WebAssembly: qtwebsockets build failure on windows

agent:2019/08/13 19:33:14 build.go:215: em++ -c -O3 -std=c++11 -fvisibility=hidden -fvisibility-inlines-hidden -fno-exceptions -s ALLOW_MEMORY_GROWTH=1 -Wall -Wextra -Wdate-time -Winconsistent-missing-override -DQT_NO_LINKED_LIST -DQT_NO_FOREACH -DQT_NO_NARROWING_CONVERSIONS_IN_CONNECT -DQT_BUILD_WEBSOCKETS_LIB -DQT_BUILDING_QT -DQT_NO_CAST_TO_ASCII -DQT_ASCII_CAST_WARNINGS -DQT_MOC_COMPAT -DQT_USE_QSTRINGBUILDER -DQT_DEPRECATED_WARNINGS -DQT_DISABLE_DEPRECATED_BEFORE=0x050000 -DQT_DEPRECATED_WARNINGS_SINCE=0x060000 -DQT_NO_EXCEPTIONS -D_LARGEFILE64_SOURCE -D_LARGEFILE_SOURCE -DQT_NO_DEBUG -DQT_NETWORK_LIB -DQT_CORE_LIB -I. -I..\..\include -I..\..\include\QtWebSockets -I..\..\include\QtWebSockets\5.14.0 -I..\..\include\QtWebSockets\5.14.0\QtWebSockets -Ic:\Users\qt\work\install\include\QtCore\5.14.0 -Ic:\Users\qt\work\install\include\QtCore\5.14.0\QtCore -Ic:\Users\qt\work\install\include -Ic:\Users\qt\work\install\include\QtNetwork -Ic:\Users\qt\work\install\include\QtCore -I.moc -Ic:\Users\qt\work\install\mkspecs\wasm-emscripten -o .obj\qwebsocketdataprocessor.obj qwebsocketdataprocessor.cpp
agent:2019/08/13 19:33:15 build.go:215: em++ -c -O3 -std=c++11 -fvisibility=hidden -fvisibility-inlines-hidden -fno-exceptions -s ALLOW_MEMORY_GROWTH=1 -Wall -Wextra -Wdate-time -Winconsistent-missing-override -DQT_NO_LINKED_LIST -DQT_NO_FOREACH -DQT_NO_NARROWING_CONVERSIONS_IN_CONNECT -DQT_BUILD_WEBSOCKETS_LIB -DQT_BUILDING_QT -DQT_NO_CAST_TO_ASCII -DQT_ASCII_CAST_WARNINGS -DQT_MOC_COMPAT -DQT_USE_QSTRINGBUILDER -DQT_DEPRECATED_WARNINGS -DQT_DISABLE_DEPRECATED_BEFORE=0x050000 -DQT_DEPRECATED_WARNINGS_SINCE=0x060000 -DQT_NO_EXCEPTIONS -D_LARGEFILE64_SOURCE -D_LARGEFILE_SOURCE -DQT_NO_DEBUG -DQT_NETWORK_LIB -DQT_CORE_LIB -I. -I..\..\include -I..\..\include\QtWebSockets -I..\..\include\QtWebSockets\5.14.0 -I..\..\include\QtWebSockets\5.14.0\QtWebSockets -Ic:\Users\qt\work\install\include\QtCore\5.14.0 -Ic:\Users\qt\work\install\include\QtCore\5.14.0\QtCore -Ic:\Users\qt\work\install\include -Ic:\Users\qt\work\install\include\QtNetwork -Ic:\Users\qt\work\install\include\QtCore -I.moc -Ic:\Users\qt\work\install\mkspecs\wasm-emscripten -o .obj\qwebsocketcorsauthenticator.obj qwebsocketcorsauthenticator.cpp
agent:2019/08/13 19:33:16 build.go:215: qwebsockethandshakeresponse.cpp:165:80: error: too few template arguments for class template 'less'
agent:2019/08/13 19:33:16 build.go:215:                 listIntersection(supportedProtocols, request.protocols(), std::less<>());
agent:2019/08/13 19:33:16 build.go:215:                                                                                ^
agent:2019/08/13 19:33:16 build.go:215: C:\Utils\emsdk\emscripten-1.38.27\system\include\libcxx\__functional_base:51:29: note: template is declared here
agent:2019/08/13 19:33:16 build.go:215: struct _LIBCPP_TEMPLATE_VIS less : binary_function<_Tp, _Tp, bool>
agent:2019/08/13 19:33:16 build.go:215:                             ^
agent:2019/08/13 19:33:16 build.go:215: qwebsockethandshakeresponse.cpp:169:82: error: too few template arguments for class template 'less'
agent:2019/08/13 19:33:16 build.go:215:                 listIntersection(supportedExtensions, request.extensions(), std::less<>());
agent:2019/08/13 19:33:16 build.go:215:                                                                                  ^
agent:2019/08/13 19:33:16 build.go:215: C:\Utils\emsdk\emscripten-1.38.27\system\include\libcxx\__functional_base:51:29: note: template is declared here
agent:2019/08/13 19:33:16 build.go:215: struct _LIBCPP_TEMPLATE_VIS less : binary_function<_Tp, _Tp, bool>
agent:2019/08/13 19:33:16 build.go:215:                             ^
agent:2019/08/13 19:33:16 build.go:215: qwebsockethandshakeresponse.cpp:171:78: error: too few template arguments for class template 'greater'
agent:2019/08/13 19:33:16 build.go:215:                 listIntersection(supportedVersions, request.versions(), std::greater<>()); //sort in descending order
agent:2019/08/13 19:33:16 build.go:215:                                                                              ^
agent:2019/08/13 19:33:16 build.go:215: C:\Utils\emsdk\emscripten-1.38.27\system\include\libcxx\functional:720:29: note: template is declared here
agent:2019/08/13 19:33:16 build.go:215: struct _LIBCPP_TEMPLATE_VIS greater : binary_function<_Tp, _Tp, bool>
agent:2019/08/13 19:33:16 build.go:215:                             ^
agent:2019/08/13 19:33:16 build.go:215: 3 errors generated.
agent:2019/08/13 19:33:16 build.go:215: shared:ERROR: compiler frontend failed to generate LLVM bitcode, halting