[libcxx-commits] [libcxx] [libc++][hardening] Categorize more 'valid-element-access' checks. (PR #71620)

[Louis Dionne via libcxx-commits]

https://github.com/ldionne requested changes to this pull request.

This mostly LGTM, but I'd like to add tests for the iterator operations at least. It's reasonable for some of the other utilities not to add a bunch of tests, but for e.g. `counted_iterator` I think it's sufficiently high-value that we should be adding assertion tests.

https://github.com/llvm/llvm-project/pull/71620