[Jweb_Guru]

> Right, but given that panicing was already allowable behavior, why was the new behavior chosen to be one likely to introduce subtle bugs?

Because casting to floats is not UB in the Rust spec, it's UB in LLVM. That's the whole reason this was an issue in the first place.

Now, Rust could have chosen to define the behavior to panic, but so far it's been a hard and fast rule in Rust that as casts do not panic. You would have to have a much better reason to change that then "well, it was UB before" since (1) nobody wanted it to be UB before, and (2) the actual implementation never panicked (and people absolutely rely on the fact that casts don't panic in unsafe code).