> On Sep 15, 2023, at 8:41 AM, Arsen Arsenović <ar...@aarsen.me> wrote: > > > Qing Zhao <qing.z...@oracle.com> writes: > >> Even though unsigned integer overflow is well defined, it might be >> unintentional, shall we warn user about this? > > This would be better addressed by providing operators or functions that > do overflow checking in the language, so that they can be explicitly > used where overflow is unexpected.
Yes, that will be very helpful to prevent unexpected overflow in the program in general. However, this will mainly benefit new codes. For the existing C codes, especially large applications, we still need to identify all the places Where the overflow is unexpected, and fix them. One good example is linux kernel. > One could easily imagine a scenario > where overflow is not expected in some region of code but is in the > larger application. Yes, that’s exactly the same situation Linux kernel faces now, the unexpected Overflow and expected wrap-around are mixed together inside one module. It’s hard to detect the unexpected overflow under such situation based on the current GCC. Thanks. Qing > -- > Arsen Arsenović
