https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120121
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> --- (In reply to Stefano from comment #2) > @Andrew Pinski: I can't follow. Did you see my second example with the > compilation error? They are semantically equivalent and both produce the > same assembly output. > > So, why is there an error produced in the second example? The warning is only takes into account one statement at a time. So in the second example there is an implict variable. This is by design of front-end warnings.