https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109565
--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Frank Heckenbach from comment #2) > Maybe technically correct, but not useful to the user. Agreed, but you asked for it with that option. > The user's code doesn't involve pointers at all. It makes two queries about > a span object. As the user, I don't even (and shouldn't have to) care > whether pointer wraparound can occur in valid code on the given platform. (I > don't think so on Linux, but I'm not even sure.) So you shouldn't have to care about begin(c) < end(c) either, it has to be true. But you asked the compiler to give a warning if it relies on that assumption. > So if it can't validly occur, GCC can assume it doesn't, Right, it does assume that here, but you *specifically* asked to get a warning when it assumes that. > but won't need to > warn. You told it to warn! > Note that https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html doesn't > even mention pointers (let alone objects such as span) for -Wstrict-overflow. You're comparing std::span iterators, and those iterators are pointers.
