https://gcc.gnu.org/bugzilla/show_bug.cgi?id=39121
--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> --- (In reply to joe.carnuccio from comment #5) > Since using gcc -Os causes the correct execution, then "sequence point" does > not have anything to do with it. And you are wrong about that. -Os causes what you think is the correct execution but there are multiple interpretations of the code because there are not sequence points there.
