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Comment by ysofunny | Hacker News Reader

how about some floating point sizes?

then again, thinking about code with timestamps in float makes me scared

I once wrote a fuzzer for some code that serialized and deserialized a particular data structure that included a timestamp -- the complexity cannot be overstated.

Basically every possible edge case came up: floats can be infinity, negative infinity, negative zero, NaN, and even subnormal. The bulk of the problems occurred because we deserialized the float timestamp and proceeded to do unchecked math on it, then expected it to be a normal value.

What is the problem with subnormals? They're just numbers really close to zero

The way they are represented in binary is distinct, basically you need to add an additional edge case when you're decoding it.

I swear John Carmack said somewhere "Time should be a double that starts from 1 billion" or something, for games or VR or something.

Of course when I search on DDG I only get "wow the fast inverse square root"

This one? https://twitter.com/ID_AA_Carmack/status/418158611664097280

How!?

Not sure how mrmincent did it, but when I searched DDG, it didn't come up with anything. I then switched to Brave Search and it was in the middle of the first page, just past the fold. I specifically searched for:

  john carmack time double

I seeing a screenshot in a programming subreddit showing a financial institution storing monetary data as floats, so I wouldn't be surprised.

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