3.11 Regression, Py_Initialize; Fatal Python error: init_fs_encoding: failed to get the Python codec of the filesystem encoding

Bug report

Build and run the following program;

  #include <Python.h>
  
  int main(int argc, char* argv[])
  {
    Py_Initialize();
    return 0;
  }

The resulting executable runs fine when executed against the installed C:\Program Files\Python311\python311.dll

Executing against python311.dll copied to some other folder (C:\Windows\System32 for instance) results in;

Fatal Python error: init_fs_encoding: failed to get the Python codec of the filesystem encoding
Python runtime state: core initialized
ModuleNotFoundError: No module named 'encodings'

Current thread 0x0000333c (most recent call first):
  <no Python frame>

When also C:\Program Files\Python311\Lib\encodings is copied then the executable runs fine again.

This is not the case with Python versions prior to 3.11. The only thing needed to run Python embedded for versions below 3.11 is the appropriate pythonXXX.dll

Your environment

• CPython versions tested on:
  Python 3.11.0 (main, Oct 24 2022, 18:26:48) [MSC v.1933 64 bit (AMD64)] on win32
• Operating system and architecture:
  Edition Windows 11 Pro
  Version 21H2
  Installed on ‎11/‎24/‎2021
  OS build 22000.1098
  Experience Windows Feature Experience Pack 1000.22000.1098.0
• Compiler used:
  Microsoft Visual Studio Community 2022
  Version 17.3.6
  VisualStudio.17.Release/17.3.6+32929.385
  Microsoft .NET Framework
  Version 4.8.04161
  Installed Version: Community
  Visual C++ 2022 00482-90000-00000-AA258
  Microsoft Visual C++ 2022

從使用 Py_Initialize 和 Python.h 的 C 程式開始，在 Windows 11 上使用 Python 3.11 重現該行為。比較使用已安裝的 python311.dll、複製的 DLL 以及較早 Python 版本時的執行結果，接著調查初始化如何定位 Lib/encodings。當複製的 Python 3.11 DLL 無需另外複製 encodings 目錄即可完成初始化時，即視為完成。