When building with -W -Wall, including <boost/xpressive/xpressive.hpp> produces a number of spurious warnings. GCC version: gcc version 4.1.3 20070831 (prerelease) (Ubuntu 4.1.2-16ubuntu1) Boost version: CVS (regression from 1.34.1) --- test program (build with -W -Wall) --- #include <boost/xpressive/xpressive.hpp> int main() { return 0; } --- end --- --- warning output --- bcvs/boost/boost/xpressive/regex_primitives.hpp:142: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::epsilon_matcher>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:149: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::epsilon_matcher>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:276: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::assert_bos_matcher>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:287: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::assert_eos_matcher>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:295: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::assert_bol_placeholder>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:303: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::assert_eol_placeholder>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:311: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::assert_word_placeholder<boost::xpressive::detail::word_begin>
, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:319: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::assert_word_placeholder<boost::xpressive::detail::word_end> , 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:329: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::assert_word_placeholder<boost::xpressive::detail::word_boundary<true>
, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:377: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::logical_newline_placeholder>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:386: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::any_matcher>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:395: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::self_placeholder>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:412: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::set_initializer>, 0l>::arg0' --- end output ---