https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101865
--- Comment #2 from Bill Schmidt <wschmidt at gcc dot gnu.org> --- The _ARCH_PWR8 predefine is conditioned on a flag that can be disabled by -mno-vsx or -mno-altivec. That is a Bad Thing. It appears (as David pointed out privately) that this problem is limited to _ARCH_PWR8, as the other _ARCH levels are using stable tests that can't be so easily disabled.
