https://svn.boost.org/trac10/ticket/12028 <p> I'm using Boost 1.58.0 with MSVS 2013 compiler, warning level 4, and treating warnings as errors. There is an unreferenced argument 'lk' at get_state. This should be fixed on a service pack for 1.58.0, please. </p> <p> ...\Boost_1_58_0\include\boost/thread/future.hpp(410): error C2220: warning treated as error - no 'object' file generated (Core\<a class="missing wiki">EventLoop</a>.cpp) ...\Boost_1_58_0\include\boost/thread/future.hpp(410): warning C4100: 'lk' : unreferenced formal parameter (Core\<a class="missing wiki">EventLoop</a>.cpp) </p> <p> future_state::state get_state(boost::unique_lock&lt;boost::mutex&gt;&amp; lk) const { </p> <blockquote> <p> if(!done) { </p> <blockquote> <p> return future_state::waiting; </p> </blockquote> <p> } else { </p> <blockquote> <p> return future_state::ready; </p> </blockquote> <p> } </p> </blockquote> <p> } </p> en-us /htdocs/site/boost.png https://svn.boost.org/trac10/ticket/12028 Trac 1.4.3 viboes Sun, 28 Feb 2016 18:18:40 GMT https://svn.boost.org/trac10/ticket/12028#comment:2 https://svn.boost.org/trac10/ticket/12028#comment:2 <ul> <li><strong>owner</strong> changed from <span class="trac-author">Anthony Williams</span> to <span class="trac-author">viboes</span> </li> <li><strong>status</strong> <span class="trac-field-old">new</span> → <span class="trac-field-new">assigned</span> </li> </ul> Ticket viboes Sun, 28 Feb 2016 18:33:44 GMT https://svn.boost.org/trac10/ticket/12028#comment:3 https://svn.boost.org/trac10/ticket/12028#comment:3 <ul> <li><strong>status</strong> <span class="trac-field-old">assigned</span> → <span class="trac-field-new">closed</span> </li> <li><strong>resolution</strong> → <span class="trac-field-new">worksforme</span> </li> <li><strong>milestone</strong> <span class="trac-field-deleted">To Be Determined</span> </li> </ul> <p> It was at least fixed in 1.60. </p> Ticket