https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66801
--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> --- Ok, so the only code-gen difference possible is due to match.pd patterns applying/not applying because of the changed iteration order making lattice values final at different times. Thus I suspect a latent bug in a match.pd pattern. Which means to possibly "bisect" those? I'm now first trying to reproduce.
