[Bug libstdc++/111244] std::filesystem::path encoding mismatches locale on Windows

["thiago at kde dot org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111244

--- Comment #5 from Thiago Macieira <thiago at kde dot org> ---
(In reply to Jonathan Wakely from comment #3)
> Somebody else will have to fix this, I've already wasted too much of my life
> making std:: filesystem (mostly) work on Windows.

Same here.

(In reply to Costas Argyris from comment #4)
> I'm wondering if it will work after embedding a UTF-8 manifest into your
> a.out executable, as described here:
> 
> https://learn.microsoft.com/en-us/windows/apps/design/globalizing/use-utf8-
> code-page

I can't embed a UTF-8 manifest in my DLL and much less in my .a. As a library
writer (I'm the QtCore maintainer), that's out of my hands - it is an
application decision.

If GCC+Binutils team wants to enforce that for the future, be my guest. I'd
support your decision; I think it's high time this happened. But I'm sure there
would be a lot of push-back from people who can't do that because their
existing Windows applications rely on the legacy encodings or those who deploy
to Windows versions that didn't have such support. I have a vague memory of
discussing this in the Qt development mailing list, but can't find it.

A softer approach is for std::filesystem to declare that it only supports
UTF-8-manifested applications (closing this bug as WONTFIX /
working-as-designed). I'd again support your decision and will simply pass the
requirement along to my users.