On 1/24/2013 10:02 AM, Jeffrey Walton wrote:
What I am not clear about is when an operation is deemed "undefined" or "implementation defined".
The compiler is free to assume that no arithmetic operation on signed integers results in overflow. It is allowed to take advantage of such assumptions in generating code (and it does so). You have no right to assume *anything* about the semantics of code that has an integer overflow (let alone make asssumptions about the generated code). This is truly undefined, not implementation defined, and if your program has such an overflow, you cannot assume ANYTHING about the generated code.
