FA-50386 / Raster clipping / Open access
Saved clip stack: enable resets · case 01
Enabling silently replaces the retained clip with the target extent.
ROOT CAUSE
Enabling silently replaces the retained clip with the target extent.
THE FAILURE
Enabling silently replaces the retained clip with the target extent.
Unsuccessful approach: Preserving nonempty clips while treating empty clips as uninitialized loses an intentionally empty region.
Case contract
Commands act on finite sample indices [0,size). Save/restore includes the clip-enable bit; region edits update stored coverage even while clipping is disabled. Restore underflow is inert. Draw emits sorted effective samples.
Why this case matters
Raster clip state can leak coverage across draws even when every individual region is valid.
1 / The failure
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(commands, size):
full=set(range(size))
clip=set(full)
enabled=True
stack=[]
out=[]
for cmd in commands:
op=cmd[0]
mask=set(cmd[1]) & full if len(cmd)>1 else set()
if op=='save': stack.append((set(clip),enabled))
elif op=='restore':
if stack: clip,enabled=stack.pop()
elif op=='intersect': clip &= mask
elif op=='exclude': clip -= mask
elif op=='union': clip |= mask
elif op=='replace': clip=set(mask)
elif op=='invert': clip=full-clip
elif op=='reset': clip=set(full)
elif op=='disable': enabled=False
elif op=='enable': enabled=True; clip=set(full)
elif op=='draw': out.append(sorted(clip if enabled else full))
return out
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
if N == 1:
check('explicit sequence 0', solve([['replace', [0, 1, 2]], ['save'], ['exclude', [1]], ['draw'], ['restore'], ['draw']], 4), [[0, 2], [0, 1, 2]])
check('explicit sequence 1', solve([['replace', [0]], ['save'], ['replace', [1]], ['save'], ['replace', [2]], ['restore'], ['draw'], ['restore'], ['draw']], 4), [[1], [0]])
check('explicit sequence 2', solve([['replace', [0]], ['disable'], ['save'], ['enable'], ['restore'], ['draw']], 4), [[0, 1, 2, 3]])
check('explicit sequence 3', solve([['replace', [1, 2]], ['disable'], ['enable'], ['draw']], 4), [[1, 2]])
check('explicit sequence 4', solve([['replace', [0]], ['exclude', [2]], ['draw'], ['union', [0, 2]], ['draw']], 4), [[0], [0, 2]])
check('explicit sequence 5', solve([['replace', [1]], ['replace', [2]], ['draw'], ['invert'], ['draw'], ['reset'], ['draw']], 4), [[2], [0, 1, 3], [0, 1, 2, 3]])
check('explicit sequence 6', solve([['restore'], ['draw']], 4), [[0, 1, 2, 3]])
check('explicit sequence 7', solve([['replace', []], ['draw']], 4), [[]])
check('explicit sequence 8', solve([['disable'], ['replace', [0, 2, 8]], ['enable'], ['draw']], 4), [[0, 2]])
check('explicit sequence 9', solve([['reset'], ['replace', [0]], ['draw']], 4), [[0]])
check('explicit sequence 10', solve([['replace', []], ['disable'], ['enable'], ['draw']], 4), [[]])
if N == 2:
check('explicit sequence 0', solve([['replace', [0, 1, 2]], ['save'], ['exclude', [1]], ['draw'], ['restore'], ['draw']], 5), [[0, 2], [0, 1, 2]])
check('explicit sequence 1', solve([['replace', [0]], ['save'], ['replace', [1]], ['save'], ['replace', [2]], ['restore'], ['draw'], ['restore'], ['draw']], 5), [[1], [0]])
check('explicit sequence 2', solve([['replace', [0]], ['disable'], ['save'], ['enable'], ['restore'], ['draw']], 5), [[0, 1, 2, 3, 4]])
check('explicit sequence 3', solve([['replace', [1, 2]], ['disable'], ['enable'], ['draw']], 5), [[1, 2]])
check('explicit sequence 4', solve([['replace', [0]], ['exclude', [2]], ['draw'], ['union', [0, 2]], ['draw']], 5), [[0], [0, 2]])
check('explicit sequence 5', solve([['replace', [1]], ['replace', [2]], ['draw'], ['invert'], ['draw'], ['reset'], ['draw']], 5), [[2], [0, 1, 3, 4], [0, 1, 2, 3, 4]])
check('explicit sequence 6', solve([['restore'], ['draw']], 5), [[0, 1, 2, 3, 4]])
check('explicit sequence 7', solve([['replace', []], ['draw']], 5), [[]])
check('explicit sequence 8', solve([['disable'], ['replace', [0, 2, 8]], ['enable'], ['draw']], 5), [[0, 2]])
check('explicit sequence 9', solve([['reset'], ['replace', [0]], ['draw']], 5), [[0]])
check('explicit sequence 10', solve([['replace', []], ['disable'], ['enable'], ['draw']], 5), [[]])
if N == 3:
check('explicit sequence 0', solve([['replace', [0, 1, 2]], ['save'], ['exclude', [1]], ['draw'], ['restore'], ['draw']], 6), [[0, 2], [0, 1, 2]])
check('explicit sequence 1', solve([['replace', [0]], ['save'], ['replace', [1]], ['save'], ['replace', [2]], ['restore'], ['draw'], ['restore'], ['draw']], 6), [[1], [0]])
check('explicit sequence 2', solve([['replace', [0]], ['disable'], ['save'], ['enable'], ['restore'], ['draw']], 6), [[0, 1, 2, 3, 4, 5]])
check('explicit sequence 3', solve([['replace', [1, 2]], ['disable'], ['enable'], ['draw']], 6), [[1, 2]])
check('explicit sequence 4', solve([['replace', [0]], ['exclude', [2]], ['draw'], ['union', [0, 2]], ['draw']], 6), [[0], [0, 2]])
check('explicit sequence 5', solve([['replace', [1]], ['replace', [2]], ['draw'], ['invert'], ['draw'], ['reset'], ['draw']], 6), [[2], [0, 1, 3, 4, 5], [0, 1, 2, 3, 4, 5]])
check('explicit sequence 6', solve([['restore'], ['draw']], 6), [[0, 1, 2, 3, 4, 5]])
check('explicit sequence 7', solve([['replace', []], ['draw']], 6), [[]])
check('explicit sequence 8', solve([['disable'], ['replace', [0, 2, 8]], ['enable'], ['draw']], 6), [[0, 2]])
check('explicit sequence 9', solve([['reset'], ['replace', [0]], ['draw']], 6), [[0]])
check('explicit sequence 10', solve([['replace', []], ['disable'], ['enable'], ['draw']], 6), [[]])
if N == 4:
check('explicit sequence 0', solve([['replace', [0, 1, 2]], ['save'], ['exclude', [1]], ['draw'], ['restore'], ['draw']], 7), [[0, 2], [0, 1, 2]])
check('explicit sequence 1', solve([['replace', [0]], ['save'], ['replace', [1]], ['save'], ['replace', [2]], ['restore'], ['draw'], ['restore'], ['draw']], 7), [[1], [0]])
check('explicit sequence 2', solve([['replace', [0]], ['disable'], ['save'], ['enable'], ['restore'], ['draw']], 7), [[0, 1, 2, 3, 4, 5, 6]])
check('explicit sequence 3', solve([['replace', [1, 2]], ['disable'], ['enable'], ['draw']], 7), [[1, 2]])
check('explicit sequence 4', solve([['replace', [0]], ['exclude', [2]], ['draw'], ['union', [0, 2]], ['draw']], 7), [[0], [0, 2]])
check('explicit sequence 5', solve([['replace', [1]], ['replace', [2]], ['draw'], ['invert'], ['draw'], ['reset'], ['draw']], 7), [[2], [0, 1, 3, 4, 5, 6], [0, 1, 2, 3, 4, 5, 6]])
check('explicit sequence 6', solve([['restore'], ['draw']], 7), [[0, 1, 2, 3, 4, 5, 6]])
check('explicit sequence 7', solve([['replace', []], ['draw']], 7), [[]])
check('explicit sequence 8', solve([['disable'], ['replace', [0, 2, 8]], ['enable'], ['draw']], 7), [[0, 2]])
check('explicit sequence 9', solve([['reset'], ['replace', [0]], ['draw']], 7), [[0]])
check('explicit sequence 10', solve([['replace', []], ['disable'], ['enable'], ['draw']], 7), [[]])
if N == 5:
check('explicit sequence 0', solve([['replace', [0, 1, 2]], ['save'], ['exclude', [1]], ['draw'], ['restore'], ['draw']], 8), [[0, 2], [0, 1, 2]])
check('explicit sequence 1', solve([['replace', [0]], ['save'], ['replace', [1]], ['save'], ['replace', [2]], ['restore'], ['draw'], ['restore'], ['draw']], 8), [[1], [0]])
check('explicit sequence 2', solve([['replace', [0]], ['disable'], ['save'], ['enable'], ['restore'], ['draw']], 8), [[0, 1, 2, 3, 4, 5, 6, 7]])
check('explicit sequence 3', solve([['replace', [1, 2]], ['disable'], ['enable'], ['draw']], 8), [[1, 2]])
check('explicit sequence 4', solve([['replace', [0]], ['exclude', [2]], ['draw'], ['union', [0, 2]], ['draw']], 8), [[0], [0, 2]])
check('explicit sequence 5', solve([['replace', [1]], ['replace', [2]], ['draw'], ['invert'], ['draw'], ['reset'], ['draw']], 8), [[2], [0, 1, 3, 4, 5, 6, 7], [0, 1, 2, 3, 4, 5, 6, 7]])
check('explicit sequence 6', solve([['restore'], ['draw']], 8), [[0, 1, 2, 3, 4, 5, 6, 7]])
check('explicit sequence 7', solve([['replace', []], ['draw']], 8), [[]])
check('explicit sequence 8', solve([['disable'], ['replace', [0, 2, 8]], ['enable'], ['draw']], 8), [[0, 2]])
check('explicit sequence 9', solve([['reset'], ['replace', [0]], ['draw']], 8), [[0]])
check('explicit sequence 10', solve([['replace', []], ['disable'], ['enable'], ['draw']], 8), [[]])
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 fixture | Actual | Expected | Outcome |
|---|---|---|---|
| explicit sequence 0 | [[0, 2], [0, 1, 2]] | [[0, 2], [0, 1, 2]] | Passed |
| explicit sequence 1 | [[1], [0]] | [[1], [0]] | Passed |
| explicit sequence 2 | [[0, 1, 2, 3]] | [[0, 1, 2, 3]] | Passed |
| explicit sequence 3 | [[0, 1, 2, 3]] | [[1, 2]] | Failed |
| explicit sequence 4 | [[0], [0, 2]] | [[0], [0, 2]] | Passed |
| explicit sequence 5 | [[2], [0, 1, 3], [0, 1, 2, 3]] | [[2], [0, 1, 3], [0, 1, 2, 3]] | Passed |
| explicit sequence 6 | [[0, 1, 2, 3]] | [[0, 1, 2, 3]] | Passed |
| explicit sequence 7 | [[]] | [[]] | Passed |
| explicit sequence 8 | [[0, 1, 2, 3]] | [[0, 2]] | Failed |
| explicit sequence 9 | [[0]] | [[0]] | Passed |
| explicit sequence 10 | [[0, 1, 2, 3]] | [[]] | Failed |
SHA-256 / 7e25b0f47ba5f6594cf16590f7aaec020e4cde05204162cef055187457ad8f10
2 / The unsuccessful fix
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(commands, size):
full=set(range(size))
clip=set(full)
enabled=True
stack=[]
out=[]
for cmd in commands:
op=cmd[0]
mask=set(cmd[1]) & full if len(cmd)>1 else set()
if op=='save': stack.append((set(clip),enabled))
elif op=='restore':
if stack: clip,enabled=stack.pop()
elif op=='intersect': clip &= mask
elif op=='exclude': clip -= mask
elif op=='union': clip |= mask
elif op=='replace': clip=set(mask)
elif op=='invert': clip=full-clip
elif op=='reset': clip=set(full)
elif op=='disable': enabled=False
elif op=='enable': enabled=True; clip=clip or set(full)
elif op=='draw': out.append(sorted(clip if enabled else full))
return out
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
if N == 1:
check('explicit sequence 0', solve([['replace', [0, 1, 2]], ['save'], ['exclude', [1]], ['draw'], ['restore'], ['draw']], 4), [[0, 2], [0, 1, 2]])
check('explicit sequence 1', solve([['replace', [0]], ['save'], ['replace', [1]], ['save'], ['replace', [2]], ['restore'], ['draw'], ['restore'], ['draw']], 4), [[1], [0]])
check('explicit sequence 2', solve([['replace', [0]], ['disable'], ['save'], ['enable'], ['restore'], ['draw']], 4), [[0, 1, 2, 3]])
check('explicit sequence 3', solve([['replace', [1, 2]], ['disable'], ['enable'], ['draw']], 4), [[1, 2]])
check('explicit sequence 4', solve([['replace', [0]], ['exclude', [2]], ['draw'], ['union', [0, 2]], ['draw']], 4), [[0], [0, 2]])
check('explicit sequence 5', solve([['replace', [1]], ['replace', [2]], ['draw'], ['invert'], ['draw'], ['reset'], ['draw']], 4), [[2], [0, 1, 3], [0, 1, 2, 3]])
check('explicit sequence 6', solve([['restore'], ['draw']], 4), [[0, 1, 2, 3]])
check('explicit sequence 7', solve([['replace', []], ['draw']], 4), [[]])
check('explicit sequence 8', solve([['disable'], ['replace', [0, 2, 8]], ['enable'], ['draw']], 4), [[0, 2]])
check('explicit sequence 9', solve([['reset'], ['replace', [0]], ['draw']], 4), [[0]])
check('explicit sequence 10', solve([['replace', []], ['disable'], ['enable'], ['draw']], 4), [[]])
if N == 2:
check('explicit sequence 0', solve([['replace', [0, 1, 2]], ['save'], ['exclude', [1]], ['draw'], ['restore'], ['draw']], 5), [[0, 2], [0, 1, 2]])
check('explicit sequence 1', solve([['replace', [0]], ['save'], ['replace', [1]], ['save'], ['replace', [2]], ['restore'], ['draw'], ['restore'], ['draw']], 5), [[1], [0]])
check('explicit sequence 2', solve([['replace', [0]], ['disable'], ['save'], ['enable'], ['restore'], ['draw']], 5), [[0, 1, 2, 3, 4]])
check('explicit sequence 3', solve([['replace', [1, 2]], ['disable'], ['enable'], ['draw']], 5), [[1, 2]])
check('explicit sequence 4', solve([['replace', [0]], ['exclude', [2]], ['draw'], ['union', [0, 2]], ['draw']], 5), [[0], [0, 2]])
check('explicit sequence 5', solve([['replace', [1]], ['replace', [2]], ['draw'], ['invert'], ['draw'], ['reset'], ['draw']], 5), [[2], [0, 1, 3, 4], [0, 1, 2, 3, 4]])
check('explicit sequence 6', solve([['restore'], ['draw']], 5), [[0, 1, 2, 3, 4]])
check('explicit sequence 7', solve([['replace', []], ['draw']], 5), [[]])
check('explicit sequence 8', solve([['disable'], ['replace', [0, 2, 8]], ['enable'], ['draw']], 5), [[0, 2]])
check('explicit sequence 9', solve([['reset'], ['replace', [0]], ['draw']], 5), [[0]])
check('explicit sequence 10', solve([['replace', []], ['disable'], ['enable'], ['draw']], 5), [[]])
if N == 3:
check('explicit sequence 0', solve([['replace', [0, 1, 2]], ['save'], ['exclude', [1]], ['draw'], ['restore'], ['draw']], 6), [[0, 2], [0, 1, 2]])
check('explicit sequence 1', solve([['replace', [0]], ['save'], ['replace', [1]], ['save'], ['replace', [2]], ['restore'], ['draw'], ['restore'], ['draw']], 6), [[1], [0]])
check('explicit sequence 2', solve([['replace', [0]], ['disable'], ['save'], ['enable'], ['restore'], ['draw']], 6), [[0, 1, 2, 3, 4, 5]])
check('explicit sequence 3', solve([['replace', [1, 2]], ['disable'], ['enable'], ['draw']], 6), [[1, 2]])
check('explicit sequence 4', solve([['replace', [0]], ['exclude', [2]], ['draw'], ['union', [0, 2]], ['draw']], 6), [[0], [0, 2]])
check('explicit sequence 5', solve([['replace', [1]], ['replace', [2]], ['draw'], ['invert'], ['draw'], ['reset'], ['draw']], 6), [[2], [0, 1, 3, 4, 5], [0, 1, 2, 3, 4, 5]])
check('explicit sequence 6', solve([['restore'], ['draw']], 6), [[0, 1, 2, 3, 4, 5]])
check('explicit sequence 7', solve([['replace', []], ['draw']], 6), [[]])
check('explicit sequence 8', solve([['disable'], ['replace', [0, 2, 8]], ['enable'], ['draw']], 6), [[0, 2]])
check('explicit sequence 9', solve([['reset'], ['replace', [0]], ['draw']], 6), [[0]])
check('explicit sequence 10', solve([['replace', []], ['disable'], ['enable'], ['draw']], 6), [[]])
if N == 4:
check('explicit sequence 0', solve([['replace', [0, 1, 2]], ['save'], ['exclude', [1]], ['draw'], ['restore'], ['draw']], 7), [[0, 2], [0, 1, 2]])
check('explicit sequence 1', solve([['replace', [0]], ['save'], ['replace', [1]], ['save'], ['replace', [2]], ['restore'], ['draw'], ['restore'], ['draw']], 7), [[1], [0]])
check('explicit sequence 2', solve([['replace', [0]], ['disable'], ['save'], ['enable'], ['restore'], ['draw']], 7), [[0, 1, 2, 3, 4, 5, 6]])
check('explicit sequence 3', solve([['replace', [1, 2]], ['disable'], ['enable'], ['draw']], 7), [[1, 2]])
check('explicit sequence 4', solve([['replace', [0]], ['exclude', [2]], ['draw'], ['union', [0, 2]], ['draw']], 7), [[0], [0, 2]])
check('explicit sequence 5', solve([['replace', [1]], ['replace', [2]], ['draw'], ['invert'], ['draw'], ['reset'], ['draw']], 7), [[2], [0, 1, 3, 4, 5, 6], [0, 1, 2, 3, 4, 5, 6]])
check('explicit sequence 6', solve([['restore'], ['draw']], 7), [[0, 1, 2, 3, 4, 5, 6]])
check('explicit sequence 7', solve([['replace', []], ['draw']], 7), [[]])
check('explicit sequence 8', solve([['disable'], ['replace', [0, 2, 8]], ['enable'], ['draw']], 7), [[0, 2]])
check('explicit sequence 9', solve([['reset'], ['replace', [0]], ['draw']], 7), [[0]])
check('explicit sequence 10', solve([['replace', []], ['disable'], ['enable'], ['draw']], 7), [[]])
if N == 5:
check('explicit sequence 0', solve([['replace', [0, 1, 2]], ['save'], ['exclude', [1]], ['draw'], ['restore'], ['draw']], 8), [[0, 2], [0, 1, 2]])
check('explicit sequence 1', solve([['replace', [0]], ['save'], ['replace', [1]], ['save'], ['replace', [2]], ['restore'], ['draw'], ['restore'], ['draw']], 8), [[1], [0]])
check('explicit sequence 2', solve([['replace', [0]], ['disable'], ['save'], ['enable'], ['restore'], ['draw']], 8), [[0, 1, 2, 3, 4, 5, 6, 7]])
check('explicit sequence 3', solve([['replace', [1, 2]], ['disable'], ['enable'], ['draw']], 8), [[1, 2]])
check('explicit sequence 4', solve([['replace', [0]], ['exclude', [2]], ['draw'], ['union', [0, 2]], ['draw']], 8), [[0], [0, 2]])
check('explicit sequence 5', solve([['replace', [1]], ['replace', [2]], ['draw'], ['invert'], ['draw'], ['reset'], ['draw']], 8), [[2], [0, 1, 3, 4, 5, 6, 7], [0, 1, 2, 3, 4, 5, 6, 7]])
check('explicit sequence 6', solve([['restore'], ['draw']], 8), [[0, 1, 2, 3, 4, 5, 6, 7]])
check('explicit sequence 7', solve([['replace', []], ['draw']], 8), [[]])
check('explicit sequence 8', solve([['disable'], ['replace', [0, 2, 8]], ['enable'], ['draw']], 8), [[0, 2]])
check('explicit sequence 9', solve([['reset'], ['replace', [0]], ['draw']], 8), [[0]])
check('explicit sequence 10', solve([['replace', []], ['disable'], ['enable'], ['draw']], 8), [[]])
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 fixture | Actual | Expected | Outcome |
|---|---|---|---|
| explicit sequence 0 | [[0, 2], [0, 1, 2]] | [[0, 2], [0, 1, 2]] | Passed |
| explicit sequence 1 | [[1], [0]] | [[1], [0]] | Passed |
| explicit sequence 2 | [[0, 1, 2, 3]] | [[0, 1, 2, 3]] | Passed |
| explicit sequence 3 | [[1, 2]] | [[1, 2]] | Passed |
| explicit sequence 4 | [[0], [0, 2]] | [[0], [0, 2]] | Passed |
| explicit sequence 5 | [[2], [0, 1, 3], [0, 1, 2, 3]] | [[2], [0, 1, 3], [0, 1, 2, 3]] | Passed |
| explicit sequence 6 | [[0, 1, 2, 3]] | [[0, 1, 2, 3]] | Passed |
| explicit sequence 7 | [[]] | [[]] | Passed |
| explicit sequence 8 | [[0, 2]] | [[0, 2]] | Passed |
| explicit sequence 9 | [[0]] | [[0]] | Passed |
| explicit sequence 10 | [[0, 1, 2, 3]] | [[]] | Failed |
SHA-256 / 4d6b5767c18d2a90cbf6490cb11f5f28ce71040d4a9f61efb647f70dca8a1541
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.
Member access is invitation-based. Sign in with your invited account to inspect the repair.
Sign in to the archive ↗Verification & scope
Finite one-dimensional integer sample sets model coverage state only; no geometric intersection, memory layout, GPU or graphics-standard conformance is claimed. 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 2026-09-29T14:45:08.613636+00:00.
Case digest / 566843af170c3e90d08cffa680a6c01c5a09c474407d9ddc64ce1d1086c7398c