That is only possible if the optimization is wrong (rare), or the program alread... | Hacker News

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		rocqua on Oct 28, 2024 \| parent \| context \| favorite \| on: Optimizers need a rethink That is only possible if the optimization is wrong (rare), or the program already had undefined behavior (very common, because undefined behavior is very easy to trigger in C).

glitchc on Nov 1, 2024 [–]

I'll give an example: -ffast-math.

There's extensive literature out there on how fast-math changes the behaviour of code. I've been bitten by this a couple of times already.

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