Folding constants for floats

Hi, I'm cutting my teeth on some constant folding for floats in the cmm. I have a question regarding the ticket I'm tackling: Should floats be folded with infinite precision (and later truncated to the platform float size) -- most useful/accurate, or folded with the platform precision, i.e. double, losing accuracy but keeping consistent behaviour with -O0 -- most "correct"? I would prefer the first case because it's *much* easier to implement than the second, and it'll probably rot less. Regards.