https://svn.boost.org/trac10/ticket/4528 <p> It looks like x is not being passed in by reference. Because of this a copy is made on the stack. The operator returns x.value as a reference which is dangerous since x will go out of scope. </p> <p> This bug occurred with Xcode 4 beta 2, and with the latest version of clang/llvm from the open source project. </p> <p> CompileC /Users/bdoig/Library/Developer/Xcode/DerivedData/WDStoreTest-dbsxxdunpvzihagbzjvgylinzzaf/Build/Intermediates/WDStoreTest.build/Debug-iphonesimulator/WDStoreTest.build/Objects-normal/i386/TopoSort.o /Users/bdoig/Dropbox/WData/TopoSort.mm normal i386 objective-c++ com.apple.compilers.llvm.clang.1_0.compiler </p> <blockquote> <p> cd /Users/bdoig/Dropbox/WDStoreTest setenv LANG en_US.US-ASCII setenv PATH "/Xcode4/Platforms/iPhoneSimulator.platform/Developer/usr/bin:/Xcode4/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin" /Xcode4/Platforms/iPhoneSimulator.platform/Developer/usr/bin/clang -x objective-c++ -arch i386 -fmessage-length=0 -pipe -fdiagnostics-print-source-range-info -fdiagnostics-show-category=id -Wno-trigraphs -fpascal-strings -O0 -Wreturn-type -Wunused-variable -D<span class="underline">IPHONE_OS_VERSION_MIN_REQUIRED=30200 -isysroot /Xcode4/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator4.0.sdk -fasm-blocks -mmacosx-version-min=10.6 -gdwarf-2 -fvisibility=hidden -fobjc-abi-version=2 -fobjc-legacy-dispatch -iquote /Users/bdoig/Library/Developer/Xcode/DerivedData/WDStoreTest-dbsxxdunpvzihagbzjvgylinzzaf/Build/Intermediates/WDStoreTest.build/Debug-iphonesimulator/WDStoreTest.build/WDStoreTest-generated-files.hmap -I/Users/bdoig/Library/Developer/Xcode/DerivedData/WDStoreTest-dbsxxdunpvzihagbzjvgylinzzaf/Build/Intermediates/WDStoreTest.build/Debug-iphonesimulator/WDStoreTest.build/WDStoreTest-own-target-headers.hmap -I/Users/bdoig/Library/Developer/Xcode/DerivedData/WDStoreTest-dbsxxdunpvzihagbzjvgylinzzaf/Build/Intermediates/WDStoreTest.build/Debug-iphonesimulator/WDStoreTest.build/WDStoreTest-all-target-headers.hmap -iquote /Users/bdoig/Library/Developer/Xcode/DerivedData/WDStoreTest-dbsxxdunpvzihagbzjvgylinzzaf/Build/Intermediates/WDStoreTest.build/Debug-iphonesimulator/WDStoreTest.build/WDStoreTest-project-headers.hmap -F/Users/bdoig/Library/Developer/Xcode/DerivedData/WDStoreTest-dbsxxdunpvzihagbzjvgylinzzaf/Build/Products/Debug-iphonesimulator -I/Users/bdoig/Library/Developer/Xcode/DerivedData/WDStoreTest-dbsxxdunpvzihagbzjvgylinzzaf/Build/Products/Debug-iphonesimulator/include -I/Users/bdoig/Documents/Projects/boost_1_43_0 -I/Users/bdoig/Library/Developer/Xcode/DerivedData/WDStoreTest-dbsxxdunpvzihagbzjvgylinzzaf/Build/Intermediates/WDStoreTest.build/Debug-iphonesimulator/WDStoreTest.build/DerivedSources/i386 -I/Users/bdoig/Library/Developer/Xcode/DerivedData/WDStoreTest-dbsxxdunpvzihagbzjvgylinzzaf/Build/Intermediates/WDStoreTest.build/Debug-iphonesimulator/WDStoreTest.build/DerivedSources -include /Users/bdoig/Library/Developer/Xcode/DerivedData/WDStoreTest-dbsxxdunpvzihagbzjvgylinzzaf/Build/PrecompiledHeaders/WDStoreTest_Prefix-bwcwseswayysywfpkcwdmibmtjef/WDStoreTest_Prefix.pch -c /Users/bdoig/Dropbox/WData/TopoSort.mm -o /Users/bdoig/Library/Developer/Xcode/DerivedData/WDStoreTest-dbsxxdunpvzihagbzjvgylinzzaf/Build/Intermediates/WDStoreTest.build/Debug-iphonesimulator/WDStoreTest.build/Objects-normal/i386/TopoSort.o </span></p> </blockquote> <p> In file included from /Users/bdoig/Dropbox/WData/TopoSort.mm:11: In file included from /Users/bdoig/Dropbox/WData/TopoSort.h:20: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/topological_sort.hpp:16: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/depth_first_search.hpp:21: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/named_function_params.hpp:15: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/parameter/name.hpp:8: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/parameter/keyword.hpp:10: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/parameter/aux_/tag.hpp:8: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/parameter/aux_/tagged_argument.hpp:10: /Users/bdoig/Documents/Projects/boost_1_43_0/boost/parameter/aux_/arg_list.hpp:127:16:{127:16-127:23}: warning: reference to stack memory associated with local variable 'x' returned <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> return x.value; </p> <blockquote> <p> ^{<del></del><del> </del>}</p> </blockquote> </blockquote> <p> In file included from /Users/bdoig/Dropbox/WData/TopoSort.mm:11: In file included from /Users/bdoig/Dropbox/WData/TopoSort.h:20: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/topological_sort.hpp:16: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/depth_first_search.hpp:21: /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/named_function_params.hpp:408:19: note: in instantiation of function template specialization 'boost::parameter::aux::empty_arg_list::operator[]&lt;boost::graph::keywords::tag::vertex_index_map, int const&gt;' requested here <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote class="citation"> <p> ()(g, ap[t | 0]); </p> </blockquote> <blockquote> <p> </p> </blockquote> <p> /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/named_function_params.hpp:472:18: note: in instantiation of function template specialization 'boost::detail::override_const_property&lt;boost::parameter::aux::arg_list&lt;boost::parameter::aux::tagged_argument&lt;boost::graph::keywords::tag::visitor, boost::topo_sort_visitor&lt;std::front_insert_iterator&lt;std::deque&lt;int, std::allocator&lt;int&gt; &gt; &gt; &gt; const&gt;, boost::parameter::aux::arg_list&lt;boost::parameter::aux::tagged_argument&lt;boost::graph::keywords::tag::buffer, int const&gt;, boost::parameter::aux::empty_arg_list&gt; &gt;, boost::graph::keywords::tag::vertex_index_map, boost::vertex_index_t, boost::adjacency_list&lt;boost::listS, boost::vecS, boost::directedS, TopoVertexProperty, boost::no_property, boost::no_property, boost::listS&gt; &gt;' requested here <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> override_const_property( </p> </blockquote> <p> /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/named_function_params.hpp:496:24: note: in instantiation of member function 'boost::detail::color_map_maker_helper&lt;0, boost::adjacency_list&lt;boost::listS, boost::vecS, boost::directedS, TopoVertexProperty, boost::no_property, boost::no_property, boost::listS&gt;, boost::parameter::aux::arg_list&lt;boost::parameter::aux::tagged_argument&lt;boost::graph::keywords::tag::visitor, boost::topo_sort_visitor&lt;std::front_insert_iterator&lt;std::deque&lt;int, std::allocator&lt;int&gt; &gt; &gt; &gt; const&gt;, boost::parameter::aux::arg_list&lt;boost::parameter::aux::tagged_argument&lt;boost::graph::keywords::tag::buffer, int const&gt;, boost::parameter::aux::empty_arg_list&gt; &gt;, boost::default_color_type, int&gt;::make_map' requested here <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> return helper::make_map(g, white_color, ap[boost::graph::keywords::_color_map | 0], ap); </p> <blockquote> <p> </p> </blockquote> </blockquote> <p> In file included from /Users/bdoig/Dropbox/WData/TopoSort.mm:11: In file included from /Users/bdoig/Dropbox/WData/TopoSort.h:20: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/topological_sort.hpp:16: /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/depth_first_search.hpp:300:72: note: in instantiation of member function 'boost::detail::color_map_maker&lt;boost::adjacency_list&lt;boost::listS, boost::vecS, boost::directedS, TopoVertexProperty, boost::no_property, boost::no_property, boost::listS&gt;, boost::parameter::aux::arg_list&lt;boost::parameter::aux::tagged_argument&lt;boost::graph::keywords::tag::visitor, boost::topo_sort_visitor&lt;std::front_insert_iterator&lt;std::deque&lt;int, std::allocator&lt;int&gt; &gt; &gt; &gt; const&gt;, boost::parameter::aux::arg_list&lt;boost::parameter::aux::tagged_argument&lt;boost::graph::keywords::tag::buffer, int const&gt;, boost::parameter::aux::empty_arg_list&gt; &gt; &gt;::make_map' requested here <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> boost::detail::color_map_maker&lt;<a class="missing wiki">VertexListGraph</a>, arg_pack_type&gt;::make_map(g, arg_pack), </p> <blockquote> <p> </p> </blockquote> </blockquote> <p> In file included from /Users/bdoig/Dropbox/WData/TopoSort.mm:11: In file included from /Users/bdoig/Dropbox/WData/TopoSort.h:20: /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/topological_sort.hpp:65:5: note: in instantiation of function template specialization 'boost::depth_first_search&lt;boost::adjacency_list&lt;boost::listS, boost::vecS, boost::directedS, TopoVertexProperty, boost::no_property, boost::no_property, boost::listS&gt;, boost::topo_sort_visitor&lt;std::front_insert_iterator&lt;std::deque&lt;int, std::allocator&lt;int&gt; &gt; &gt; &gt;, boost::graph_visitor_t, boost::bgl_named_params&lt;int, boost::buffer_param_t, boost::no_property&gt; &gt;' requested here <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> depth_first_search(g, params.visitor(<a class="missing wiki">TopoVisitor</a>(result))); </p> </blockquote> <p> /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/topological_sort.hpp:71:5: note: in instantiation of function template specialization 'boost::topological_sort&lt;boost::adjacency_list&lt;boost::listS, boost::vecS, boost::directedS, TopoVertexProperty, boost::no_property, boost::no_property, boost::listS&gt;, std::front_insert_iterator&lt;std::deque&lt;int, std::allocator&lt;int&gt; &gt; &gt;, int, boost::buffer_param_t, boost::no_property&gt;' requested here <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> topological_sort(g, result, </p> </blockquote> <p> /Users/bdoig/Dropbox/WData/TopoSort.mm:20:3: note: in instantiation of function template specialization 'boost::topological_sort&lt;boost::adjacency_list&lt;boost::listS, boost::vecS, boost::directedS, TopoVertexProperty, boost::no_property, boost::no_property, boost::listS&gt;, std::front_insert_iterator&lt;std::deque&lt;int, std::allocator&lt;int&gt; &gt; &gt; &gt;' requested here <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> boost::topological_sort(vectorList, std::front_inserter(topo_order)); </p> </blockquote> <p> In file included from /Users/bdoig/Dropbox/WData/TopoSort.mm:11: In file included from /Users/bdoig/Dropbox/WData/TopoSort.h:20: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/topological_sort.hpp:16: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/depth_first_search.hpp:21: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/named_function_params.hpp:15: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/parameter/name.hpp:8: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/parameter/keyword.hpp:10: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/parameter/aux_/tag.hpp:8: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/parameter/aux_/tagged_argument.hpp:10: /Users/bdoig/Documents/Projects/boost_1_43_0/boost/parameter/aux_/arg_list.hpp:127:16:{127:16-127:23}: warning: reference to stack memory associated with local variable 'x' returned <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> return x.value; </p> <blockquote> <p> ^{<del></del><del> </del>}</p> </blockquote> </blockquote> <p> In file included from /Users/bdoig/Dropbox/WData/TopoSort.mm:11: In file included from /Users/bdoig/Dropbox/WData/TopoSort.h:20: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/topological_sort.hpp:16: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/depth_first_search.hpp:21: /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/named_function_params.hpp:496:49: note: in instantiation of function template specialization 'boost::parameter::aux::empty_arg_list::operator[]&lt;boost::graph::keywords::tag::color_map, int const&gt;' requested here <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> return helper::make_map(g, white_color, ap[boost::graph::keywords::_color_map | 0], ap); </p> <blockquote> <p> </p> </blockquote> </blockquote> <p> In file included from /Users/bdoig/Dropbox/WData/TopoSort.mm:11: In file included from /Users/bdoig/Dropbox/WData/TopoSort.h:20: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/topological_sort.hpp:16: /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/depth_first_search.hpp:300:72: note: in instantiation of member function 'boost::detail::color_map_maker&lt;boost::adjacency_list&lt;boost::listS, boost::vecS, boost::directedS, TopoVertexProperty, boost::no_property, boost::no_property, boost::listS&gt;, boost::parameter::aux::arg_list&lt;boost::parameter::aux::tagged_argument&lt;boost::graph::keywords::tag::visitor, boost::topo_sort_visitor&lt;std::front_insert_iterator&lt;std::deque&lt;int, std::allocator&lt;int&gt; &gt; &gt; &gt; const&gt;, boost::parameter::aux::arg_list&lt;boost::parameter::aux::tagged_argument&lt;boost::graph::keywords::tag::buffer, int const&gt;, boost::parameter::aux::empty_arg_list&gt; &gt; &gt;::make_map' requested here <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> boost::detail::color_map_maker&lt;<a class="missing wiki">VertexListGraph</a>, arg_pack_type&gt;::make_map(g, arg_pack), </p> <blockquote> <p> </p> </blockquote> </blockquote> <p> In file included from /Users/bdoig/Dropbox/WData/TopoSort.mm:11: In file included from /Users/bdoig/Dropbox/WData/TopoSort.h:20: /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/topological_sort.hpp:65:5: note: in instantiation of function template specialization 'boost::depth_first_search&lt;boost::adjacency_list&lt;boost::listS, boost::vecS, boost::directedS, TopoVertexProperty, boost::no_property, boost::no_property, boost::listS&gt;, boost::topo_sort_visitor&lt;std::front_insert_iterator&lt;std::deque&lt;int, std::allocator&lt;int&gt; &gt; &gt; &gt;, boost::graph_visitor_t, boost::bgl_named_params&lt;int, boost::buffer_param_t, boost::no_property&gt; &gt;' requested here <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> depth_first_search(g, params.visitor(<a class="missing wiki">TopoVisitor</a>(result))); </p> </blockquote> <p> /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/topological_sort.hpp:71:5: note: in instantiation of function template specialization 'boost::topological_sort&lt;boost::adjacency_list&lt;boost::listS, boost::vecS, boost::directedS, TopoVertexProperty, boost::no_property, boost::no_property, boost::listS&gt;, std::front_insert_iterator&lt;std::deque&lt;int, std::allocator&lt;int&gt; &gt; &gt;, int, boost::buffer_param_t, boost::no_property&gt;' requested here <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> topological_sort(g, result, </p> </blockquote> <p> /Users/bdoig/Dropbox/WData/TopoSort.mm:20:3: note: in instantiation of function template specialization 'boost::topological_sort&lt;boost::adjacency_list&lt;boost::listS, boost::vecS, boost::directedS, TopoVertexProperty, boost::no_property, boost::no_property, boost::listS&gt;, std::front_insert_iterator&lt;std::deque&lt;int, std::allocator&lt;int&gt; &gt; &gt; &gt;' requested here <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> boost::topological_sort(vectorList, std::front_inserter(topo_order)); </p> </blockquote> <p> In file included from /Users/bdoig/Dropbox/WData/TopoSort.mm:11: In file included from /Users/bdoig/Dropbox/WData/TopoSort.h:20: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/topological_sort.hpp:16: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/depth_first_search.hpp:21: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/named_function_params.hpp:15: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/parameter/name.hpp:8: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/parameter/keyword.hpp:10: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/parameter/aux_/tag.hpp:8: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/parameter/aux_/tagged_argument.hpp:10: /Users/bdoig/Documents/Projects/boost_1_43_0/boost/parameter/aux_/arg_list.hpp:127:16:{127:16-127:23}: warning: reference to stack memory associated with local variable 'x' returned <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> return x.value; </p> <blockquote> <p> ^{<del></del><del> </del>}</p> </blockquote> </blockquote> <p> In file included from /Users/bdoig/Dropbox/WData/TopoSort.mm:11: In file included from /Users/bdoig/Dropbox/WData/TopoSort.h:20: In file included from /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/topological_sort.hpp:16: /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/depth_first_search.hpp:301:8: note: in instantiation of function template specialization 'boost::parameter::aux::empty_arg_list::operator[]&lt;boost::graph::keywords::tag::root_vertex, unsigned long const&gt;' requested here <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> arg_pack[_root_vertex | *vertices(g).first] </p> </blockquote> <p> In file included from /Users/bdoig/Dropbox/WData/TopoSort.mm:11: In file included from /Users/bdoig/Dropbox/WData/TopoSort.h:20: /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/topological_sort.hpp:65:5: note: in instantiation of function template specialization 'boost::depth_first_search&lt;boost::adjacency_list&lt;boost::listS, boost::vecS, boost::directedS, TopoVertexProperty, boost::no_property, boost::no_property, boost::listS&gt;, boost::topo_sort_visitor&lt;std::front_insert_iterator&lt;std::deque&lt;int, std::allocator&lt;int&gt; &gt; &gt; &gt;, boost::graph_visitor_t, boost::bgl_named_params&lt;int, boost::buffer_param_t, boost::no_property&gt; &gt;' requested here <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> depth_first_search(g, params.visitor(<a class="missing wiki">TopoVisitor</a>(result))); </p> </blockquote> <p> /Users/bdoig/Documents/Projects/boost_1_43_0/boost/graph/topological_sort.hpp:71:5: note: in instantiation of function template specialization 'boost::topological_sort&lt;boost::adjacency_list&lt;boost::listS, boost::vecS, boost::directedS, TopoVertexProperty, boost::no_property, boost::no_property, boost::listS&gt;, std::front_insert_iterator&lt;std::deque&lt;int, std::allocator&lt;int&gt; &gt; &gt;, int, boost::buffer_param_t, boost::no_property&gt;' requested here <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> topological_sort(g, result, </p> </blockquote> <p> /Users/bdoig/Dropbox/WData/TopoSort.mm:20:3: note: in instantiation of function template specialization 'boost::topological_sort&lt;boost::adjacency_list&lt;boost::listS, boost::vecS, boost::directedS, TopoVertexProperty, boost::no_property, boost::no_property, boost::listS&gt;, std::front_insert_iterator&lt;std::deque&lt;int, std::allocator&lt;int&gt; &gt; &gt; &gt;' requested here <a class="changeset" href="https://svn.boost.org/trac10/changeset/2" title="Add Boost Disclaimer">[2]</a> </p> <blockquote> <p> boost::topological_sort(vectorList, std::front_inserter(topo_order)); </p> </blockquote> <p> 3 warnings generated. </p> en-us /htdocs/site/boost.png https://svn.boost.org/trac10/ticket/4528 Trac 1.4.3 Jeremiah Willcock Wed, 11 Aug 2010 19:00:58 GMT https://svn.boost.org/trac10/ticket/4528#comment:1 https://svn.boost.org/trac10/ticket/4528#comment:1 <ul> <li><strong>owner</strong> changed from <span class="trac-author">Andrew Sutton</span> to <span class="trac-author">Daniel Wallin</span> </li> <li><strong>component</strong> <span class="trac-field-old">graph</span> → <span class="trac-field-new">parameter</span> </li> </ul> <p> This looks like a Boost.Parameter issue, not a BGL one. The code mentioned in the error message (line 127 of <code>boost/parameter/aux_/arg_list.hpp</code>) does return a reference to a parameter passed in by copy. </p> Ticket