Guaranteed 2 complement arithmetic for signed integers was recently added to C++. Wrap around is still UB though because apparently caused regressions in some s

Guaranteed 2 complement arithmetic for signed integers was recently added to C++. Wrap around is still UB though because apparently caused regressions in some significant code bases. Guaranteed order of evaluation of arguments almost made it into the standard, but because of regressions, we didn't quite get the full benefits; for example: i = i++ + 2; is now fully defined, while this: f(++i, ++i); is no longer UB, but implementation defined. Ideally for every UB taken away we would get one or more pragmas to get the optimization back like ivdep. The issue is that that doesn't help old code bases.