Compile time error with intel 19.0.4.243

從 boost/operators.hpp 第 169 行和 libs/python/src/converter/registry.cpp 第 302 行附近開始，然後使用 Intel icpc 19.0.4.243 和所示的 C++11 命令重現該失敗。調查編譯器的 constexpr 診斷，並確立一項相容性變更或支援版本限制，使 Boost.Python 能夠完成編譯。

I suspect the compiler is at fault, but still:

intel-linux.compile.c++ bin.v2/libs/python/build/intel-linux/release/python-3.6/threading-multi/visibility-hidden/converter/registry.o
./boost/operators.hpp(169): error #3377: constexpr function return is non-constant
       friend BOOST_OPERATORS_CONSTEXPR bool operator!=(const T& x, const T& y) { return !static_cast<bool>(x == y); }
                                                                                         ^
          detected during instantiation of class "boost::operators_impl::equality_comparable1<T, B> [with T=boost::python::type_info, B=boost::operators_impl::operators_detail::empty_base<boost::python::type_
info>]" at line 302 of "libs/python/src/converter/registry.cpp"

compilation aborted for libs/python/src/converter/registry.cpp (code 2)

    "icpc" -c -xc++ -fvisibility-inlines-hidden -fPIC -m64 -pthread -fvisibility=hidden -w1 -inline-level=2 -O3 -ip -std=c++11 -DBOOST_ALL_NO_LIB=1 -DBOOST_PYTHON_SOURCE -DNDEBUG -I"." -I"/opt/software/occige
n/tools/intelpython3/2019.3/intelpython3/include/python3.6m"   -c -o "bin.v2/libs/python/build/intel-linux/release/python-3.6/threading-multi/visibility-hidden/converter/registry.o" "libs/python/src/converter
/registry.cpp"

...failed intel-linux.compile.c++ bin.v2/libs/python/build/intel-linux/release/python-3.6/threading-multi/visibility-hidden/converter/registry.o...

Thanks