LanguagesCEvidence
cp-regex-hot — measured, still hint
Status
hint. Wall-clock JSONL: cp-regex-hot.jsonl. Not corpus-triaged. The 2026-10-22 corpus verdict does not cover this slug. regexec is not matched.
Measurement
Both sides call regexec on id-2026. Before calls regcomp and regfree every iteration.
| role | case | median_ms | ops | ratio |
|---|---|---|---|---|
| after | compile once | 0.834 | 2000 | 1 |
| before | regcomp every iteration | 8.131 | 2000 | 9.749 |
This is the C sibling of the compile-once regular-expression rules. Default stays hint.
Unblock
Do not set the default to error from this file alone. Another input or a cold path can erase the difference. Corpus triage is still required before any default change.