FAILURE MAP
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FA-40856 / Heap invariants / Open access

Bucket pop clears occupancy only when the bucket becomes empty · case 01

The bounded priority bitset certificate reports an incorrect after pop.

Verified by executionVariant 1 · 7 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Bucket pop clears occupancy only when the bucket becomes empty.

THE FAILURE

Bucket pop clears occupancy only when the bucket becomes empty.

Unsuccessful approach: The local patch uses mask ^ (1<<p) if b else mask and still violates the stated relation.

Case contract

A bounded bucket priority queue certificate supplies occupancy mask and bucket lists for priorities 0..width-1. Report actual occupancy mask, least occupied priority, greatest occupied priority, mask-only ghost priorities, missing-mask priorities, and popped-bucket bit clearing after removing one first element from requested priority. Empty buckets are valid.

Why this case matters

This isolates an internal heap representation or priority-structure invariant using deterministic finite records.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(d):
    b=d['buckets']; mask=d['mask']; p=d['pop']; actual=sum(1<<i for i,x in enumerate(b) if x); remaining=max(0,len(b[p])-1) if b else 0
    return {'actual_mask': actual,
    'minimum': (actual & -actual).bit_length()-1 if actual else None,
    'maximum': actual.bit_length()-1 if actual else None,
    'ghosts': [i for i,x in enumerate(b) if mask&(1<<i) and not x],
    'missing': [i for i,x in enumerate(b) if x and not mask&(1<<i)],
    'after_pop': mask & ~(1<<p) if b else mask}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[({'buckets': [], 'mask': 0, 'pop': 0}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [['a']], 'mask': 1, 'pop': 0}, {'actual_mask': 1, 'minimum': 0, 'maximum': 0, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [[], ['a', 'b'], [], ['c']], 'mask': 10, 'pop': 1}, {'actual_mask': 10, 'minimum': 1, 'maximum': 3, 'ghosts': [], 'missing': [], 'after_pop': 10}), ({'buckets': [['a'], [], ['c']], 'mask': 3, 'pop': 0}, {'actual_mask': 5, 'minimum': 0, 'maximum': 2, 'ghosts': [1], 'missing': [2], 'after_pop': 2}), ({'buckets': [[], [], []], 'mask': 7, 'pop': 1}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [0, 1, 2], 'missing': [], 'after_pop': 5}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 8, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [], 'missing': [1, 4], 'after_pop': 8}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 1, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [0], 'missing': [1, 3, 4], 'after_pop': 1})], [({'buckets': [], 'mask': 0, 'pop': 0}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [['a']], 'mask': 1, 'pop': 0}, {'actual_mask': 1, 'minimum': 0, 'maximum': 0, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [[], ['a', 'b'], [], ['c']], 'mask': 10, 'pop': 1}, {'actual_mask': 10, 'minimum': 1, 'maximum': 3, 'ghosts': [], 'missing': [], 'after_pop': 10}), ({'buckets': [['a'], [], ['c']], 'mask': 3, 'pop': 0}, {'actual_mask': 5, 'minimum': 0, 'maximum': 2, 'ghosts': [1], 'missing': [2], 'after_pop': 2}), ({'buckets': [[], [], []], 'mask': 7, 'pop': 1}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [0, 1, 2], 'missing': [], 'after_pop': 5}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 8, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [], 'missing': [1, 4], 'after_pop': 8}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 2, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [], 'missing': [3, 4], 'after_pop': 2})], [({'buckets': [], 'mask': 0, 'pop': 0}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [['a']], 'mask': 1, 'pop': 0}, {'actual_mask': 1, 'minimum': 0, 'maximum': 0, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [[], ['a', 'b'], [], ['c']], 'mask': 10, 'pop': 1}, {'actual_mask': 10, 'minimum': 1, 'maximum': 3, 'ghosts': [], 'missing': [], 'after_pop': 10}), ({'buckets': [['a'], [], ['c']], 'mask': 3, 'pop': 0}, {'actual_mask': 5, 'minimum': 0, 'maximum': 2, 'ghosts': [1], 'missing': [2], 'after_pop': 2}), ({'buckets': [[], [], []], 'mask': 7, 'pop': 1}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [0, 1, 2], 'missing': [], 'after_pop': 5}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 8, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [], 'missing': [1, 4], 'after_pop': 8}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 3, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [0], 'missing': [3, 4], 'after_pop': 3})], [({'buckets': [], 'mask': 0, 'pop': 0}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [['a']], 'mask': 1, 'pop': 0}, {'actual_mask': 1, 'minimum': 0, 'maximum': 0, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [[], ['a', 'b'], [], ['c']], 'mask': 10, 'pop': 1}, {'actual_mask': 10, 'minimum': 1, 'maximum': 3, 'ghosts': [], 'missing': [], 'after_pop': 10}), ({'buckets': [['a'], [], ['c']], 'mask': 3, 'pop': 0}, {'actual_mask': 5, 'minimum': 0, 'maximum': 2, 'ghosts': [1], 'missing': [2], 'after_pop': 2}), ({'buckets': [[], [], []], 'mask': 7, 'pop': 1}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [0, 1, 2], 'missing': [], 'after_pop': 5}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 8, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [], 'missing': [1, 4], 'after_pop': 8}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 4, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [2], 'missing': [1, 3, 4], 'after_pop': 4})], [({'buckets': [], 'mask': 0, 'pop': 0}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [['a']], 'mask': 1, 'pop': 0}, {'actual_mask': 1, 'minimum': 0, 'maximum': 0, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [[], ['a', 'b'], [], ['c']], 'mask': 10, 'pop': 1}, {'actual_mask': 10, 'minimum': 1, 'maximum': 3, 'ghosts': [], 'missing': [], 'after_pop': 10}), ({'buckets': [['a'], [], ['c']], 'mask': 3, 'pop': 0}, {'actual_mask': 5, 'minimum': 0, 'maximum': 2, 'ghosts': [1], 'missing': [2], 'after_pop': 2}), ({'buckets': [[], [], []], 'mask': 7, 'pop': 1}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [0, 1, 2], 'missing': [], 'after_pop': 5}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 8, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [], 'missing': [1, 4], 'after_pop': 8}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 5, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [0, 2], 'missing': [1, 3, 4], 'after_pop': 5})]][N-1]
check('regression certificate 1', solve(cases[0][0]), cases[0][1])
check('regression certificate 2', solve(cases[1][0]), cases[1][1])
check('regression certificate 3', solve(cases[2][0]), cases[2][1])
check('regression certificate 4', solve(cases[3][0]), cases[3][1])
check('regression certificate 5', solve(cases[4][0]), cases[4][1])
check('regression certificate 6', solve(cases[5][0]), cases[5][1])
check('variant-dependent certificate', solve(cases[6][0]), cases[6][1])
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression certificate 1{'actual_mask': 0, 'after_pop': 0, 'ghosts': [], 'maximum': None, 'minimum': None, 'missing': []}{'actual_mask': 0, 'after_pop': 0, 'ghosts': [], 'maximum': None, 'minimum': None, 'missing': []}Passed
regression certificate 2{'actual_mask': 1, 'after_pop': 0, 'ghosts': [], 'maximum': 0, 'minimum': 0, 'missing': []}{'actual_mask': 1, 'after_pop': 0, 'ghosts': [], 'maximum': 0, 'minimum': 0, 'missing': []}Passed
regression certificate 3{'actual_mask': 10, 'after_pop': 8, 'ghosts': [], 'maximum': 3, 'minimum': 1, 'missing': []}{'actual_mask': 10, 'after_pop': 10, 'ghosts': [], 'maximum': 3, 'minimum': 1, 'missing': []}Failed
regression certificate 4{'actual_mask': 5, 'after_pop': 2, 'ghosts': [1], 'maximum': 2, 'minimum': 0, 'missing': [2]}{'actual_mask': 5, 'after_pop': 2, 'ghosts': [1], 'maximum': 2, 'minimum': 0, 'missing': [2]}Passed
regression certificate 5{'actual_mask': 0, 'after_pop': 5, 'ghosts': [0, 1, 2], 'maximum': None, 'minimum': None, 'missing': []}{'actual_mask': 0, 'after_pop': 5, 'ghosts': [0, 1, 2], 'maximum': None, 'minimum': None, 'missing': []}Passed
regression certificate 6{'actual_mask': 26, 'after_pop': 0, 'ghosts': [], 'maximum': 4, 'minimum': 1, 'missing': [1, 4]}{'actual_mask': 26, 'after_pop': 8, 'ghosts': [], 'maximum': 4, 'minimum': 1, 'missing': [1, 4]}Failed
variant-dependent certificate{'actual_mask': 26, 'after_pop': 1, 'ghosts': [0], 'maximum': 4, 'minimum': 1, 'missing': [1, 3, 4]}{'actual_mask': 26, 'after_pop': 1, 'ghosts': [0], 'maximum': 4, 'minimum': 1, 'missing': [1, 3, 4]}Passed

SHA-256 / 00660bc30bc522ff0343ffb29332951ab934e8ce96a025b9a3940a8aaae362ea

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(d):
    b=d['buckets']; mask=d['mask']; p=d['pop']; actual=sum(1<<i for i,x in enumerate(b) if x); remaining=max(0,len(b[p])-1) if b else 0
    return {'actual_mask': actual,
    'minimum': (actual & -actual).bit_length()-1 if actual else None,
    'maximum': actual.bit_length()-1 if actual else None,
    'ghosts': [i for i,x in enumerate(b) if mask&(1<<i) and not x],
    'missing': [i for i,x in enumerate(b) if x and not mask&(1<<i)],
    'after_pop': mask ^ (1<<p) if b else mask}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[({'buckets': [], 'mask': 0, 'pop': 0}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [['a']], 'mask': 1, 'pop': 0}, {'actual_mask': 1, 'minimum': 0, 'maximum': 0, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [[], ['a', 'b'], [], ['c']], 'mask': 10, 'pop': 1}, {'actual_mask': 10, 'minimum': 1, 'maximum': 3, 'ghosts': [], 'missing': [], 'after_pop': 10}), ({'buckets': [['a'], [], ['c']], 'mask': 3, 'pop': 0}, {'actual_mask': 5, 'minimum': 0, 'maximum': 2, 'ghosts': [1], 'missing': [2], 'after_pop': 2}), ({'buckets': [[], [], []], 'mask': 7, 'pop': 1}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [0, 1, 2], 'missing': [], 'after_pop': 5}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 8, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [], 'missing': [1, 4], 'after_pop': 8}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 1, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [0], 'missing': [1, 3, 4], 'after_pop': 1})], [({'buckets': [], 'mask': 0, 'pop': 0}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [['a']], 'mask': 1, 'pop': 0}, {'actual_mask': 1, 'minimum': 0, 'maximum': 0, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [[], ['a', 'b'], [], ['c']], 'mask': 10, 'pop': 1}, {'actual_mask': 10, 'minimum': 1, 'maximum': 3, 'ghosts': [], 'missing': [], 'after_pop': 10}), ({'buckets': [['a'], [], ['c']], 'mask': 3, 'pop': 0}, {'actual_mask': 5, 'minimum': 0, 'maximum': 2, 'ghosts': [1], 'missing': [2], 'after_pop': 2}), ({'buckets': [[], [], []], 'mask': 7, 'pop': 1}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [0, 1, 2], 'missing': [], 'after_pop': 5}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 8, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [], 'missing': [1, 4], 'after_pop': 8}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 2, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [], 'missing': [3, 4], 'after_pop': 2})], [({'buckets': [], 'mask': 0, 'pop': 0}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [['a']], 'mask': 1, 'pop': 0}, {'actual_mask': 1, 'minimum': 0, 'maximum': 0, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [[], ['a', 'b'], [], ['c']], 'mask': 10, 'pop': 1}, {'actual_mask': 10, 'minimum': 1, 'maximum': 3, 'ghosts': [], 'missing': [], 'after_pop': 10}), ({'buckets': [['a'], [], ['c']], 'mask': 3, 'pop': 0}, {'actual_mask': 5, 'minimum': 0, 'maximum': 2, 'ghosts': [1], 'missing': [2], 'after_pop': 2}), ({'buckets': [[], [], []], 'mask': 7, 'pop': 1}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [0, 1, 2], 'missing': [], 'after_pop': 5}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 8, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [], 'missing': [1, 4], 'after_pop': 8}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 3, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [0], 'missing': [3, 4], 'after_pop': 3})], [({'buckets': [], 'mask': 0, 'pop': 0}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [['a']], 'mask': 1, 'pop': 0}, {'actual_mask': 1, 'minimum': 0, 'maximum': 0, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [[], ['a', 'b'], [], ['c']], 'mask': 10, 'pop': 1}, {'actual_mask': 10, 'minimum': 1, 'maximum': 3, 'ghosts': [], 'missing': [], 'after_pop': 10}), ({'buckets': [['a'], [], ['c']], 'mask': 3, 'pop': 0}, {'actual_mask': 5, 'minimum': 0, 'maximum': 2, 'ghosts': [1], 'missing': [2], 'after_pop': 2}), ({'buckets': [[], [], []], 'mask': 7, 'pop': 1}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [0, 1, 2], 'missing': [], 'after_pop': 5}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 8, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [], 'missing': [1, 4], 'after_pop': 8}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 4, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [2], 'missing': [1, 3, 4], 'after_pop': 4})], [({'buckets': [], 'mask': 0, 'pop': 0}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [['a']], 'mask': 1, 'pop': 0}, {'actual_mask': 1, 'minimum': 0, 'maximum': 0, 'ghosts': [], 'missing': [], 'after_pop': 0}), ({'buckets': [[], ['a', 'b'], [], ['c']], 'mask': 10, 'pop': 1}, {'actual_mask': 10, 'minimum': 1, 'maximum': 3, 'ghosts': [], 'missing': [], 'after_pop': 10}), ({'buckets': [['a'], [], ['c']], 'mask': 3, 'pop': 0}, {'actual_mask': 5, 'minimum': 0, 'maximum': 2, 'ghosts': [1], 'missing': [2], 'after_pop': 2}), ({'buckets': [[], [], []], 'mask': 7, 'pop': 1}, {'actual_mask': 0, 'minimum': None, 'maximum': None, 'ghosts': [0, 1, 2], 'missing': [], 'after_pop': 5}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 8, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [], 'missing': [1, 4], 'after_pop': 8}), ({'buckets': [[], ['x'], [], ['y', 'z'], ['q']], 'mask': 5, 'pop': 3}, {'actual_mask': 26, 'minimum': 1, 'maximum': 4, 'ghosts': [0, 2], 'missing': [1, 3, 4], 'after_pop': 5})]][N-1]
check('regression certificate 1', solve(cases[0][0]), cases[0][1])
check('regression certificate 2', solve(cases[1][0]), cases[1][1])
check('regression certificate 3', solve(cases[2][0]), cases[2][1])
check('regression certificate 4', solve(cases[3][0]), cases[3][1])
check('regression certificate 5', solve(cases[4][0]), cases[4][1])
check('regression certificate 6', solve(cases[5][0]), cases[5][1])
check('variant-dependent certificate', solve(cases[6][0]), cases[6][1])
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression certificate 1{'actual_mask': 0, 'after_pop': 0, 'ghosts': [], 'maximum': None, 'minimum': None, 'missing': []}{'actual_mask': 0, 'after_pop': 0, 'ghosts': [], 'maximum': None, 'minimum': None, 'missing': []}Passed
regression certificate 2{'actual_mask': 1, 'after_pop': 0, 'ghosts': [], 'maximum': 0, 'minimum': 0, 'missing': []}{'actual_mask': 1, 'after_pop': 0, 'ghosts': [], 'maximum': 0, 'minimum': 0, 'missing': []}Passed
regression certificate 3{'actual_mask': 10, 'after_pop': 8, 'ghosts': [], 'maximum': 3, 'minimum': 1, 'missing': []}{'actual_mask': 10, 'after_pop': 10, 'ghosts': [], 'maximum': 3, 'minimum': 1, 'missing': []}Failed
regression certificate 4{'actual_mask': 5, 'after_pop': 2, 'ghosts': [1], 'maximum': 2, 'minimum': 0, 'missing': [2]}{'actual_mask': 5, 'after_pop': 2, 'ghosts': [1], 'maximum': 2, 'minimum': 0, 'missing': [2]}Passed
regression certificate 5{'actual_mask': 0, 'after_pop': 5, 'ghosts': [0, 1, 2], 'maximum': None, 'minimum': None, 'missing': []}{'actual_mask': 0, 'after_pop': 5, 'ghosts': [0, 1, 2], 'maximum': None, 'minimum': None, 'missing': []}Passed
regression certificate 6{'actual_mask': 26, 'after_pop': 0, 'ghosts': [], 'maximum': 4, 'minimum': 1, 'missing': [1, 4]}{'actual_mask': 26, 'after_pop': 8, 'ghosts': [], 'maximum': 4, 'minimum': 1, 'missing': [1, 4]}Failed
variant-dependent certificate{'actual_mask': 26, 'after_pop': 9, 'ghosts': [0], 'maximum': 4, 'minimum': 1, 'missing': [1, 3, 4]}{'actual_mask': 26, 'after_pop': 1, 'ghosts': [0], 'maximum': 4, 'minimum': 1, 'missing': [1, 3, 4]}Failed

SHA-256 / b54dbf1685497fac640d18f3996b46b0e489543775cc6372e8e79da3e70c8be9

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 7 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

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Verification & scope

A stipulated offline diagnostic model; it does not implement a production allocator, concurrency protocol, or complete heap library. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:43:35.130010+00:00.

Case digest / deb242117ddce39b847ca003b3aeae4275f7a9a7ad53092ae7a26defe8a555b1