john.brawn added inline comments.
================ Comment at: clang/include/clang/Basic/Builtins.def:1409 -LIBBUILTIN(round, "dd", "fnc", "math.h", ALL_LANGUAGES) -LIBBUILTIN(roundf, "ff", "fnc", "math.h", ALL_LANGUAGES) -LIBBUILTIN(roundl, "LdLd", "fnc", "math.h", ALL_LANGUAGES) +LIBBUILTIN(round, "dd", "fng", "math.h", ALL_LANGUAGES) +LIBBUILTIN(roundf, "ff", "fng", "math.h", ALL_LANGUAGES) ---------------- scanon wrote: > `round` is just like `trunc` or `floor` or `ceil`, and should be "fnc" if > they are. I think they all should be the same, but I'm note sure if they should all be "fnc" or "fng". Looking at the C17 standard, in section F.10.6 (IEE754/IEC60559 behaviour of nearest integer functions) round, trunc, floor, and ceil are all described in the same way: "The xyz functions may, but are not required to, raise the "inexact" floating-point exception for finite non-integer arguments". I don't know if our policy should be "These functions may raise an exception, therefore we should assume they do and treat that as a side-effect", or "These functions are not required to raise an exception, therefore a program can't rely on it and so we don't need to treat it as a side-effect". Looking at implementations of these functions, it looks like GNU libm doesn't raise inexact, but the bionic libm does. I think I'm leaning towards marking all of them as "fng" as it's the more cautious of the two. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D129231/new/ https://reviews.llvm.org/D129231 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
