https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119568
--- Comment #1 from Georg-Johann Lay <gjl at gcc dot gnu.org> --- So the ICE occurs with checking enabled, and otherwise it goes into hog mode: gcc_checking_assert (GET_MODE_CLASS (from_mode) == GET_MODE_CLASS (to_mode) && from_mode < to_mode);