./myfile/lib/libmy.a(my.o): In function `ZN4My6My_t4initERKNS0_10Settings_tE&#39;:<br>C:/Boost/include/boost-1_34_1/boost/filesystem/path.hpp:302: undefined reference to `boost::filesystem::detail::status_api(std::string const&amp;, unsigned int&amp;)&#39;
<br>./myfile/lib/libmy.a(my.o): In function `_tcf_0&#39;:<br>C:/CPW/cs_classes/./myfile/include/myerror.h:186: undefined reference to `boost::filesystem::detail::get_current_path_api(std::string&amp;)&#39;<br><br>i build boost linking to a built boost filesystem file using mingw 
3.4.5<br><br>including option. <br>-l&quot;boost_filesystem-mgw34-1_34_1&quot; <br><br>this is line 302 of path.hpp <br>&quot;const external_string_type external_file_string() const { return Traits::to_external( *this, file_string() ); }&quot;
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