IRC channel logs

<stikonas>argh, it looks like hex2_word.c in one place deliberately relies on 32-bit unsigned integer overflow

<stikonas>which goes wrong with 64 bit registers

<stikonas>well, should be easy to fix..

<stikonas>or at least easy to fix in hex2...

<stikonas>hex1 is a bit more annoying to fix because it would mean fixing hex1.hex0 code but I guess we don't have to fix hex1

<Hagfish>that's a great find

<Hagfish>is integer overflow undefined behaviour, that could be caught by a static analyser?

<stikonas>Hagfish: no, unsigned overflow is not undefined

<stikonas>also in high level languages (e.g. C++), unsigned overflow is well defined operation

<stikonas>only signed overflow is undefined

<stikonas>and oriansj used it intentionally I think

<stikonas>because to get the right result you have to use overflow there

<Hagfish>that's really insightful, thank you

2021-09-19.log