{"abstract":"Dead-result elimination deletes a volatile read.","category":"Compiler transformation correctness","checks":7,"contract":"Return retained instruction IDs in order. Instructions have (id, live, effect), where effect is pure, write, volatile or trap; only unused pure operations may be removed.","contract_signature":"ops","evaluation_group":"model-50a70a3a116bd299","failed_approach":"Retaining writes alone still removes volatile reads and trapping instructions.","family":"z-compilers-dead-effects","id":"FA-11446","implementations":{"attempt":{"sha256":"318f6512259e87a43ed423e182e3d96c9d4603df2cee667e6aadae5b6969b4dd","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(ops):\n    return [i for i, live, effect in ops if live or effect == 'write']\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('empty', solve([]), [])\ncheck('dead pure', solve([(N,False,'pure')]), [])\ncheck('live pure', solve([(N,True,'pure')]), [N])\ncheck('write', solve([(N,False,'write')]), [N])\ncheck('volatile', solve([(N,False,'volatile')]), [N])\ncheck('trap', solve([(N,False,'trap')]), [N])\ncheck('preserve order', solve([(N,False,'write'),(N+1,False,'pure'),(N+2,True,'pure')]), [N,N+2])\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":"12ba8d22515b8d8bcd0ea135e98ece94363b6c25c0310a2216054e04ce6f8379","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(ops):\n    return [i for i, live, effect in ops if live]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('empty', solve([]), [])\ncheck('dead pure', solve([(N,False,'pure')]), [])\ncheck('live pure', solve([(N,True,'pure')]), [N])\ncheck('write', solve([(N,False,'write')]), [N])\ncheck('volatile', solve([(N,False,'volatile')]), [N])\ncheck('trap', solve([(N,False,'trap')]), [N])\ncheck('preserve order', solve([(N,False,'write'),(N+1,False,'pure'),(N+2,True,'pure')]), [N,N+2])\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":"z-compilers-dead-effects","generated_at":"2026-09-29T14:38:48.025717+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A deterministic miniature compiler-pass model; inputs are explicit IR facts, not a production compiler.","root_cause":"Result liveness is treated as the only reason to retain an instruction.","sha256":"3d4d620f6d62004a6ccb6b1373fb558f7b9bcd072d0b954ab5641fccbf6f4d0b","title":"Dead-result elimination deletes a volatile read · 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":39.324,"exit_code":1,"observations":[{"actual":[],"check":"empty","expected":[],"passed":true},{"actual":[],"check":"dead pure","expected":[],"passed":true},{"actual":[1],"check":"live pure","expected":[1],"passed":true},{"actual":[1],"check":"write","expected":[1],"passed":true},{"actual":[],"check":"volatile","expected":[1],"passed":false},{"actual":[],"check":"trap","expected":[1],"passed":false},{"actual":[1,3],"check":"preserve order","expected":[1,3],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"empty\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"dead pure\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"live pure\", \"actual\": [1], \"expected\": [1], \"passed\": true}, {\"check\": \"write\", \"actual\": [1], \"expected\": [1], \"passed\": true}, {\"check\": \"volatile\", \"actual\": [], \"expected\": [1], \"passed\": false}, {\"check\": \"trap\", \"actual\": [], \"expected\": [1], \"passed\": false}, {\"check\": \"preserve order\", \"actual\": [1, 3], \"expected\": [1, 3], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":38.672,"exit_code":1,"observations":[{"actual":[],"check":"empty","expected":[],"passed":true},{"actual":[],"check":"dead pure","expected":[],"passed":true},{"actual":[1],"check":"live pure","expected":[1],"passed":true},{"actual":[],"check":"write","expected":[1],"passed":false},{"actual":[],"check":"volatile","expected":[1],"passed":false},{"actual":[],"check":"trap","expected":[1],"passed":false},{"actual":[3],"check":"preserve order","expected":[1,3],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"empty\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"dead pure\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"live pure\", \"actual\": [1], \"expected\": [1], \"passed\": true}, {\"check\": \"write\", \"actual\": [], \"expected\": [1], \"passed\": false}, {\"check\": \"volatile\", \"actual\": [], \"expected\": [1], \"passed\": false}, {\"check\": \"trap\", \"actual\": [], \"expected\": [1], \"passed\": false}, {\"check\": \"preserve order\", \"actual\": [3], \"expected\": [1, 3], \"passed\": false}], \"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."}}