[MacPorts] #67742: PothosFlow: builds fail across-the-board: undefined symbols related to libcxx: allocator<>, basic_string<>, etc

[MacPorts]

#67742: PothosFlow: builds fail across-the-board: undefined symbols related to
libcxx: allocator<>, basic_string<>, etc
---------------------+------------------------
 Reporter:  mascguy  |      Owner:  ra1nb0w
     Type:  defect   |     Status:  assigned
 Priority:  Normal   |  Milestone:
Component:  ports    |    Version:  2.8.1
 Keywords:           |       Port:  PothosFlow
---------------------+------------------------
 Some notable examples - albeit only a subset - are:

 {{{
 Undefined symbols for architecture x86_64:
   "Poco::Environment::set(std::__1::basic_string<char,
 std::__1::char_traits<char>, std::__1::allocator<char> > const&,
 std::__1::basic_string<char, std::__1::char_traits<char>,
 std::__1::allocator<char> > const&)", referenced from:
       MyScopedSyslogListener::MyScopedSyslogListener() in PothosFlow.cpp.o

   "Poco::DateTimeFormatter::append(std::__1::basic_string<char,
 std::__1::char_traits<char>, std::__1::allocator<char> >&, Poco::DateTime
 const&, std::__1::basic_string<char, std::__1::char_traits<char>,
 std::__1::allocator<char> > const&, int)", referenced from:
       LoggerDisplay::handleLogMessage(Poco::Message const&) in
 LoggerDisplay.cpp.o

   "Poco::Net::SocketAddress::SocketAddress(std::__1::basic_string<char,
 std::__1::char_traits<char>, std::__1::allocator<char> > const&,
 std::__1::basic_string<char, std::__1::char_traits<char>,
 std::__1::allocator<char> > const&)", referenced from:
       EnvironmentEval::makeEnvironment() in EnvironmentEval.cpp.o

   "Poco::URI::URI(std::__1::basic_string<char,
 std::__1::char_traits<char>, std::__1::allocator<char> > const&)",
 referenced from:
       EnvironmentEval::makeEnvironment() in EnvironmentEval.cpp.o

   "Poco::Logger::get(std::__1::basic_string<char,
 std::__1::char_traits<char>, std::__1::allocator<char> > const&)",
 referenced from:
       myQLogHandler(QtMsgType, QMessageLogContext const&, QString const&)
 in PothosFlow.cpp.o

 [...etc, etc...]
 }}}

 Full log attached, for 10.10 buildbot. Though all appear to be similar.

-- 
Ticket URL: <https://trac.macports.org/ticket/67742>
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