https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90440
--- Comment #9 from Jonathan Wakely <redi at gcc dot gnu.org> --- Any check I add to libstdc++ now isn't going to help the 8.3.0 and 9.1.0 releases anyway, so a workaround (like using Solaris ln, or passing LN_S="cp -pR" to make) will still be needed for them.
