Re: Make check on FreeBSD 10.x - Intel
Holger Freyther <[email protected]>
| Newsgroups | gmane.comp.lang.smalltalk.gnu.general |
|---|---|
| Message-ID | <[email protected]> |
> On 22 May 2015, at 04:00, nicolas cellier <[email protected]> wrote: > > That's exactly it. Overflow is undefined behavior. > The C compiler has a license to ignore undefined behavior because you are > not suppose to rely on it. Yes, but I couldn’t cite the relevant specification but you did in your blog post. I had pointed Esteban to use “-fsanitize=undefined” in the PharoVM. E.g. there are more issues with bitShift: in Pharo. > And see a fix in > http://smallissimo.blogspot.fr/2015/04/removing-ub-in-bytecodeprimmultiply.html. oh, I think my preference is to go with __builtin_mul_overflow (or for clang the smull variant as it can’t derive the types itself). The benefit of these routines is that one passes plenty of semantics that the compiler can generate efficient code. thanks for hanging out here and commenting! holger _______________________________________________ help-smalltalk mailing list [email protected] https://lists.gnu.org/mailman/listinfo/help-smalltalk