https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103655
--- Comment #1 from Jiang An <de34 at live dot cn> --- It seems that MS implemented the "x" mode in 2020: https://github.com/MicrosoftDocs/cpp-docs/commit/3e0701d935614423e1f09a6712cb5b5e28c43022#diff-be5df6fa41d451f0736c5cd8d863fb3bccfd2b49fbd6b0f7f5de6c07c87700ac So the alternative methods should be restricted to old OSes.
