FAILURE MAP
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FA-17346 / Time representation / Open access

Monotonic displacement reverses checkpoint subtraction · case 01

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

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

ROOT CAUSE

Monotonic displacement reverses checkpoint subtraction.

VERIFIED REPAIR

Preserve the declared coordinate and state contract at mono_delta: mono_delta = r['mono_now'] - r['mono_saved'].

Unsuccessful approach: The partial correction still substitutes abs(r['mono_now']) - abs(r['mono_saved']) at the same fault site.

Case contract

A checkpoint stores wall and monotonic coordinates, boot identity, budget and pause state. Same-boot restore uses monotonic elapsed; reboot restore uses nonnegative wall elapsed. Paused timers consume no elapsed ticks. Return remaining budget, expiration flag, overdue ticks, current-domain deadline (None while paused), and reconstructed running base. All units are identical integer ticks.

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):
    wall_delta = r['wall_now'] - r['wall_saved']
    mono_delta = r['mono_saved'] - r['mono_now']
    reboot = r['boot_now'] != r['boot_saved']
    elapsed = max(0, wall_delta if reboot else mono_delta)
    consumed = 0 if r['paused'] else elapsed
    remaining = max(0, r['budget'] - consumed)
    expired = not r['paused'] and consumed >= r['budget']
    overdue = max(0, consumed - r['budget'])
    deadline = None if r['paused'] else r['mono_now'] + remaining
    base = r['mono_now'] - consumed
    return [remaining,expired,overdue,deadline,base]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 30}), [0, True, 0, 50, 20])
check('fixture 2', solve({'wall_now': 90, 'wall_saved': 100, 'mono_now': 5, 'mono_saved': 20, 'boot_now': 'b', 'boot_saved': 'a', 'paused': False, 'budget': 10}), [10, False, 0, 15, 5])
check('fixture 3', solve({'wall_now': 150, 'wall_saved': 100, 'mono_now': 5, 'mono_saved': 20, 'boot_now': 'b', 'boot_saved': 'a', 'paused': False, 'budget': 20}), [0, True, 30, 5, -45])
check('fixture 4', solve({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': True, 'budget': 0}), [0, False, 0, None, 50])
check('fixture 5', solve({'wall_now': 140, 'wall_saved': 100, 'mono_now': 60, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 100}), [60, False, 0, 120, 20])
check('fixture 6', solve({'wall_now': 90, 'wall_saved': 100, 'mono_now': -5, 'mono_saved': -20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 20}), [5, False, 0, 0, -20])
check('fixture 7', solve({'wall_now': 101, 'wall_saved': 100, 'mono_now': 0, 'mono_saved': 0, 'boot_now': 'c', 'boot_saved': 'a', 'paused': False, 'budget': 0}), [0, True, 1, 0, -1])
check('fixture 8', solve({'wall_now': 100, 'wall_saved': 100, 'mono_now': 20, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': True, 'budget': 10}), [10, False, 0, None, 20])
check('fixture 9', solve({'wall_now': 105, 'wall_saved': 100, 'mono_now': 24, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 3}), [0, True, 1, 24, 20])
check('fixture 10', solve({'wall_now': 80, 'wall_saved': 100, 'mono_now': -10, 'mono_saved': -20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 0}), [0, True, 10, -10, -20])
variant = [({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 31}, [1, False, 0, 51, 20]), ({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 32}, [2, False, 0, 52, 20]), ({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 33}, [3, False, 0, 53, 20]), ({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 34}, [4, False, 0, 54, 20]), ({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 35}, [5, False, 0, 55, 20])]
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[30, False, 0, 80, 50][0, True, 0, 50, 20]Failed
fixture 2[10, False, 0, 15, 5][10, False, 0, 15, 5]Passed
fixture 3[0, True, 30, 5, -45][0, True, 30, 5, -45]Passed
fixture 4[0, False, 0, None, 50][0, False, 0, None, 50]Passed
fixture 5[100, False, 0, 160, 60][60, False, 0, 120, 20]Failed
fixture 6[20, False, 0, 15, -5][5, False, 0, 0, -20]Failed
fixture 7[0, True, 1, 0, -1][0, True, 1, 0, -1]Passed
fixture 8[10, False, 0, None, 20][10, False, 0, None, 20]Passed
fixture 9[3, False, 0, 27, 24][0, True, 1, 24, 20]Failed
fixture 10[0, True, 0, -10, -10][0, True, 10, -10, -20]Failed
variant capture[31, False, 0, 81, 50][1, False, 0, 51, 20]Failed

SHA-256 / 42e9ac2607caaf3a37dc8d1c39e41ddc635e0b52ddbb2d20ec5f4036a032a348

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):
    wall_delta = r['wall_now'] - r['wall_saved']
    mono_delta = abs(r['mono_now']) - abs(r['mono_saved'])
    reboot = r['boot_now'] != r['boot_saved']
    elapsed = max(0, wall_delta if reboot else mono_delta)
    consumed = 0 if r['paused'] else elapsed
    remaining = max(0, r['budget'] - consumed)
    expired = not r['paused'] and consumed >= r['budget']
    overdue = max(0, consumed - r['budget'])
    deadline = None if r['paused'] else r['mono_now'] + remaining
    base = r['mono_now'] - consumed
    return [remaining,expired,overdue,deadline,base]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 30}), [0, True, 0, 50, 20])
check('fixture 2', solve({'wall_now': 90, 'wall_saved': 100, 'mono_now': 5, 'mono_saved': 20, 'boot_now': 'b', 'boot_saved': 'a', 'paused': False, 'budget': 10}), [10, False, 0, 15, 5])
check('fixture 3', solve({'wall_now': 150, 'wall_saved': 100, 'mono_now': 5, 'mono_saved': 20, 'boot_now': 'b', 'boot_saved': 'a', 'paused': False, 'budget': 20}), [0, True, 30, 5, -45])
check('fixture 4', solve({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': True, 'budget': 0}), [0, False, 0, None, 50])
check('fixture 5', solve({'wall_now': 140, 'wall_saved': 100, 'mono_now': 60, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 100}), [60, False, 0, 120, 20])
check('fixture 6', solve({'wall_now': 90, 'wall_saved': 100, 'mono_now': -5, 'mono_saved': -20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 20}), [5, False, 0, 0, -20])
check('fixture 7', solve({'wall_now': 101, 'wall_saved': 100, 'mono_now': 0, 'mono_saved': 0, 'boot_now': 'c', 'boot_saved': 'a', 'paused': False, 'budget': 0}), [0, True, 1, 0, -1])
check('fixture 8', solve({'wall_now': 100, 'wall_saved': 100, 'mono_now': 20, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': True, 'budget': 10}), [10, False, 0, None, 20])
check('fixture 9', solve({'wall_now': 105, 'wall_saved': 100, 'mono_now': 24, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 3}), [0, True, 1, 24, 20])
check('fixture 10', solve({'wall_now': 80, 'wall_saved': 100, 'mono_now': -10, 'mono_saved': -20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 0}), [0, True, 10, -10, -20])
variant = [({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 31}, [1, False, 0, 51, 20]), ({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 32}, [2, False, 0, 52, 20]), ({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 33}, [3, False, 0, 53, 20]), ({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 34}, [4, False, 0, 54, 20]), ({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 35}, [5, False, 0, 55, 20])]
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[0, True, 0, 50, 20][0, True, 0, 50, 20]Passed
fixture 2[10, False, 0, 15, 5][10, False, 0, 15, 5]Passed
fixture 3[0, True, 30, 5, -45][0, True, 30, 5, -45]Passed
fixture 4[0, False, 0, None, 50][0, False, 0, None, 50]Passed
fixture 5[60, False, 0, 120, 20][60, False, 0, 120, 20]Passed
fixture 6[20, False, 0, 15, -5][5, False, 0, 0, -20]Failed
fixture 7[0, True, 1, 0, -1][0, True, 1, 0, -1]Passed
fixture 8[10, False, 0, None, 20][10, False, 0, None, 20]Passed
fixture 9[0, True, 1, 24, 20][0, True, 1, 24, 20]Passed
fixture 10[0, True, 0, -10, -10][0, True, 10, -10, -20]Failed
variant capture[1, False, 0, 51, 20][1, False, 0, 51, 20]Passed

SHA-256 / 8de4f7368a7d6e1cb8c40c8e726c199c592e0cccd16883288bbc18923ffd611b

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):
    wall_delta = r['wall_now'] - r['wall_saved']
    mono_delta = r['mono_now'] - r['mono_saved']
    reboot = r['boot_now'] != r['boot_saved']
    elapsed = max(0, wall_delta if reboot else mono_delta)
    consumed = 0 if r['paused'] else elapsed
    remaining = max(0, r['budget'] - consumed)
    expired = not r['paused'] and consumed >= r['budget']
    overdue = max(0, consumed - r['budget'])
    deadline = None if r['paused'] else r['mono_now'] + remaining
    base = r['mono_now'] - consumed
    return [remaining,expired,overdue,deadline,base]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 30}), [0, True, 0, 50, 20])
check('fixture 2', solve({'wall_now': 90, 'wall_saved': 100, 'mono_now': 5, 'mono_saved': 20, 'boot_now': 'b', 'boot_saved': 'a', 'paused': False, 'budget': 10}), [10, False, 0, 15, 5])
check('fixture 3', solve({'wall_now': 150, 'wall_saved': 100, 'mono_now': 5, 'mono_saved': 20, 'boot_now': 'b', 'boot_saved': 'a', 'paused': False, 'budget': 20}), [0, True, 30, 5, -45])
check('fixture 4', solve({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': True, 'budget': 0}), [0, False, 0, None, 50])
check('fixture 5', solve({'wall_now': 140, 'wall_saved': 100, 'mono_now': 60, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 100}), [60, False, 0, 120, 20])
check('fixture 6', solve({'wall_now': 90, 'wall_saved': 100, 'mono_now': -5, 'mono_saved': -20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 20}), [5, False, 0, 0, -20])
check('fixture 7', solve({'wall_now': 101, 'wall_saved': 100, 'mono_now': 0, 'mono_saved': 0, 'boot_now': 'c', 'boot_saved': 'a', 'paused': False, 'budget': 0}), [0, True, 1, 0, -1])
check('fixture 8', solve({'wall_now': 100, 'wall_saved': 100, 'mono_now': 20, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': True, 'budget': 10}), [10, False, 0, None, 20])
check('fixture 9', solve({'wall_now': 105, 'wall_saved': 100, 'mono_now': 24, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 3}), [0, True, 1, 24, 20])
check('fixture 10', solve({'wall_now': 80, 'wall_saved': 100, 'mono_now': -10, 'mono_saved': -20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 0}), [0, True, 10, -10, -20])
variant = [({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 31}, [1, False, 0, 51, 20]), ({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 32}, [2, False, 0, 52, 20]), ({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 33}, [3, False, 0, 53, 20]), ({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 34}, [4, False, 0, 54, 20]), ({'wall_now': 130, 'wall_saved': 100, 'mono_now': 50, 'mono_saved': 20, 'boot_now': 'a', 'boot_saved': 'a', 'paused': False, 'budget': 35}, [5, False, 0, 55, 20])]
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[0, True, 0, 50, 20][0, True, 0, 50, 20]Passed
fixture 2[10, False, 0, 15, 5][10, False, 0, 15, 5]Passed
fixture 3[0, True, 30, 5, -45][0, True, 30, 5, -45]Passed
fixture 4[0, False, 0, None, 50][0, False, 0, None, 50]Passed
fixture 5[60, False, 0, 120, 20][60, False, 0, 120, 20]Passed
fixture 6[5, False, 0, 0, -20][5, False, 0, 0, -20]Passed
fixture 7[0, True, 1, 0, -1][0, True, 1, 0, -1]Passed
fixture 8[10, False, 0, None, 20][10, False, 0, None, 20]Passed
fixture 9[0, True, 1, 24, 20][0, True, 1, 24, 20]Passed
fixture 10[0, True, 10, -10, -20][0, True, 10, -10, -20]Passed
variant capture[1, False, 0, 51, 20][1, False, 0, 51, 20]Passed

SHA-256 / 2a90944ccd9081ed15d9d0da623aae8d6d074a1416545eda60ce3e2b80871917

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 2026-09-29T14:39:45.422743+00:00.

Case digest / 4661a42dea1d152b00a89c14317e089099b8155d78f25b33bdfc13323f34c599