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FA-17691 / Time representation / Open access

Civil gap starts on the wrong offset branch · case 01

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

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

ROOT CAUSE

Civil gap starts on the wrong offset branch.

THE FAILURE

Civil gap starts on the wrong offset branch.

Unsuccessful approach: The partial correction still substitutes r['transition'] + r['new'] at the same fault site.

Case contract

A stipulated forward offset transition at UTC T creates local gap [T+old,T+new). Reject returns None, forward adds gap width and backward subtracts it, preserving position in the gap. Return resolved local coordinate, UTC coordinate, shift direction and successful-change flag. Outside-gap labels are unchanged.

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):
    start = r['transition'] - r['old']
    end = r['transition'] + r['new']
    width = r['new'] - r['old']
    in_gap = start <= r['local'] < end
    shift = (width if r['policy'] == 'forward' else -width) if in_gap and r['policy'] != 'reject' else 0
    resolved = None if in_gap and r['policy'] == 'reject' else r['local'] + shift
    offset = None if resolved is None else (r['old'] if resolved < start else r['new'])
    utc = None if resolved is None else resolved - offset
    direction = (shift > 0) - (shift < 0)
    changed = resolved is not None and resolved != r['local']
    return [resolved,utc,direction,changed]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({'local': 109, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}), [109, 99, 0, False])
check('fixture 2', solve({'local': 110, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}), [130, 100, 1, True])
check('fixture 3', solve({'local': 110, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'backward'}), [90, 80, -1, True])
check('fixture 4', solve({'local': 110, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'reject'}), [None, None, 0, False])
check('fixture 5', solve({'local': 129, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'backward'}), [109, 99, -1, True])
check('fixture 6', solve({'local': 130, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'reject'}), [130, 100, 0, False])
check('fixture 7', solve({'local': 120, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}), [140, 110, 1, True])
check('fixture 8', solve({'local': 120, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'reject'}), [None, None, 0, False])
check('fixture 9', solve({'local': -20, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'backward'}), [-20, -30, 0, False])
check('fixture 10', solve({'local': 140, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}), [140, 110, 0, False])
variant = [({'local': 110, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}, [130, 100, 1, True]), ({'local': 111, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}, [131, 101, 1, True]), ({'local': 112, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}, [132, 102, 1, True]), ({'local': 113, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}, [133, 103, 1, True]), ({'local': 114, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}, [134, 104, 1, True])]
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[129, 99, 1, True][109, 99, 0, False]Failed
fixture 2[130, 100, 1, True][130, 100, 1, True]Passed
fixture 3[90, 60, -1, True][90, 80, -1, True]Failed
fixture 4[None, None, 0, False][None, None, 0, False]Passed
fixture 5[109, 79, -1, True][109, 99, -1, True]Failed
fixture 6[130, 100, 0, False][130, 100, 0, False]Passed
fixture 7[140, 110, 1, True][140, 110, 1, True]Passed
fixture 8[None, None, 0, False][None, None, 0, False]Passed
fixture 9[-20, -30, 0, False][-20, -30, 0, False]Passed
fixture 10[140, 110, 0, False][140, 110, 0, False]Passed
variant capture[130, 100, 1, True][130, 100, 1, True]Passed

SHA-256 / f17ccf91f9417c2c370b8da0ee8a391f4786b4877b9c8bc1cd4e5d209bd7df74

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):
    start = r['transition'] + r['new']
    end = r['transition'] + r['new']
    width = r['new'] - r['old']
    in_gap = start <= r['local'] < end
    shift = (width if r['policy'] == 'forward' else -width) if in_gap and r['policy'] != 'reject' else 0
    resolved = None if in_gap and r['policy'] == 'reject' else r['local'] + shift
    offset = None if resolved is None else (r['old'] if resolved < start else r['new'])
    utc = None if resolved is None else resolved - offset
    direction = (shift > 0) - (shift < 0)
    changed = resolved is not None and resolved != r['local']
    return [resolved,utc,direction,changed]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({'local': 109, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}), [109, 99, 0, False])
check('fixture 2', solve({'local': 110, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}), [130, 100, 1, True])
check('fixture 3', solve({'local': 110, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'backward'}), [90, 80, -1, True])
check('fixture 4', solve({'local': 110, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'reject'}), [None, None, 0, False])
check('fixture 5', solve({'local': 129, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'backward'}), [109, 99, -1, True])
check('fixture 6', solve({'local': 130, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'reject'}), [130, 100, 0, False])
check('fixture 7', solve({'local': 120, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}), [140, 110, 1, True])
check('fixture 8', solve({'local': 120, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'reject'}), [None, None, 0, False])
check('fixture 9', solve({'local': -20, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'backward'}), [-20, -30, 0, False])
check('fixture 10', solve({'local': 140, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}), [140, 110, 0, False])
variant = [({'local': 110, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}, [130, 100, 1, True]), ({'local': 111, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}, [131, 101, 1, True]), ({'local': 112, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}, [132, 102, 1, True]), ({'local': 113, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}, [133, 103, 1, True]), ({'local': 114, 'old': 10, 'new': 30, 'transition': 100, 'policy': 'forward'}, [134, 104, 1, True])]
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[109, 99, 0, False][109, 99, 0, False]Passed
fixture 2[110, 100, 0, False][130, 100, 1, True]Failed
fixture 3[110, 100, 0, False][90, 80, -1, True]Failed
fixture 4[110, 100, 0, False][None, None, 0, False]Failed
fixture 5[129, 119, 0, False][109, 99, -1, True]Failed
fixture 6[130, 100, 0, False][130, 100, 0, False]Passed
fixture 7[120, 110, 0, False][140, 110, 1, True]Failed
fixture 8[120, 110, 0, False][None, None, 0, False]Failed
fixture 9[-20, -30, 0, False][-20, -30, 0, False]Passed
fixture 10[140, 110, 0, False][140, 110, 0, False]Passed
variant capture[110, 100, 0, False][130, 100, 1, True]Failed

SHA-256 / ce73322c318f66fd3a8cdc8cbd1e297c42c4bc38f1d411c181127eca843a20e0

HELD IN THE MEMBER ARCHIVE

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

This mechanism has 11 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

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 2026-09-29T14:39:49.950528+00:00.

Case digest / f64002e83c16fcbb85120a08de8a141eec505d94ad1d77bc87fc441e58d8a230