[clang] [Clang] Overflow Idiom Exclusions (PR #100272)

[Vitaly Buka via cfe-commits]

vitalybuka wrote:


> Right, unsigned overflow is well-defined. This isn't about the semantics of "undefined-ness". We want the unsigned sanitizer ON but some of the things it reports are noisy -- that's what this PR is about

"Idiom" seems to vague to me. kernel has own opinion on what is idem, other users may have a different.

Also so far we were able to avoid behavior tweaking flags in UBSAN. like `-fno-sanitize-overflow-idioms` (e.g. we have them in Asan). In UBSAN we were able to express as sets of checks. It would be nice to continue these way.

WDYT on splitting existing checks into smaller checks with verbose naming?

https://github.com/llvm/llvm-project/pull/100272