[mbauman]

I don't think it should exist at all. It's such a crazy grab bag of code changes disguised as "optimizations" that it's completely impossible to reason about, even for folks that "don't care" about the exact floating point arithmetic.

It has global effects like those in TFA, and even locally you no longer know if a line or two of arithmetic will become more precise (e.g., by using higher precision intermediate results), less precise, or become complete gibberish (e.g., because it thinks it can prove you're now dividing by zero and thus can just return whatever it wants).