https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81797
--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> --- Do you have the file $target/libstdc++-v3/include/stamp-bits-sup ?
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81797
--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> --- Do you have the file $target/libstdc++-v3/include/stamp-bits-sup ?