[Bug other/91879] --with-build-sysroot doesn't work as expected

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91879

--- Comment #15 from Jonathan Wakely <redi at gcc dot gnu.org> ---
For the record, this has moved to
https://gcc.gnu.org/ml/gcc-help/2019-10/msg00002.html