https://svn.boost.org/trac10/ticket/2756 <p> The following warning appears while compiling any usage of ptr_unordered_map with MSVC 9.0 SP1: </p> <pre class="wiki"> c:\boost\include\boost-1_38\boost\unordered\detail\hash_table.hpp(228) : warning C4100: 'x' : unreferenced formal parameter c:\boost\include\boost-1_38\boost\unordered\detail\hash_table_impl.hpp(175) : see reference to function template instantiation 'void boost::unordered_detail::destroy&lt;std::pair&lt;_Ty1,_Ty2&gt;&gt;(T *)' being compiled with [ _Ty1=const size_t, _Ty2=void *, T=std::pair&lt;const size_t,void *&gt; ] .............................................. c:\boost\include\boost-1_38\boost\ptr_container\ptr_unordered_map.hpp(37) : see reference to class template instantiation 'boost::ptr_map_adapter&lt;T,VoidPtrMap,CloneAllocator,Ordered&gt;' being compiled with [ T=mstd::pool, VoidPtrMap=boost::unordered_map&lt;size_t,void *,boost::hash&lt;unsigned int&gt;,std::equal_to&lt;size_t&gt;,std::allocator&lt;std::pair&lt;const size_t,void *&gt;&gt;&gt;, CloneAllocator=boost::heap_clone_allocator, Ordered=false ] </pre> en-us /htdocs/site/boost.png https://svn.boost.org/trac10/ticket/2756 Trac 1.4.3 Daniel James Mon, 30 Mar 2009 17:54:54 GMT https://svn.boost.org/trac10/ticket/2756#comment:1 https://svn.boost.org/trac10/ticket/2756#comment:1 <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> (In <a class="changeset" href="https://svn.boost.org/trac10/changeset/52065" title="Tweak unordered for some compilers. Fixes #2756. Merged revisions ...">[52065]</a>) Tweak unordered for some compilers. </p> <p> Fixes <a class="closed ticket" href="https://svn.boost.org/trac10/ticket/2756" title="#2756: Bugs: Warning while compiling ptr_unordered_map (closed: fixed)">#2756</a>. </p> <p> Merged revisions 51982-51983,51995 via svnmerge from <a class="ext-link" href="https://svn.boost.org/svn/boost/trunk"><span class="icon">​</span>https://svn.boost.org/svn/boost/trunk</a> </p> <p> ........ </p> <blockquote> <p> <a class="changeset" href="https://svn.boost.org/trac10/changeset/51982" title="Revert [51409] It isn't working on Borland.">r51982</a> | danieljames | 2009-03-26 07:00:21 +0000 (Thu, 26 Mar 2009) | 3 lines </p> </blockquote> <p> </p> <blockquote> <p> Revert <a class="changeset" href="https://svn.boost.org/trac10/changeset/51409" title="Move some of the data structure classes out of hash table data.">[51409]</a> </p> </blockquote> <p> </p> <blockquote> <p> It isn't working on Borland. </p> </blockquote> <p> ........ </p> <blockquote> <p> <a class="changeset" href="https://svn.boost.org/trac10/changeset/51983" title="Try to destruct values in a way that all compilers might like.">r51983</a> | danieljames | 2009-03-26 07:00:46 +0000 (Thu, 26 Mar 2009) | 1 line </p> </blockquote> <p> </p> <blockquote> <p> Try to destruct values in a way that all compilers might like. </p> </blockquote> <p> ........ </p> <blockquote> <p> <a class="changeset" href="https://svn.boost.org/trac10/changeset/51995" title="Give up and use another macro to destruct values.">r51995</a> | danieljames | 2009-03-26 21:09:51 +0000 (Thu, 26 Mar 2009) | 1 line </p> </blockquote> <p> </p> <blockquote> <p> Give up and use another macro to destruct values. </p> </blockquote> <p> ........ </p> Ticket