I have downloaded and built Boost 1.64 on Windows by using the following 
command:

b2 --build-type=complete address-model=64 toolset=msvc stage
I added a user-config.jam file in my home directory to tell Boost where to find 
Python 3:

using python : 3.6 : c:\\anaconda3\\python ;
I am then trying to compile a small test project using boost::python and 
boost::numpy:

        #include <boost/python.hpp>
        #include <boost/python/numpy.hpp>

        namespace bp = boost::python;
        namespace np = boost::python::numpy;

        np::ndarray test_make_zeros(int rows, int cols)
        {
                return np::zeros(bp::make_tuple(rows, cols), 
np::dtype::get_builtin<float>());  
        }

        BOOST_PYTHON_MODULE(test_boost_python)
        {
                np::initialize();
                bp::def("test_make_zeros", test_make_zeros);
        }

I am using the following CMakeLists.txt file:

        cmake_minimum_required(VERSION 3.8)
        project(test_boost_python)

        set(BOOST_ROOT "C:/Boost-1.64")
        set(Boost_ADDITIONAL_VERSIONS 1.64)

        find_package(PythonLibs 3.6 REQUIRED)
        include_directories(${PYTHON_INCLUDE_DIRS})

        find_package(Boost REQUIRED COMPONENTS python3 numpy3)
        include_directories(${Boost_INCLUDE_DIRS})
        link_directories(${Boost_LIBRARY_DIRS})

        add_library(test_boost_python SHARED test_boost_python.cpp)
        set_target_properties(test_boost_python PROPERTIES PREFIX "" SUFFIX 
".pyd")
        set_target_properties(test_boost_python PROPERTIES DEFINE_SYMBOL 
"BOOST_ALL_NO_LIB")
        target_link_libraries(test_boost_python ${PYTHON_LIBRARIES} 
${Boost_LIBRARIES})

My boost::python library is given the name boost_python3-vc140-mt-1_64.lib and 
boost::numpy ends up as boost_numpy3-vc140-mt-1_64.lib when linking against 
Python 3.6.

I had to turn on BOOST_ALL_NO_LIB. If not, the compiler looks for 
boost_python-vc140-mt-1_64.lib boost_numpy-vc140-mt-1_64.lib (which is under 
the wrong name, with a missing number 3 after the library names - Is this a bug 
on Windows?)

For my test project, I now get the following linking error:

        test_boost_python.obj : error LNK2019: unresolved external symbol 
"class boost::python::numpy::dtype __cdecl 
boost::python::numpy::detail::get_float_dtype<32>(void)" 
(??$get_float_dtype@$0CA@@detail@numpy@python@boost@@YA?AVdtype@123@XZ) 
referenced in function "public: static class boost::python::numpy::dtype 
__cdecl boost::python::numpy::detail::builtin_dtype<float,0>::get(void)" 
(?get@?$builtin_dtype@M$0A@@detail@numpy@python@boost@@SA?AVdtype@345@XZ)

What may be the reason for this missing symbol and how should I go about to fix 
it?

-Øystein
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