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The provenance memory model for C

(gustedt.wordpress.com)
224 points HexDecOctBin | 1 comments | 30 Jun 25 09:25 UTC | HN request time: 0.413s | source
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gavinray ◴[30 Jun 25 12:25 UTC] No.44422412[source]▶
Also of interest to folks looking at this might be TySan, the recently-merged LLVM Type-Based Aliasing sanitizer:

https://clang.llvm.org/docs/TypeSanitizer.html

https://www.phoronix.com/news/LLVM-Merge-TySan-Type-Sanitize...

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aengelke ◴[30 Jun 25 18:38 UTC] No.44426467[source]▶
It's probably worth noting that TySan currently only catches aliasing violations that LLVM would be able to exploit. For some types, e.g. unions, Clang doesn't emit accurate type-based aliasing information and therefore TySan won't catch these.
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1. flohofwoe ◴[30 Jun 25 22:27 UTC] No.44428607[source]▶
Which is fine I think, considering that union type punning is legal in C (and even in C++ where union type punning is UB I have never seen it break - theoretically it might of course).