問題描述

一開始使用pyenv安裝了python 3.9.6版本之後，pyenv居然失靈了，切換不到任何版本去了，一氣之下，刪掉pyenv（rm -rf ~/.pyenv）直接原始碼安裝。

步驟如下：

1. 到官網https://www.python.org/downloads/下載最新的tar包

2. 解壓後執行：

    ./configure --prefix=/opt/python-3.9.6
    make
    make install
   

3. 安裝完成後，pip不能正常使用，即便是檢視已安裝包都會出現core dump

    $ python3 -V
    Python 3.9.6
    $ pip3 list
    Package    Version
    ---------- -------
    pip        21.1.3
    setuptools 56.0.0
    Segmentation fault (core dumped)
    $ python3 -m pip list
    Package    Version
    ---------- -------
    pip        21.1.3
    setuptools 56.0.0
    Segmentation fault (core dumped)
    
   

解決方法

找了半天沒有找到答案，最後只能硬著頭皮去除錯pip3的程式碼，結果發現跟SSL有關（後面會描述如何發現的，這裡先說解決方法）。

官網https://www.python.org/dev/peps/pep-0644/也說了要求OpenSSL 1.1.1及以上版本（“Require OpenSSL 1.1.1 or newer”），而我自己機器上的是1.1.0版本的。

$ openssl version
OpenSSL 1.1.0h-fips  27 Mar 2018

解決辦法：

1. 到OpenSSL官網https://www.openssl.org/source/下載1.1.1版本的tar包

2. 解壓後執行：

    ./config
    make
    make install
   

3. 安裝完成後，檢視OpenSSL版本報錯：

    $ openssl version
    openssl: /usr/lib64/libssl.so.1.1: version `OPENSSL_1_1_1' not found (required by openssl)
    openssl: /usr/lib64/libcrypto.so.1.1: version `OPENSSL_1_1_1' not found (required by openssl)
   

   解決辦法：

    export LD_LIBRARY_PATH=/usr/local/lib64    # 最好寫入 ~/.bashrc 或 /etc/profile 中去
    $ openssl version
    OpenSSL 1.1.1k  25 Mar 2021
    
   

4. 這個時候以為問題解決了，重新執行 pip3 list 仍然會出現 core dump，折騰了一天，差點都想放棄了，後來一想，python編譯時連結的還是原來的舊庫，所有需要重新編譯python。回到 python 原始碼解壓目錄執行：

    make distclean    # 把上一次編譯過程中留下的餘孽清理乾淨
    ./configure --prefix=/opt/python-3.9.6
    make
    make install
   

5. 完事後，再試，大功告成！

    $ pip3 list
    Package    Version
    ---------- -------
    pip        21.2.1
    setuptools 56.0.0
    $ python3 -m pip list
    Package    Version
    ---------- -------
    pip        21.2.1
    setuptools 56.0.0
    $ pip list
    Package    Version
    ---------- -------
    pip        21.2.1
    setuptools 56.0.0
   

分析過程

1. 網上搜答案，沒有雷同的，苦惱！

2. 想嘗試去除錯Core dump吧，即便執行了 ulimit -c unlimited ，也不會在當前目錄中生成 core file，最後發現 core file 在下面這個目錄，汗！

    /var/lib/systemd/coredump
   

3. 有了 core file，咋除錯？ 執行 gdb /opt/python-3.9.6/bin/pip3 core-file 根本就打印不出 backtrace 出來，因為 pip3 本身是個 python 文字檔案，而不是二進位制可執行程式。

4. 好吧，除錯 pip3 這個 python 檔案：

    $ python -m pdb /opt/python-3.9.6/bin/pip3 list
    > /opt/python-3.9.6/bin/pip3(3)<module>()
    -> import re
    (Pdb) b /opt/python-3.9.6/lib/python3.9/ssl.py:483
    Breakpoint 1 at /opt/python-3.9.6/lib/python3.9/ssl.py:483
    (Pdb) c
    Package    Version
    ---------- -------
    pip        21.1.3
    setuptools 56.0.0
    > /opt/python-3.9.6/lib/python3.9/ssl.py(483)__new__()
    -> self = _SSLContext.__new__(cls, protocol)
    (Pdb) where
      /opt/python-3.9.6/lib/python3.9/bdb.py(580)run()
    -> exec(cmd, globals, locals)
      <string>(1)<module>()
      /opt/python-3.9.6/bin/pip3(8)<module>()
    -> sys.exit(main())
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_internal/cli/main.py(71)main()
    -> return command.main(cmd_args)
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_internal/cli/base_command.py(104)main()
    -> return self._main(args)
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_internal/cli/base_command.py(221)_main()
    -> self.handle_pip_version_check(options)
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_internal/cli/req_command.py(147)handle_pip_version_check()
    -> pip_self_version_check(session, options)
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_internal/self_outdated_check.py(152)pip_self_version_check()
    -> best_candidate = finder.find_best_candidate("pip").best_candidate
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_internal/index/package_finder.py(879)find_best_candidate()
    -> candidates = self.find_all_candidates(project_name)
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_internal/index/package_finder.py(824)find_all_candidates()
    -> page_candidates = list(page_candidates_it)
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_internal/index/sources.py(134)page_candidates()
    -> yield from self._candidates_from_page(self._link)
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_internal/index/package_finder.py(783)process_project_url()
    -> html_page = self._link_collector.fetch_page(project_url)
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_internal/index/collector.py(512)fetch_page()
    -> return _get_html_page(location, session=self.session)
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_internal/index/collector.py(422)_get_html_page()
    -> resp = _get_html_response(url, session=session)
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_internal/index/collector.py(120)_get_html_response()
    -> resp = session.get(
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_vendor/requests/sessions.py(555)get()
    -> return self.request('GET', url, **kwargs)
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_internal/network/session.py(449)request()
    -> return super().request(method, url, *args, **kwargs)
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_vendor/requests/sessions.py(542)request()
    -> resp = self.send(prep, **send_kwargs)
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_vendor/requests/sessions.py(655)send()
    -> r = adapter.send(request, **kwargs)
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_vendor/cachecontrol/adapter.py(53)send()
    -> resp = super(CacheControlAdapter, self).send(request, **kw)
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_vendor/requests/adapters.py(439)send()
    -> resp = conn.urlopen(
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_vendor/urllib3/connectionpool.py(699)urlopen()
    -> httplib_response = self._make_request(
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_vendor/urllib3/connectionpool.py(382)_make_request()
    -> self._validate_conn(conn)
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_vendor/urllib3/connectionpool.py(1010)_validate_conn()
    -> conn.connect()
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_vendor/urllib3/connection.py(392)connect()
    -> self.ssl_context = create_urllib3_context(
      /opt/python-3.9.6/lib/python3.9/site-packages/pip/_vendor/urllib3/util/ssl_.py(281)create_urllib3_context()
    -> context = SSLContext(ssl_version or PROTOCOL_TLS)
    > /opt/python-3.9.6/lib/python3.9/ssl.py(483)__new__()
    -> self = _SSLContext.__new__(cls, protocol)    <=========== 這裡已經進不去了，core就出現在這一步，看名字就是跟SSL有關吧
    (Pdb) p cls
    <class 'ssl.SSLContext'>
    (Pdb) p protocol
    <_SSLMethod.PROTOCOL_TLS: 2>
    (Pdb) s
    Segmentation fault (core dumped)
   

5. 看到SSL立馬去搜 python +SSL 關鍵字，才發現官網的這個說明https://www.python.org/dev/peps/pep-0644/，也就有了去嘗試安裝 OpenSSL 1.1.1 的想法。

這一切的一切都源於本來想安裝 pypiwin32 這個包，想用它來分析windows系統日誌，windows上裝成功了，linux上沒有裝成功，然後以為是舊版本的問題去裝新版本，折騰了一天，燒死多少腦細胞，就搞個環境問題，不過，生命在於折騰嘛！