https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120428
--- Comment #11 from Shawn Xu <shawn at shawnxu dot org> --- Since r15-3078-g6ea25c041964bf63014fcf7bb68fb1f5a0a4e123 mentions -mprefer-vector-width, I tried setting -mprefer-vector-width=256 for compilation. This leads to the same regression in 14.2, but not in 13.3.