id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc 11517,unused.hpp does not compile with g++ (<= 4.6) and -std=gnu++0x,Ben Goodrich ,Joel de Guzman,"To reproduce, try to execute {{{ g++-4.6 -std=gnu++0x -I. -o /tmp/unused.gch boost/fusion/support/unused.hpp }}} I obtain {{{ boost/fusion/support/unused.hpp: In member function ‘const boost::fusion::unused_type& boost::fusion::unused_type::operator=(const boost::fusion::unused_type&) const’: boost/fusion/support/unused.hpp:57:9: error: ‘this’ is not a potential constant expression boost/fusion/support/unused.hpp: At global scope: boost/fusion/support/unused.hpp:67:39: error: both ‘const’ and ‘constexpr’ cannot be used here }}} Such code later became acceptable to g++ but they did not backport the fix beyond 4.7.x ( [https://gcc.gnu.org/bugzilla/show_bug.cgi?id=54086] ). I am able to work around this problem by adding some lines like {{{ #if defined(__GXX_EXPERIMENTAL_CXX0X__) && __GNUC__ == 4 && __GNUC_MINOR__ <= 6 }}} in the attached file but you probably want a better fix.",Bugs,closed,Boost 1.59.0,fusion,Boost 1.58.0,Problem,fixed,,