question about the condition removal he's lamenting his code would have gotten a... | Hacker News

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		avereveard on Nov 28, 2022 \| parent \| context \| favorite \| on: GCC undefined behaviors are getting wild question about the condition removal he's lamenting his code would have gotten an overflow at int32_t i = x * 0x1ff / 0xffff; where it not optimized away so it seems gcc is maintaining the code behaviour, only reporting a wrong debug line for it due code being shifted around.

shultays on Nov 28, 2022 [–]

the part that was optimized away is `i >= 0` check. Which can't happen because x >= 0 already holds true

avereveard on Nov 28, 2022 | [–]

it also moves the division around

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