> and doesn't try to abstract things. The C standard is a description of an abstract machine. You get UB and unexpected miscompilations, because the optimizer

> and doesn't try to abstract things. The C standard is a description of an abstract machine. You get UB and unexpected miscompilations, because the optimizer is not evaluating how your code runs on the machine you're compiling for, but simulates running your code on the weirdly abstract C machine, one that can't overflow signed integers. And C abstracts away almost everything about stack, stack frames, and all the complexities of memory and cache hierarchies. They are abstracted to be uniform linear address space.