net/xmlrpc-c-devel port with GCC 4.8

/usr/local/bin/g++48 -o test   test.o base64.o registry.o server_abyss.o server_pstream.o tools.o value.o xml.o testclient.o /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/src/cpp/libxmlrpc_server_abyss++.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/src/cpp/libxmlrpc_server_pstream++.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/src/cpp/libxmlrpc_server++.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/src/cpp/libxmlrpc_client++.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/src/libxmlrpc_client.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/src/cpp/libxmlrpc++.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/src/cpp/libxmlrpc_cpp.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/src/libxmlrpc_server_abyss.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/src/libxmlrpc_server.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/src/libxmlrpc.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/lib/abyss/src/libxmlrpc_abyss.a /u
 s
r/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/src/cpp/libxmlrpc_packetsocket.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/lib/libutil/libxmlrpc_util.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/lib/expat/xmlparse/libxmlrpc_xmlparse.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/lib/expat/xmltok/libxmlrpc_xmltok.a   -pthread  /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/src/libxmlrpc_client.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/src/libxmlrpc.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/lib/expat/xmlparse/libxmlrpc_xmlparse.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/lib/expat/xmltok/libxmlrpc_xmltok.a /usr/ports/net/xmlrpc-c-devel/work/xmlrpc-c-1.32.99/lib/libutil/libxmlrpc_util.a  -L/usr/local/lib -lcurl -Wl,-rpath=/usr/lib:/usr/local/lib -L/usr/local/lib -lssh2 -lssl -lcrypto -lz -lssh2 -L/usr/local/lib -lwwwxml -lxmltok -lxmlparse -lwwwzip -lwwwssl -lwwwinit -lwwwapp -lwwwhtml -lwwwtelnet -lwwwnews -lwwwhttp -lww
 w
mime -lwwwgopher -lwwwftp -lwwwfile -lwwwdir -lwwwcache -lwwwstream -lwwwmux -lwwwtrans -lwwwcore -lwwwutils -lmd5 -lz -L/usr/lib -lssl -lcrypto
[...]
/usr/local/lib/gcc48/include/c++/bits/locale_facets.h:869: undefined reference to `std::ctype<char>::_M_widen_init() const'
[...]
/usr/local/lib/gcc48/include/c++/bits/stl_list.h:1550: undefined reference to `std::__detail::_List_node_base::_M_hook(std::__detail::_List_node_base*)'
[...]

I worked around this by adding "/usr/local/lib/gcc48/libstdc++.so" to the make-rule. Weird. Why does this work? Should it?