> not obvious at the level that the optimizations are taking place Hmm...then it's up to the optimisers to up their game. Optimisation is supposed to be behav

> not obvious at the level that the optimizations are taking place Hmm...then it's up to the optimisers to up their game. Optimisation is supposed to be behaviour-preserving. Arguing that almost all real-world programs invoke UB and therefore don't have well-defined behaviour (by the standard as currently interpreted) is a bit of a cop-out.