{"abstract":"The restart sentinel is consumed as an ordinary vertex index.","category":"Rendering state","checks":4,"contract":"Split an index buffer into nonempty primitive runs at a configured restart sentinel. Restart markers are not vertices; consecutive markers produce no empty runs.","contract_signature":"indices, restart","evaluation_group":"xg-primitive-restart-index-separation","failed_approach":"Deleting sentinels without splitting joins otherwise independent primitives.","family":"xg-primitive-restart-index-separation","id":"FA-10776","implementations":{"attempt":{"sha256":"0f81e785c06416a5ad2b52bedd6194ab37ad0bb605ea6e7c408eda23a1d7f70a","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(indices, restart):\n    return [[x for x in indices if x!=restart]] if indices else []\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve(*([0, 1, 99, 2, 3], 99)), [[0, 1], [2, 3]])\ncheck('fixture 2', solve(*([99, 0, 99, 99], 99)), [[0]])\ncheck('fixture 3', solve(*([], 99)), [])\ncheck('fixture 4', solve(*([0, 1], 99)), [[0, 1]])\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":"fbc79fc7bb61e00987e1c2a4cad1dda3c3b473510ca4e0b9667ea33dd8df8b3e","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(indices, restart):\n    return [list(indices)] if indices else []\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve(*([0, 1, 99, 2, 3], 99)), [[0, 1], [2, 3]])\ncheck('fixture 2', solve(*([99, 0, 99, 99], 99)), [[0]])\ncheck('fixture 3', solve(*([], 99)), [])\ncheck('fixture 4', solve(*([0, 1], 99)), [[0, 1]])\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":" 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":"xg-primitive-restart-index-separation","generated_at":"2026-09-29T14:38:42.089309+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A deterministic software graphics stage with explicit channel and coordinate conventions; no hardware, device profile or API behavior is inferred.","root_cause":"The restart sentinel is consumed as an ordinary vertex index.","sha256":"c48846b0d79da8980a572f5cf1055960bc6986990abcdaf2e9ea0901273539ab","title":"Primitive restart index separation · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":40.616,"exit_code":1,"observations":[{"actual":[[0,1,2,3]],"check":"fixture 1","expected":[[0,1],[2,3]],"passed":false},{"actual":[[0]],"check":"fixture 2","expected":[[0]],"passed":true},{"actual":[],"check":"fixture 3","expected":[],"passed":true},{"actual":[[0,1]],"check":"fixture 4","expected":[[0,1]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [[0, 1, 2, 3]], \"expected\": [[0, 1], [2, 3]], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [[0]], \"expected\": [[0]], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [[0, 1]], \"expected\": [[0, 1]], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":39.148,"exit_code":1,"observations":[{"actual":[[0,1,99,2,3]],"check":"fixture 1","expected":[[0,1],[2,3]],"passed":false},{"actual":[[99,0,99,99]],"check":"fixture 2","expected":[[0]],"passed":false},{"actual":[],"check":"fixture 3","expected":[],"passed":true},{"actual":[[0,1]],"check":"fixture 4","expected":[[0,1]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [[0, 1, 99, 2, 3]], \"expected\": [[0, 1], [2, 3]], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [[99, 0, 99, 99]], \"expected\": [[0]], \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [[0, 1]], \"expected\": [[0, 1]], \"passed\": true}], \"passed\": false}\n"}},"member_only":{"stages":["fixed"],"fields":["implementations.fixed","verification.fixed","harness","repair"],"note":"The verified repair, its recorded checks, the repair description, and the scoring harness are available to members."}}