[Bug middle-end/118758] [15 regression] ok code with -O2, but wrong code with -O3

[sjames at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118758

--- Comment #5 from Sam James <sjames at gcc dot gnu.org> ---
Then sometimes once cvise has cleaned up a bunch of crap, it's often obvious
what the problem is, but if not, I let it run to completion. Anyway, I'll
continue reducing here, of course.