https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70594
--- Comment #40 from Jakub Jelinek <jakub at gcc dot gnu.org> --- So, some further printf debugging shows that the first difference is that in one of the possible_polymorphic_call_targets calls (which creates the node->order == 4151 __builtin_unreachable in one with -g2 only and not with -g2 -gtoggle, the first backtrace in #c38) there is a difference in the context->maybe_in_construction flag - with -g2 it is 0, with -g2 -gtoggle it is 1.
