[Bug libstdc++/77814] build fails trying to build eh_arm

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77814

--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Patch being testing now:
https://gcc.gnu.org/ml/gcc-patches/2016-10/msg00058.html