使用pip 安装第三方库，前面在升级pip（使用python.exe -m pip install --upgrade pip）也出现如下错误：
ERROR: Command errored out with exit status 1:
command: 'd:\python_3_7_6\python.exe' 'C:\Users\xxxXXXXoooOOOO\AppData\Roaming\Python\Python37\site-packages\pip\_vendor\pep517\_in_process.py' get_requires_for_build_wheel 'C:\Users\xxxXXXXoooOOOO\AppData\Local\Temp\tmpnuowj59l'
cwd: C:\Users\xxxXXXXoooOOOO\AppData\Local\Temp\pip-install-x1eu6x5h\pycryptodome
Complete output (30 lines):
Testing support for clang
Traceback (most recent call last):
File "C:\Users\xxxXXXXoooOOOO\AppData\Roaming\Python\Python37\site-packages\pip\_vendor\pep517\_in_process.py", line 207, in <module>
main()
File "C:\Users\xxxXXXXoooOOOO\AppData\Roaming\Python\Python37\site-packages\pip\_vendor\pep517\_in_process.py", line 197, in main
json_out['return_val'] = hook(**hook_input['kwargs'])
File "C:\Users\xxxXXXXoooOOOO\AppData\Roaming\Python\Python37\site-packages\pip\_vendor\pep517\_in_process.py", line 54, in get_requires_for_build_wheel
return hook(config_settings)
File "C:\Users\xxxXXXXoooOOOO\AppData\Local\Temp\pip-build-env-k8jgz0lh\overlay\Lib\site-packages\setuptools\build_meta.py", line 341, in get_requires_for_build_wheel
return self._get_build_requires(config_settings, requirements=['wheel'])
File "C:\Users\xxxXXXXoooOOOO\AppData\Local\Temp\pip-build-env-k8jgz0lh\overlay\Lib\site-packages\setuptools\build_meta.py", line 323, in _get_build_requires
self.run_setup()
File "C:\Users\xxxXXXXoooOOOO\AppData\Local\Temp\pip-build-env-k8jgz0lh\overlay\Lib\site-packages\setuptools\build_meta.py", line 338, in run_setup
exec(code, locals())
File "<string>", line 490, in <module>
File "C:\Users\xxxXXXXoooOOOO\AppData\Local\Temp\pip-install-x1eu6x5h\pycryptodome\compiler_opt.py", line 333, in set_compiler_options
clang = compiler_is_clang()
File "C:\Users\xxxXXXXoooOOOO\AppData\Local\Temp\pip-install-x1eu6x5h\pycryptodome\compiler_opt.py", line 257, in compiler_is_clang
return test_compilation(source, msg="clang")
File "C:\Users\xxxXXXXoooOOOO\AppData\Local\Temp\pip-install-x1eu6x5h\pycryptodome\compiler_opt.py", line 82, in test_compilation
解决办法：
到 C:\Users\用户名\AppData\Roaming下删除 Python文件夹
到 C:\Users\ppdyh\AppData\Local\Temp 下输出 pip开头的文件夹
