[Bug c++/98386] C++20 module: file exists failure and success happen alternatively for windows.

[unlvsur at live dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98386

--- Comment #9 from cqwrteur <unlvsur at live dot com> ---
(In reply to Nathan Sidwell from comment #7)
> Please take your diatribes to /dev/null.  Are you able to test the patch?

fixed confirm