https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82686
--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #3)
> --enable-objc-gc requires you to provide boehm-gc yourself now. Quoting the
> installation instructions:
>
> @item --enable-objc-gc
> Specify that an additional variant of the GNU Objective-C runtime library
> is built, using an external build of the Boehm-Demers-Weiser garbage
> collector (@uref{http://www.hboehm.info/gc/}). This library needs to be
> available for each multilib variant,
^^^^^^^^^^^^^^^^^^^^^^^^^
Did you do that?
