title: Link error with `boost::log2_mt` only on Ubuntu 32/64bits
body: <p>I have a huge project in which i use boost. boost come with my source tree in a specific folder where are header and lib for gcc 32 bits and 64bits in separate sub folder.</p>
  
  <p>on Centos : <code>Linux .... SMP Tue Jun 12 09:58:12 EDT 2012 x86_64 x86_64 x86_64 GNU/Linux</code><br>
  No problem every link fine.</p>
  
  <p>But the same source tree on Ubuntu: <code>Linux ... 3.2.0-48-generic #74-Ubuntu SMP Thu Jun 6 19:43:26 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux</code> fails dure to a linker error.</p>
  
  <pre><code>libtest.so: undefined reference to `boost::log2_mt_posix::aux::sem_based_event::~sem_based_event()'
  libtest.so: undefined reference to `boost::log2_mt_posix::aux::sem_based_event::sem_based_event()'
  libtest.so: undefined reference to `boost::log2_mt_posix::aux::sem_based_event::set_signalled()'
  libtest.so: undefined reference to `boost::log2_mt_posix::aux::sem_based_event::wait()'
  </code></pre>
  
  <p>below is the whole linker command line... Any help would be welcome !</p>
  
  <pre><code>/usr/bin/ccache  g++      -m32 -lrt -L/home/abuisson/dev/fwk/build/lin32_release -L/home/abuisson/dev/fwk/Source/../Libs/boost/Lin32 -L/home/abuisson/dev/fwk/Source/../Libs/ace/Lin32 -L/home/abuisson/dev/fwk/Source/../Libs/SafeNetRMS/Lin32 -L/home/abuisson/dev/fwk/Source/../Libs/OpenSSL/bin/out32StaticMTReleaseLinux -L/home/abuisson/dev/fwk/Source/../Libs/TinyXML/Lin32/ReleaseStaticMT -L/home/abuisson/dev/fwk/Source/../Libs/zlib/Lin32 -L/home/abuisson/dev/fwk/Source/../Libs/Curl/Lin32 -L/home/abuisson/dev/fwk/Source/../Libs/microhttpd/Lin32 -L/home/abuisson/dev/fwk/Source/../Libs/Intel/Linux32 -L/home/abuisson/dev/fwk/Source/../Libs/IPP/Lin32 -L/home/abuisson/dev/fwk/Source/../Libs/xerces/lin32 CMakeFiles/Frameworktst.dir/Framework/FrameworkTst/FrameworkTimerTst.cpp.o CMakeFiles/Frameworktst.dir/Framework/FrameworkTst/FrameworkTst.cpp.o CMakeFiles/Frameworktst.dir/Framework/FrameworkTst/WriterTst.cpp.o CMakeFiles/Frameworktst.dir/Framework/FrameworkTst/FrameworkLogTst.cpp.o  -o Frameworktst  libFramework.so libVersionInfoLib.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_thread-gcc41-mt-1_49.a -lpthread /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_system-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_date_time-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_regex-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_signals-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_filesystem-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_program_options-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_log-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_log_setup-gcc41-mt-1_49.a -lpthread -ldl -lrt libTestMediaPlugin.so libFramework.so libVersionInfoLib.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_thread-gcc41-mt-1_49.a -lpthread /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_system-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_date_time-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_regex-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_signals-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_filesystem-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_program_options-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_log-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_log_setup-gcc41-mt-1_49.a -lpthread -ldl -lrt libTestAlgorithmPlugin.so libFramework.so libVersionInfoLib.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_thread-gcc41-mt-1_49.a -lpthread /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_system-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_date_time-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_regex-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_signals-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_filesystem-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_program_options-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_log-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_log_setup-gcc41-mt-1_49.a -lpthread -ldl -lrt libTestChannel.so libFramework.so libVersionInfoLib.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_thread-gcc41-mt-1_49.a -lpthread /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_system-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_date_time-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_regex-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_signals-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_filesystem-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_program_options-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_log-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_log_setup-gcc41-mt-1_49.a -lpthread -ldl -lrt libYaffut.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_thread-gcc41-mt-1_49.a -lpthread /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_system-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_date_time-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_regex-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_signals-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_filesystem-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_program_options-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_log-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_log_setup-gcc41-mt-1_49.a -lpthread libWMCommon.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_thread-gcc41-mt-1_49.a -lpthread /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_system-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_date_time-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_regex-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_signals-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_filesystem-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_program_options-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_log-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_log_setup-gcc41-mt-1_49.a -lpthread /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_thread-gcc41-mt-1_49.a -lpthread /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_system-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_date_time-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_regex-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_signals-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_filesystem-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_program_options-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_log-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_log_setup-gcc41-mt-1_49.a -lpthread /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_system-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_date_time-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_regex-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_signals-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_filesystem-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_program_options-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_log-gcc41-mt-1_49.a /home/abuisson/dev/fwk/Libs/boost/Lin32/libboost_log_setup-gcc41-mt-1_49.a -ldl -lrt -Wl,-rpath,/home/abuisson/dev/fwk/build/lin32_release
  libFramework.so: undefined reference to `boost::log2_mt_posix::aux::sem_based_event::~sem_based_event()'
  libFramework.so: undefined reference to `boost::log2_mt_posix::aux::sem_based_event::sem_based_event()'
  libFramework.so: undefined reference to `boost::log2_mt_posix::aux::sem_based_event::set_signalled()'
  libFramework.so: undefined reference to `boost::log2_mt_posix::aux::sem_based_event::wait()'
  </code></pre>