-Ofast turns on optimizations that can break standard-conforming programs! That is a very different thing that turning on optimizations that might break non-st

-Ofast turns on optimizations that can break standard-conforming programs! That is a very different thing that turning on optimizations that might break non-standard-conforming programs! I think the idea of making it controlled by optimization flags is interesting, but you would need to formalize what the more "safe" variant of the language is if people are actually going to depend on it.