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FA-17976 / Time representation / Open access

Possible timestamp ordering is confused with definite ordering · case 01

The decoded time state disagrees with the explicit regression oracle for possible_before.

Verified by executionVariant 1 · 11 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Possible timestamp ordering is confused with definite ordering.

VERIFIED REPAIR

Preserve the declared coordinate and state contract at possible_before: possible_before = compatible and r['a'] < b_end.

Unsuccessful approach: The partial correction still substitutes compatible and r['a'] <= b_end at the same fault site.

Case contract

A timestamp rounded down to resolution q represents half-open [stamp,stamp+q). Preserve domain tag; q positive. Comparing two buckets yields exact intersection and possible/definite-before relations, equality of represented sets and union envelope. Query membership is half-open. This model handles precision buckets, not point timestamps.

Why this case matters

Clock transfer and timestamp consumers require preserved coordinate, phase, validity and elapsed-time semantics.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
from fractions import Fraction
N = 1
observations = []
def solve(r):
    a_end = r['a'] + r['qa']
    b_end = r['b'] + r['qb']
    compatible = r['domain_a'] == r['domain_b']
    low = max(r['a'],r['b'])
    high = min(a_end,b_end)
    overlap = compatible and low < high
    definite_before = compatible and a_end <= r['b']
    possible_before = compatible and a_end < r['b']
    equal = compatible and r['a'] == r['b'] and r['qa'] == r['qb']
    contains = r['a'] <= r['query'] < a_end
    return [None if not overlap else [low,high],definite_before,possible_before,equal,contains, None if not compatible else [min(r['a'],r['b']),max(a_end,b_end)]]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({'a': 10, 'qa': 10, 'b': 15, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}), [[15, 20], False, True, False, True, [10, 35]])
check('fixture 2', solve({'a': 10, 'qa': 10, 'b': 20, 'qb': 2, 'query': 20, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, True, True, False, False, [10, 22]])
check('fixture 3', solve({'a': 10, 'qa': 10, 'b': 10, 'qb': 2, 'query': 15, 'domain_a': 'utc', 'domain_b': 'utc'}), [[10, 12], False, True, False, True, [10, 20]])
check('fixture 4', solve({'a': 20, 'qa': 2, 'b': 10, 'qb': 10, 'query': 21, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, False, False, False, True, [10, 22]])
check('fixture 5', solve({'a': 0, 'qa': 1, 'b': 0, 'qb': 1, 'query': 0, 'domain_a': 'mono', 'domain_b': 'mono'}), [[0, 1], False, True, True, True, [0, 1]])
check('fixture 6', solve({'a': 0, 'qa': 10, 'b': 2, 'qb': 3, 'query': 2, 'domain_a': 'a', 'domain_b': 'b'}), [None, False, False, False, True, None])
check('fixture 7', solve({'a': -10, 'qa': 5, 'b': -8, 'qb': 1, 'query': -5, 'domain_a': 'utc', 'domain_b': 'utc'}), [[-8, -7], False, True, False, False, [-10, -5]])
check('fixture 8', solve({'a': 0, 'qa': 3, 'b': 2, 'qb': 1, 'query': 1, 'domain_a': 'utc', 'domain_b': 'utc'}), [[2, 3], False, True, False, True, [0, 3]])
check('fixture 9', solve({'a': 10, 'qa': 1, 'b': 20, 'qb': 1, 'query': 11, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, True, True, False, False, [10, 21]])
check('fixture 10', solve({'a': 0, 'qa': 1, 'b': -1, 'qb': 1, 'query': 0, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, False, False, False, True, [-1, 1]])
variant = [({'a': 10, 'qa': 10, 'b': 16, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[16, 20], False, True, False, True, [10, 36]]), ({'a': 10, 'qa': 10, 'b': 17, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[17, 20], False, True, False, True, [10, 37]]), ({'a': 10, 'qa': 10, 'b': 18, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[18, 20], False, True, False, True, [10, 38]]), ({'a': 10, 'qa': 10, 'b': 19, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[19, 20], False, True, False, True, [10, 39]]), ({'a': 10, 'qa': 10, 'b': 20, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [None, True, True, False, True, [10, 40]])]
check("variant capture", solve(variant[N-1][0]), variant[N-1][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
fixture 1[[15, 20], False, False, False, True, [10, 35]][[15, 20], False, True, False, True, [10, 35]]Failed
fixture 2[None, True, False, False, False, [10, 22]][None, True, True, False, False, [10, 22]]Failed
fixture 3[[10, 12], False, False, False, True, [10, 20]][[10, 12], False, True, False, True, [10, 20]]Failed
fixture 4[None, False, False, False, True, [10, 22]][None, False, False, False, True, [10, 22]]Passed
fixture 5[[0, 1], False, False, True, True, [0, 1]][[0, 1], False, True, True, True, [0, 1]]Failed
fixture 6[None, False, False, False, True, None][None, False, False, False, True, None]Passed
fixture 7[[-8, -7], False, False, False, False, [-10, -5]][[-8, -7], False, True, False, False, [-10, -5]]Failed
fixture 8[[2, 3], False, False, False, True, [0, 3]][[2, 3], False, True, False, True, [0, 3]]Failed
fixture 9[None, True, True, False, False, [10, 21]][None, True, True, False, False, [10, 21]]Passed
fixture 10[None, False, False, False, True, [-1, 1]][None, False, False, False, True, [-1, 1]]Passed
variant capture[[16, 20], False, False, False, True, [10, 36]][[16, 20], False, True, False, True, [10, 36]]Failed

SHA-256 / 9c1e4715ef2c8b124d31f532aaed23d912023687d37bc6b84db354243f5eee10

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
from fractions import Fraction
N = 1
observations = []
def solve(r):
    a_end = r['a'] + r['qa']
    b_end = r['b'] + r['qb']
    compatible = r['domain_a'] == r['domain_b']
    low = max(r['a'],r['b'])
    high = min(a_end,b_end)
    overlap = compatible and low < high
    definite_before = compatible and a_end <= r['b']
    possible_before = compatible and r['a'] <= b_end
    equal = compatible and r['a'] == r['b'] and r['qa'] == r['qb']
    contains = r['a'] <= r['query'] < a_end
    return [None if not overlap else [low,high],definite_before,possible_before,equal,contains, None if not compatible else [min(r['a'],r['b']),max(a_end,b_end)]]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({'a': 10, 'qa': 10, 'b': 15, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}), [[15, 20], False, True, False, True, [10, 35]])
check('fixture 2', solve({'a': 10, 'qa': 10, 'b': 20, 'qb': 2, 'query': 20, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, True, True, False, False, [10, 22]])
check('fixture 3', solve({'a': 10, 'qa': 10, 'b': 10, 'qb': 2, 'query': 15, 'domain_a': 'utc', 'domain_b': 'utc'}), [[10, 12], False, True, False, True, [10, 20]])
check('fixture 4', solve({'a': 20, 'qa': 2, 'b': 10, 'qb': 10, 'query': 21, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, False, False, False, True, [10, 22]])
check('fixture 5', solve({'a': 0, 'qa': 1, 'b': 0, 'qb': 1, 'query': 0, 'domain_a': 'mono', 'domain_b': 'mono'}), [[0, 1], False, True, True, True, [0, 1]])
check('fixture 6', solve({'a': 0, 'qa': 10, 'b': 2, 'qb': 3, 'query': 2, 'domain_a': 'a', 'domain_b': 'b'}), [None, False, False, False, True, None])
check('fixture 7', solve({'a': -10, 'qa': 5, 'b': -8, 'qb': 1, 'query': -5, 'domain_a': 'utc', 'domain_b': 'utc'}), [[-8, -7], False, True, False, False, [-10, -5]])
check('fixture 8', solve({'a': 0, 'qa': 3, 'b': 2, 'qb': 1, 'query': 1, 'domain_a': 'utc', 'domain_b': 'utc'}), [[2, 3], False, True, False, True, [0, 3]])
check('fixture 9', solve({'a': 10, 'qa': 1, 'b': 20, 'qb': 1, 'query': 11, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, True, True, False, False, [10, 21]])
check('fixture 10', solve({'a': 0, 'qa': 1, 'b': -1, 'qb': 1, 'query': 0, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, False, False, False, True, [-1, 1]])
variant = [({'a': 10, 'qa': 10, 'b': 16, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[16, 20], False, True, False, True, [10, 36]]), ({'a': 10, 'qa': 10, 'b': 17, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[17, 20], False, True, False, True, [10, 37]]), ({'a': 10, 'qa': 10, 'b': 18, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[18, 20], False, True, False, True, [10, 38]]), ({'a': 10, 'qa': 10, 'b': 19, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[19, 20], False, True, False, True, [10, 39]]), ({'a': 10, 'qa': 10, 'b': 20, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [None, True, True, False, True, [10, 40]])]
check("variant capture", solve(variant[N-1][0]), variant[N-1][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
fixture 1[[15, 20], False, True, False, True, [10, 35]][[15, 20], False, True, False, True, [10, 35]]Passed
fixture 2[None, True, True, False, False, [10, 22]][None, True, True, False, False, [10, 22]]Passed
fixture 3[[10, 12], False, True, False, True, [10, 20]][[10, 12], False, True, False, True, [10, 20]]Passed
fixture 4[None, False, True, False, True, [10, 22]][None, False, False, False, True, [10, 22]]Failed
fixture 5[[0, 1], False, True, True, True, [0, 1]][[0, 1], False, True, True, True, [0, 1]]Passed
fixture 6[None, False, False, False, True, None][None, False, False, False, True, None]Passed
fixture 7[[-8, -7], False, True, False, False, [-10, -5]][[-8, -7], False, True, False, False, [-10, -5]]Passed
fixture 8[[2, 3], False, True, False, True, [0, 3]][[2, 3], False, True, False, True, [0, 3]]Passed
fixture 9[None, True, True, False, False, [10, 21]][None, True, True, False, False, [10, 21]]Passed
fixture 10[None, False, True, False, True, [-1, 1]][None, False, False, False, True, [-1, 1]]Failed
variant capture[[16, 20], False, True, False, True, [10, 36]][[16, 20], False, True, False, True, [10, 36]]Passed

SHA-256 / 1386aa8e40b96cc04f5f353df33b9a89c29820288eff1e3f047352ca88f7d3ee

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json
from fractions import Fraction
N = 1
observations = []
def solve(r):
    a_end = r['a'] + r['qa']
    b_end = r['b'] + r['qb']
    compatible = r['domain_a'] == r['domain_b']
    low = max(r['a'],r['b'])
    high = min(a_end,b_end)
    overlap = compatible and low < high
    definite_before = compatible and a_end <= r['b']
    possible_before = compatible and r['a'] < b_end
    equal = compatible and r['a'] == r['b'] and r['qa'] == r['qb']
    contains = r['a'] <= r['query'] < a_end
    return [None if not overlap else [low,high],definite_before,possible_before,equal,contains, None if not compatible else [min(r['a'],r['b']),max(a_end,b_end)]]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({'a': 10, 'qa': 10, 'b': 15, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}), [[15, 20], False, True, False, True, [10, 35]])
check('fixture 2', solve({'a': 10, 'qa': 10, 'b': 20, 'qb': 2, 'query': 20, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, True, True, False, False, [10, 22]])
check('fixture 3', solve({'a': 10, 'qa': 10, 'b': 10, 'qb': 2, 'query': 15, 'domain_a': 'utc', 'domain_b': 'utc'}), [[10, 12], False, True, False, True, [10, 20]])
check('fixture 4', solve({'a': 20, 'qa': 2, 'b': 10, 'qb': 10, 'query': 21, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, False, False, False, True, [10, 22]])
check('fixture 5', solve({'a': 0, 'qa': 1, 'b': 0, 'qb': 1, 'query': 0, 'domain_a': 'mono', 'domain_b': 'mono'}), [[0, 1], False, True, True, True, [0, 1]])
check('fixture 6', solve({'a': 0, 'qa': 10, 'b': 2, 'qb': 3, 'query': 2, 'domain_a': 'a', 'domain_b': 'b'}), [None, False, False, False, True, None])
check('fixture 7', solve({'a': -10, 'qa': 5, 'b': -8, 'qb': 1, 'query': -5, 'domain_a': 'utc', 'domain_b': 'utc'}), [[-8, -7], False, True, False, False, [-10, -5]])
check('fixture 8', solve({'a': 0, 'qa': 3, 'b': 2, 'qb': 1, 'query': 1, 'domain_a': 'utc', 'domain_b': 'utc'}), [[2, 3], False, True, False, True, [0, 3]])
check('fixture 9', solve({'a': 10, 'qa': 1, 'b': 20, 'qb': 1, 'query': 11, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, True, True, False, False, [10, 21]])
check('fixture 10', solve({'a': 0, 'qa': 1, 'b': -1, 'qb': 1, 'query': 0, 'domain_a': 'utc', 'domain_b': 'utc'}), [None, False, False, False, True, [-1, 1]])
variant = [({'a': 10, 'qa': 10, 'b': 16, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[16, 20], False, True, False, True, [10, 36]]), ({'a': 10, 'qa': 10, 'b': 17, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[17, 20], False, True, False, True, [10, 37]]), ({'a': 10, 'qa': 10, 'b': 18, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[18, 20], False, True, False, True, [10, 38]]), ({'a': 10, 'qa': 10, 'b': 19, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [[19, 20], False, True, False, True, [10, 39]]), ({'a': 10, 'qa': 10, 'b': 20, 'qb': 20, 'query': 10, 'domain_a': 'utc', 'domain_b': 'utc'}, [None, True, True, False, True, [10, 40]])]
check("variant capture", solve(variant[N-1][0]), variant[N-1][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
fixture 1[[15, 20], False, True, False, True, [10, 35]][[15, 20], False, True, False, True, [10, 35]]Passed
fixture 2[None, True, True, False, False, [10, 22]][None, True, True, False, False, [10, 22]]Passed
fixture 3[[10, 12], False, True, False, True, [10, 20]][[10, 12], False, True, False, True, [10, 20]]Passed
fixture 4[None, False, False, False, True, [10, 22]][None, False, False, False, True, [10, 22]]Passed
fixture 5[[0, 1], False, True, True, True, [0, 1]][[0, 1], False, True, True, True, [0, 1]]Passed
fixture 6[None, False, False, False, True, None][None, False, False, False, True, None]Passed
fixture 7[[-8, -7], False, True, False, False, [-10, -5]][[-8, -7], False, True, False, False, [-10, -5]]Passed
fixture 8[[2, 3], False, True, False, True, [0, 3]][[2, 3], False, True, False, True, [0, 3]]Passed
fixture 9[None, True, True, False, False, [10, 21]][None, True, True, False, False, [10, 21]]Passed
fixture 10[None, False, False, False, True, [-1, 1]][None, False, False, False, True, [-1, 1]]Passed
variant capture[[16, 20], False, True, False, True, [10, 36]][[16, 20], False, True, False, True, [10, 36]]Passed

SHA-256 / 89c84c19b65aab734ab1e19512bb8eea405fa3173b8db1203db8750a5b0ddb7a

Verification & scope

Deterministic integer reference model with stipulated units and policies; not a complete clock, wire standard or platform implementation. 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 2026-09-29T14:39:52.828961+00:00.

Case digest / 5670b18285e08d96c23f3d467fa2c9a8aaef2b74d1cbee707fec742df1bedec6