[PATCH v3] Handle Python 3.11 deprecation of PySys_SetPath and Py_SetProgramName

[Simon Marchi]

> @@ -1849,6 +1855,24 @@ show_python_dont_write_bytecode (struct ui_file *file, int from_tty,
>  		value);
>  }
>  
> +/* Return value to assign to PyConfig.write_bytecode or, when
> +   negated (via !), Py_DontWriteBytecodeFlag.  Py_DontWriteBytecodeFlag
> +   is deprecated in Python 3.12.  */
> +
> +static int
> +python_write_bytecode ()
> +{
> +  int wbc = 0;
> +
> +  if (python_dont_write_bytecode == AUTO_BOOLEAN_AUTO)
> +    wbc = (!python_ignore_environment
> +	    && getenv ("PYTHONDONTWRITEBYTECODE") != nullptr) ? 0 : 1;

I think it predates your patch (so, orthogonal), but the Python doc says:

  If this is set to a non-empty string, Python won’t try to write .pyc
  files on the import of source modules.

So I think we would need a "non-empty string" check here?

Simon