https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91275
--- Comment #1 from Lauri Kasanen <cand at gmx dot com> --- clang 7.0.0 outputs the expected values, aka the gcc -O0 ones, at all optimization levels. (it calls the builtin __builtin_altivec_crypto_vpmsumd, but no other changes)
