Ancestors

Written by comex on 2025-01-22 at 02:06

“Clang will now more aggressively use undefined behavior on pointer addition overflow for optimization purposes.” https://github.com/llvm/llvm-project/commit/c2979c58d49b

A whole lot of non-exploitable bugs may become exploitable pretty soon.

=> More informations about this toot | More toots from comex@mas.to

Written by Andrew Zonenberg on 2025-01-22 at 02:08

@comex Why do compiler devs (and standards writers) keep doing this kind of thing? Does it really make non buggy code significantly faster?

=> More informations about this toot | More toots from azonenberg@ioc.exchange

Toot

Written by external quantum efficiency on 2025-01-22 at 22:48

@azonenberg @comex I don't know about this specific case, but commonly this kind of optimization allows the compiler to, for example, automatically vectorize a loop that's written in idiomatic source code style. So you can write the code looking readable, and the compiler turns it into avx512 that runs 20x faster than the baseline version.

=> More informations about this toot | More toots from eqe@aleph.land

Descendants