> From: Andrew Pinski <[EMAIL PROTECTED]> >>>> (Without -fwrapv, integer overflow is undefined, and subsequent range >>>> checks can be optimized away, so that it might cause erroneous >>>> behavior.) >>> >>> - Since for all practical purposes most (if not all) target's use >>> 2's complement integer representations which naturally "wrap", might >>> it be simply best to presume that all do "wrap" by default, but allow >>> -fnowrapv to disable it if ever required by the odd target/language? >> >> Enabling -fwrapv disables quite a few optimizations on signed integer >> types in C code. OTOH, you should compile most real-world C code with >> -fwrapv anyway. See my security advisory on incorrect overflow >> checking in C; this is a rather widespread issue, even in new code. > > No they should be using -ftrapv instead which traps on overflow and then > make sure they are not trapping when testing.
- why? what language or who's code/target ever expects such a behavior?
