https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97715
--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> --- It is not fixed, but it is removed from accessible_reg_set. The same way how e.g. MMX regs are removed from it if !TARGET_MMX or SSE registers if !TARGET_SSE. You shouldn't try to zero unaccessible registers either.
