&gt; Most compilers I know of do register allocation better than nearly all humans where optimization is important.<p>Nowadays yes, you are forgetting C has 40 years of research into compiler optimization.<p>We could easily beat the register allocator in the 90&#x27;s with Assembly coding, specially in x86.<p>There is a quote from a famous woman in compiler research from the mid-80&#x27;s, where she claims C semantics have thrown the optimization research back to the dinosaur age.<p>Sadly I cannot find it, as I don&#x27;t remember the exact words.<p>&gt; Aliasing is a problem, but I don&#x27;t think it&#x27;s strictly inherent to C.<p>Most languages have stricter semantics for aliasing and do not decay arrays into pointers.<p>Also they tend to have better type information, which can help the optimizer.