fix: make the optional-plain-compare leak case print its peak, not its checksum - #808
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…s checksum The gate contract is that a case prints peak_kb() and nothing else; the case from #807 printed its hit counter instead, so the "growth" the gate compared was 800k*3 - 200k*3 = 1,800,000 — the difference of two checksums, not two peaks — and main went red on a case that does not leak. ## what was tested - the gate's own measure sequence against the rebuilt case: PITH_LEAK_ROUNDS=200000 -> 2616 kb, 800000 -> 2656 kb, growth 40 kb against the 2048 kb limit
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The leak gate's contract (documented in tests/leaks/leakprobe.pith) is that a case prints
peak_kb()and nothing else — the harness runs it at two round counts and compares the two numbers. The case added in #807 printed its hit counter instead, so the gate compared checksums: 800k rounds × 3 hits minus 200k × 3 = exactly the "grew 1800000kb" that turned main red. The compare shapes themselves do not leak.This aligns the case's main with the other cases: accumulate a checksum so the loop cannot be optimized away, guard it behind an impossible branch, print
probe.peak_kb().what was tested
PITH_LEAK_ROUNDS=200000→ 2616 kb peak,800000→ 2656 kb peak, growth 40 kb against the 2048 kb limit