--- Python-3.8.7/setup.py.orig 2020-12-26 07:15:03.663309900 +0100 +++ Python-3.8.7/setup.py 2020-12-26 07:51:28.765752400 +0100 @@ -892,7 +892,11 @@ depends=['testcapi_long.h'])) # Python Internal C API test module + macros = [] + if MS_WINDOWS: + macros.append(('PY3_DLLNAME', 'L"%s"' % sysconfig.get_config_var('DLLLIBRARY'))) self.add(Extension('_testinternalcapi', ['_testinternalcapi.c'], + define_macros=macros, extra_compile_args=['-DPy_BUILD_CORE_MODULE'])) # Python PEP-3118 (buffer protocol) test module