Re-posting with more details: compiler : g++-4.0 with -Wall and -Werror enabled. I do not have the option to use GCC pragmas to disable specific warning from these headers. Also, I do not want to disable all warnings from boost by treating these as system headers. Any suggestions on what would be a good way to remove this particular warning. Thanks! ---------- Forwarded message ---------- From: samriti katoch <angelic.sam@gmail.com> Date: Tue, Apr 22, 2014 at 4:38 PM Subject: [msm] compilation warning with boost-1.55.0 To: boost-users@lists.boost.org Hi, With boost-1.55.0 I see this warning from msm code: In file included from /build/boost/fusion/include/make_map.hpp:10, from /build/boost/msm/front/euml/common.hpp:40, from /build/boost/msm/front/euml/operator.hpp:15, from /build/abc.cc:15: cc1plus: warnings being treated as errors /build/boost/msm/back/fold_to_list.hpp:35: warning: 'boost::msm::back::states_' defined but not used What is a good way to remove this warning? Thanks! Samriti