Someone addvise to add the cflag BOOST_LOG_DYN_LINK. I think it is not all the truth.
To use the libboost_log, you should to know the cxxflag of the library when it build. Maybe the flag BOOST_LOG_DYN_LINK is not added into the build.
You should take care of the file
boost/log/detail/config.hpp about the BOOST_LOG_VERSION_NAMESPACE.
Anyway you should keep the same boost_log_version_namespace with the libboost_log that linked.
To check the boost_log_version_namespace can use the command:
nm -C libboost_log | grep push_record_move
push_record_move is one function of boost_log, it will output,like this,
boost::log::v2s_mt_posix::core::push_record_move(boost::log::v2s_mt_posix::record&)
v2s_mt_posix is the boost_log_version_namespace.