Thank you for your reply. I got solution from Problems with building CPython - #4 by Thoufak. Actually, there is really something wrong with the downloaded source code of Python 3.9.5. I modified the following files according to bpo-45022: Pin current libffi build to fixed version in preparation f… · python/cpython@399cd46 · GitHub, and it works.
- PCbuild/get_externals.bat
- PCbuild/prepare_libffi.bat
- PCbuild/python.props