These are just what it says: guidelines. When reviewing code, this is the vague problem space of issues to watch for. Every guideline may have exceptions, for author and reviewer to discuss and come to an agreement on.
- Does the code compile?
- Have unavoidable warnings been suppressed and explained in comments?
- Does the code have passing tests?
- Do the unit tests actually test all of the business logic, including edge cases?
- Does the code accomplish the business requirements (or fix the bug)? Does it only accomplish the requirements (no extra functionality)?