https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81733
--- Comment #1 from Iain Sandoe <iains at gcc dot gnu.org> --- Is this still current? The ld64 assert is most likely triggered by a 0-length FDE. That could be caused by confusion over the partitioning. I don't see this on 10.11.6 with my bootstrap setup, what version of ld64 / cctools / bootstrap compiler are you using?