https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65261
--- Comment #2 from Bill Schmidt <wschmidt at gcc dot gnu.org> --- Markus, yes, if adding that attribute clears up the messages for you, then I would agree with that solution. The code is working as designed, as use of unaligned vector loads and stores on POWER8 is preferable to the forced-alignment solution. Could you please verify and submit a patch? Thanks, Bill