4 ms·

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.htm

• aengelke 1y ago
  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.
  • flohofwoe 1y ago
    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).
• uecker 1y ago
  The problem might be that Clang does not even implement type-based aliasing correctly. So I assume it checks its broken rules, instead of the one specified in the C standard.