https://svn.boost.org/trac10/ticket/12759 <p> Static constexpr members of boost::filesystem::path should have definitions. Currently they do not, which leads to, e.g., the following code not compiling: </p> <pre class="wiki">$ cat main.cpp #include &lt;boost/filesystem/path.hpp&gt; void f(const char &amp;) { } int main() { f(boost::filesystem::path::preferred_separator); } $ g++ -std=c++14 -lboost_filesystem -lboost_system main.cpp /tmp/ccuhjyO3.o: In function `main': main.cpp:(.text+0x12): undefined reference to `boost::filesystem::path::preferred_separator' collect2: error: ld returned 1 exit status </pre> en-us /htdocs/site/boost.png https://svn.boost.org/trac10/ticket/12759 Trac 1.4.3 Yegor Derevenets <yegor.derevenets@…> Fri, 13 Jan 2017 20:29:24 GMT https://svn.boost.org/trac10/ticket/12759#comment:2 https://svn.boost.org/trac10/ticket/12759#comment:2 <ul> <li><strong>status</strong> <span class="trac-field-old">new</span> → <span class="trac-field-new">closed</span> </li> <li><strong>resolution</strong> → <span class="trac-field-new">fixed</span> </li> </ul> <p> Fixed in <a class="ext-link" href="https://github.com/boostorg/filesystem/commit/8de281773f71b04b73c048a7b48e100cbfce92b0"><span class="icon">​</span>https://github.com/boostorg/filesystem/commit/8de281773f71b04b73c048a7b48e100cbfce92b0</a>. </p> Ticket