alt Hacker NewsPeople do crypto using floats these days?
Wow.
I mean I know djb managed at some point to coax an x86 CPU floating point unit to perform weird integer operations to speed up some of his algorithms, but I would never have expected people to use floats the "intended way" to implement crypto algorithms.
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Im not a security engineer at all and I have an instant gut reaction to floats in regular code. ”How big can this get? Is it deserialized? What arithmetic ops are happening? Any risk of rounding error propagation?” etc.
Now, I wouldn’t necessarily mean I deem it bad practice in security contexts since again, I don’t know. But if an expert doesn’t consider those things, I would be surprised (and a little scared).
Well, no. That's the bug. The fix is to "not do that", although one does wonder what the original author was smoking!
https://github.com/cloudflare/circl/commit/f7d2180d6a77cfb28...
So, in this case it wasn't correct to do so, but there is actually a current algorithm which uses floating point: Falcon (aka FN-DSA).
https://keymaterial.net/2026/05/13/so-you-want-to-deploy-fn-... talks about FN-DSA and has a section about how it's require to hand-implement floats to get constant-time operations.