> P.S. As always, Fabian Giesen's description of why compilers exploit signed overflow is a must-read: https://gist.github.com/rygorous/e0f055bfb74e3d5f0af20690

> P.S. As always, Fabian Giesen's description of why compilers exploit signed overflow is a must-read: https://gist.github.com/rygorous/e0f055bfb74e3d5f0af20690759.. https://gist.github.com/rygorous/e0f055bfb74e3d5f0af20690759.... What's missing from this is the only data point that matters: what's the slow-down on large programs if you are forced to compile without taking advantage of signed overflow UB? If you're breaking the language to get perf, then it's not enough to show that an optimization is possible. You also have to show that it has a net effect, outside of the microbenchmark you cherrypicked.