> I've worked with firmware that only worked with -O0 and failed with -O2 But as we can see in this vuln, there's functionality that works in the normal case b

> I've worked with firmware that only worked with -O0 and failed with -O2 But as we can see in this vuln, there's functionality that works in the normal case but where important checks are elided, and compilers might decide not to do anything with a piece of undefined behaviour in one version but not in the next. Whether a piece of code works in -O2 doesn't prove it doesn't contain undefined behaviour.