generate(sink, auto_, a); } The error is: boost/boost/math/tools/promotion.hpp: In instantiation of 'boost::math::tools::promote_args<long double, float, float, float, float, float>': boost/boost/math/special_functions/sign.hpp:114: instantiated from 'int boost::math::signbit(T) [with T = long double]' boost/boost/spirit/home/support/detail/sign.hpp:47: instantiated from 'bool boost::spirit::detail::signbit(T) [with T = long double]' boost/boost/spirit/home/karma/numeric/detail/numeric_utils.hpp:130: instantiated from here boost/boost/math/tools/promotion.hpp:141: error: invalid application of 'sizeof' to incomplete type 'boost::STATIC_ASSERTION_FAILURE<false>' I.e., the compilation fails because FreeBSD doesn't supprt "long double" type. This happens now due to the following changes in boost/math/special_functions/sign.hpp : 123 template<class T> int (signbit)(T x) 124 { 125 typedef typename detail::fp_traits<T>::type traits; 126 typedef typename traits::method method; 127 - typedef typename boost::is_floating_point<T>::type fp_tag; 128 - return detail::signbit_impl(x, method()); 127 + // typedef typename boost::is_floating_point<T>::type fp_tag; 128 + typedef typename tools::promote_args<T>::type result_type; 129 + return detail::signbit_impl(static_cast<result_type>(x), method()); 130 } So, what would be the right way to reconcile karma and math? Thanks, Igor'.