Must every sanity warning be zero?
From PDVerse PnR Interview Handbook, part of the pdVerse Mentor Guide
Short Answer
No — the goal isn't a warning count of zero, it's that every remaining warning has been actually looked at and understood, which is a very different bar. Each warning needs to be sorted into one of two buckets: a real defect that needs fixing, or a justified, intentional structure that happens to trigger the check — and that sorting decision has to be made explicitly, not assumed.
Technical Explanation
- A warning is really a request for engineering judgment, not an error demanding automatic suppression — treating every warning as something to silence just to get to zero is how real defects get waived away by accident.
- Whatever's left after triage needs a paper trail: named objects, supporting evidence, an owner who signed off on the waiver, an assessment of the risk it carries, and a review date so it doesn't get forgotten permanently.
- This is exactly the discipline that separates a rushed signoff from a defensible one — a reviewer six months later should be able to see why each remaining warning was accepted, not just that it was.
What To Check
- Warning sign: A team suppresses a warning ID globally or accepts a stable count without checking membership.
- Inspect: Keep at least two possible causes open, then use one named object and the active mode or scenario to separate them.
- Correct: Fix defects, record narrow waivers, rerun from the clean checkpoint, and compare both counts and object sets.
Command Checks & Actions
- get_message_info -warning_count: summarizes messages for triage
check_timing: finds missing or inconsistent timing setup
Run the commands in order. Each line answers a separate part of the check.
Healthy, Suspicious & Hard-stop Results
- Expected: No; each warning must be classified as a defect or justified intent with named objects, evidence, owner, risk, and review date.
- Stop before floorplanning when required logic or timing coverage is missing or unexplained.
Common Mistake
The Trap: Do not assume the check passed just because ICC2 continued. Fix or narrowly justify the named objects, then rerun the same command.
What The Interviewer Is Testing
Be ready to explain why this matters before floorplanning.
Follow-up Question & Model Response
Model response: “I would save the report, inspect one affected object in the correct block and scenario, and make or request this correction. ”
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