[Bug libstdc++/103445] build failure for old versions of mingw32 (not mingw-w64)

[redi at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103445

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
How old is that? We generally only support building with recent versions that
are still supported by mingw.