{"abstract":"Reader consumes the sync prefix as a sample field.","category":"PCM sample encoding","checks":8,"contract":"Read up to declared unsigned packed fields after a bit prefix; incomplete fields are ignored, and report cursor in bits from packet start.","evaluation_group":"s3-pcm-subbyte-code-reader","failed_approach":"Treating a bit offset as an octet count starts inside sync.","family":"s3-pcm-subbyte-code-reader-prefix-consumption","id":"FA-48866","implementations":{"attempt":{"sha256":"9f4fa0f55b8768dc502a190b34357b0d27f61de51c2a0b65f4e1de5bf2dbfdda","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(octets, width, count, prefix_bits):\n    bits = [(byte >> (7-j)) & 1 for byte in octets for j in range(8)]\n    bits = bits[prefix_bits//8:]\n    available = len(bits)//width\n    count = min(count,available)\n    values=[]\n    for i in range(count):\n        values.append(sum(bits[i*width+j] << (width-1-j) for j in range(width)))\n    consumed = prefix_bits+count*width\n    return [values,consumed]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('oracle 1', solve(*([179, 144], 3, 3, 2)), [[6, 3, 4], 11])\ncheck('oracle 2', solve(*([255], 2, 2, 0)), [[3, 3], 4])\ncheck('oracle 3', solve(*([0], 1, 8, 0)), [[0, 0, 0, 0, 0, 0, 0, 0], 8])\ncheck('oracle 4', solve(*([], 3, 0, 0)), [[], 0])\ncheck('oracle 5', solve(*([160], 3, 1, 1)), [[2], 4])\ncheck('oracle 6', solve(*([18, 52], 4, 2, 4)), [[2, 3], 12])\ncheck('oracle 7', solve(*([255], 3, 5, 1)), [[7, 7], 7])\nif N == 1: check('variant packet 1', solve(*[[179, 144, 179, 144], 3, 6, 2]), [[6, 3, 4, 4, 1, 3], 20])\nif N == 2: check('variant packet 2', solve(*[[179, 144, 179, 144, 179, 144], 3, 9, 2]), [[6, 3, 4, 4, 1, 3, 1, 6, 2], 29])\nif N == 3: check('variant packet 3', solve(*[[179, 144, 179, 144, 179, 144, 179, 144], 3, 12, 2]), [[6, 3, 4, 4, 1, 3, 1, 6, 2, 0, 5, 4], 38])\nif N == 4: check('variant packet 4', solve(*[[179, 144, 179, 144, 179, 144, 179, 144, 179, 144], 3, 15, 2]), [[6, 3, 4, 4, 1, 3, 1, 6, 2, 0, 5, 4, 7, 1, 0], 47])\nif N == 5: check('variant packet 5', solve(*[[179, 144, 179, 144, 179, 144, 179, 144, 179, 144, 179, 144], 3, 18, 2]), [[6, 3, 4, 4, 1, 3, 1, 6, 2, 0, 5, 4, 7, 1, 0, 2, 6, 3], 56])\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"b32c8982d8a0bcb07a2890cdf10f10d0c5032d071891529f48efac5dd317b742","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(octets, width, count, prefix_bits):\n    bits = [(byte >> (7-j)) & 1 for byte in octets for j in range(8)]\n    bits = bits[:]\n    available = len(bits)//width\n    count = min(count,available)\n    values=[]\n    for i in range(count):\n        values.append(sum(bits[i*width+j] << (width-1-j) for j in range(width)))\n    consumed = prefix_bits+count*width\n    return [values,consumed]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('oracle 1', solve(*([179, 144], 3, 3, 2)), [[6, 3, 4], 11])\ncheck('oracle 2', solve(*([255], 2, 2, 0)), [[3, 3], 4])\ncheck('oracle 3', solve(*([0], 1, 8, 0)), [[0, 0, 0, 0, 0, 0, 0, 0], 8])\ncheck('oracle 4', solve(*([], 3, 0, 0)), [[], 0])\ncheck('oracle 5', solve(*([160], 3, 1, 1)), [[2], 4])\ncheck('oracle 6', solve(*([18, 52], 4, 2, 4)), [[2, 3], 12])\ncheck('oracle 7', solve(*([255], 3, 5, 1)), [[7, 7], 7])\nif N == 1: check('variant packet 1', solve(*[[179, 144, 179, 144], 3, 6, 2]), [[6, 3, 4, 4, 1, 3], 20])\nif N == 2: check('variant packet 2', solve(*[[179, 144, 179, 144, 179, 144], 3, 9, 2]), [[6, 3, 4, 4, 1, 3, 1, 6, 2], 29])\nif N == 3: check('variant packet 3', solve(*[[179, 144, 179, 144, 179, 144, 179, 144], 3, 12, 2]), [[6, 3, 4, 4, 1, 3, 1, 6, 2, 0, 5, 4], 38])\nif N == 4: check('variant packet 4', solve(*[[179, 144, 179, 144, 179, 144, 179, 144, 179, 144], 3, 15, 2]), [[6, 3, 4, 4, 1, 3, 1, 6, 2, 0, 5, 4, 7, 1, 0], 47])\nif N == 5: check('variant packet 5', solve(*[[179, 144, 179, 144, 179, 144, 179, 144, 179, 144, 179, 144], 3, 18, 2]), [[6, 3, 4, 4, 1, 3, 1, 6, 2, 0, 5, 4, 7, 1, 0, 2, 6, 3], 56])\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"fixed":{"sha256":"cd726691cc1aff69384aab8691bb0919dabb00a31cadcbed47a90409541c3525","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(octets, width, count, prefix_bits):\n    bits = [(byte >> (7-j)) & 1 for byte in octets for j in range(8)]\n    bits = bits[prefix_bits:]\n    available = len(bits)//width\n    count = min(count,available)\n    values=[]\n    for i in range(count):\n        values.append(sum(bits[i*width+j] << (width-1-j) for j in range(width)))\n    consumed = prefix_bits+count*width\n    return [values,consumed]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('oracle 1', solve(*([179, 144], 3, 3, 2)), [[6, 3, 4], 11])\ncheck('oracle 2', solve(*([255], 2, 2, 0)), [[3, 3], 4])\ncheck('oracle 3', solve(*([0], 1, 8, 0)), [[0, 0, 0, 0, 0, 0, 0, 0], 8])\ncheck('oracle 4', solve(*([], 3, 0, 0)), [[], 0])\ncheck('oracle 5', solve(*([160], 3, 1, 1)), [[2], 4])\ncheck('oracle 6', solve(*([18, 52], 4, 2, 4)), [[2, 3], 12])\ncheck('oracle 7', solve(*([255], 3, 5, 1)), [[7, 7], 7])\nif N == 1: check('variant packet 1', solve(*[[179, 144, 179, 144], 3, 6, 2]), [[6, 3, 4, 4, 1, 3], 20])\nif N == 2: check('variant packet 2', solve(*[[179, 144, 179, 144, 179, 144], 3, 9, 2]), [[6, 3, 4, 4, 1, 3, 1, 6, 2], 29])\nif N == 3: check('variant packet 3', solve(*[[179, 144, 179, 144, 179, 144, 179, 144], 3, 12, 2]), [[6, 3, 4, 4, 1, 3, 1, 6, 2, 0, 5, 4], 38])\nif N == 4: check('variant packet 4', solve(*[[179, 144, 179, 144, 179, 144, 179, 144, 179, 144], 3, 15, 2]), [[6, 3, 4, 4, 1, 3, 1, 6, 2, 0, 5, 4, 7, 1, 0], 47])\nif N == 5: check('variant packet 5', solve(*[[179, 144, 179, 144, 179, 144, 179, 144, 179, 144, 179, 144], 3, 18, 2]), [[6, 3, 4, 4, 1, 3, 1, 6, 2, 0, 5, 4, 7, 1, 0, 2, 6, 3], 56])\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":"Stipulated finite model; no claim of hardware timing or full file-format conformance. 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.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"s3-pcm-subbyte-code-reader-prefix-consumption","generated_at":"2026-09-29T14:44:54.652210+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Offline PCM interchange uses these exact bounded packet and sample representation decisions.","repair":"Use the stated conversion contract at prefix consumption.","root_cause":"Reader consumes the sync prefix as a sample field.","sha256":"51e70f3ecd05f522e7e218aa24cd6c60d0698746c11b6b3619bf6783ec29d1c1","title":"Subbyte code reader: prefix consumption · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":37.845,"exit_code":1,"observations":[{"actual":[[5,4,7],11],"check":"oracle 1","expected":[[6,3,4],11],"passed":false},{"actual":[[3,3],4],"check":"oracle 2","expected":[[3,3],4],"passed":true},{"actual":[[0,0,0,0,0,0,0,0],8],"check":"oracle 3","expected":[[0,0,0,0,0,0,0,0],8],"passed":true},{"actual":[[],0],"check":"oracle 4","expected":[[],0],"passed":true},{"actual":[[5],4],"check":"oracle 5","expected":[[2],4],"passed":false},{"actual":[[1,2],12],"check":"oracle 6","expected":[[2,3],12],"passed":false},{"actual":[[7,7],7],"check":"oracle 7","expected":[[7,7],7],"passed":true},{"actual":[[5,4,7,1,0,2],20],"check":"variant packet 1","expected":[[6,3,4,4,1,3],20],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"oracle 1\", \"actual\": [[5, 4, 7], 11], \"expected\": [[6, 3, 4], 11], \"passed\": false}, {\"check\": \"oracle 2\", \"actual\": [[3, 3], 4], \"expected\": [[3, 3], 4], \"passed\": true}, {\"check\": \"oracle 3\", \"actual\": [[0, 0, 0, 0, 0, 0, 0, 0], 8], \"expected\": [[0, 0, 0, 0, 0, 0, 0, 0], 8], \"passed\": true}, {\"check\": \"oracle 4\", \"actual\": [[], 0], \"expected\": [[], 0], \"passed\": true}, {\"check\": \"oracle 5\", \"actual\": [[5], 4], \"expected\": [[2], 4], \"passed\": false}, {\"check\": \"oracle 6\", \"actual\": [[1, 2], 12], \"expected\": [[2, 3], 12], \"passed\": false}, {\"check\": \"oracle 7\", \"actual\": [[7, 7], 7], \"expected\": [[7, 7], 7], \"passed\": true}, {\"check\": \"variant packet 1\", \"actual\": [[5, 4, 7, 1, 0, 2], 20], \"expected\": [[6, 3, 4, 4, 1, 3], 20], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":38.681,"exit_code":1,"observations":[{"actual":[[5,4,7],11],"check":"oracle 1","expected":[[6,3,4],11],"passed":false},{"actual":[[3,3],4],"check":"oracle 2","expected":[[3,3],4],"passed":true},{"actual":[[0,0,0,0,0,0,0,0],8],"check":"oracle 3","expected":[[0,0,0,0,0,0,0,0],8],"passed":true},{"actual":[[],0],"check":"oracle 4","expected":[[],0],"passed":true},{"actual":[[5],4],"check":"oracle 5","expected":[[2],4],"passed":false},{"actual":[[1,2],12],"check":"oracle 6","expected":[[2,3],12],"passed":false},{"actual":[[7,7],7],"check":"oracle 7","expected":[[7,7],7],"passed":true},{"actual":[[5,4,7,1,0,2],20],"check":"variant packet 1","expected":[[6,3,4,4,1,3],20],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"oracle 1\", \"actual\": [[5, 4, 7], 11], \"expected\": [[6, 3, 4], 11], \"passed\": false}, {\"check\": \"oracle 2\", \"actual\": [[3, 3], 4], \"expected\": [[3, 3], 4], \"passed\": true}, {\"check\": \"oracle 3\", \"actual\": [[0, 0, 0, 0, 0, 0, 0, 0], 8], \"expected\": [[0, 0, 0, 0, 0, 0, 0, 0], 8], \"passed\": true}, {\"check\": \"oracle 4\", \"actual\": [[], 0], \"expected\": [[], 0], \"passed\": true}, {\"check\": \"oracle 5\", \"actual\": [[5], 4], \"expected\": [[2], 4], \"passed\": false}, {\"check\": \"oracle 6\", \"actual\": [[1, 2], 12], \"expected\": [[2, 3], 12], \"passed\": false}, {\"check\": \"oracle 7\", \"actual\": [[7, 7], 7], \"expected\": [[7, 7], 7], \"passed\": true}, {\"check\": \"variant packet 1\", \"actual\": [[5, 4, 7, 1, 0, 2], 20], \"expected\": [[6, 3, 4, 4, 1, 3], 20], \"passed\": false}], \"passed\": false}\n"},"fixed":{"elapsed_ms":37.422,"exit_code":0,"observations":[{"actual":[[6,3,4],11],"check":"oracle 1","expected":[[6,3,4],11],"passed":true},{"actual":[[3,3],4],"check":"oracle 2","expected":[[3,3],4],"passed":true},{"actual":[[0,0,0,0,0,0,0,0],8],"check":"oracle 3","expected":[[0,0,0,0,0,0,0,0],8],"passed":true},{"actual":[[],0],"check":"oracle 4","expected":[[],0],"passed":true},{"actual":[[2],4],"check":"oracle 5","expected":[[2],4],"passed":true},{"actual":[[2,3],12],"check":"oracle 6","expected":[[2,3],12],"passed":true},{"actual":[[7,7],7],"check":"oracle 7","expected":[[7,7],7],"passed":true},{"actual":[[6,3,4,4,1,3],20],"check":"variant packet 1","expected":[[6,3,4,4,1,3],20],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"oracle 1\", \"actual\": [[6, 3, 4], 11], \"expected\": [[6, 3, 4], 11], \"passed\": true}, {\"check\": \"oracle 2\", \"actual\": [[3, 3], 4], \"expected\": [[3, 3], 4], \"passed\": true}, {\"check\": \"oracle 3\", \"actual\": [[0, 0, 0, 0, 0, 0, 0, 0], 8], \"expected\": [[0, 0, 0, 0, 0, 0, 0, 0], 8], \"passed\": true}, {\"check\": \"oracle 4\", \"actual\": [[], 0], \"expected\": [[], 0], \"passed\": true}, {\"check\": \"oracle 5\", \"actual\": [[2], 4], \"expected\": [[2], 4], \"passed\": true}, {\"check\": \"oracle 6\", \"actual\": [[2, 3], 12], \"expected\": [[2, 3], 12], \"passed\": true}, {\"check\": \"oracle 7\", \"actual\": [[7, 7], 7], \"expected\": [[7, 7], 7], \"passed\": true}, {\"check\": \"variant packet 1\", \"actual\": [[6, 3, 4, 4, 1, 3], 20], \"expected\": [[6, 3, 4, 4, 1, 3], 20], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}