>>> A more ambitious goal, IMO, would be to understand what is the problem
>>> with doing every conversion of MSYS paths to native w32 format with
>>> "pwd -W", so that the pattern-matching technique could be entirely
>>> replaced with that simpler and more elegant one.
>>
>> That's a possibility, but note that "pwd -W" requires that you cd into
>> the directory first, which might be a problem in some rare cases.
>>
>> Also msys_lisppath_to_w32 works on PATH-style directory lists, not on
>> single directories, and some of those directories might not exist, or
>> include %emacs_dir%, which will cause pwd to fail.
>>
>> If these difficulties can be overcome, I have nothing against using
>> "pwd -W".
>
> I'm attaching a patch that works for me, and I think fulfills the
> above requirements.
>
> It makes _all_ translations of paths to native MS-Windows format using
> the "pwd -W" feature of the MSYS shell, which I think is the only
> reliable way of doing such translations.

I'm attaching a second version of the patch, with documentation
improvements and minor fixes to the 'msys-to-w32' script.

-- 
Dani Moncayo