As I learn more about lifetime annotations (e.g. 'a), I realize the programmer could make a mistake in assigning these and there is no way for Rust to verify. Thus lifetimes annotations are inherently unsafe (uncheckable) code. The program could crash accessing memory that has already been freed, which can't happen with GC. Am I missing something?
On an unrelated issue, afaics Rust can't prevent the same genre of non-crashing "memory leaks" that GC suffers from.