{"abstract":"Packed-row addressing reads alignment padding as pixels in subsequent rows.","category":"Raster memory layout","checks":4,"contract":"Extract height rows of width scalar pixels from a sufficiently large flat buffer with stride>=width; padding is not image data.","evaluation_group":"xg-row-stride-addressing","failed_approach":"Using stride for row length includes padding in each returned image row.","family":"xg-row-stride-addressing","id":"FA-10731","implementations":{"attempt":{"sha256":"247775a20b36eb47d3f8b3697369c4ac373c75421a66195bdfc75f766addbd43","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(pixels, width, height, stride):\n    return [pixels[y*stride:y*stride+stride] for y in range(height)]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve(*([1, 2, 99, 3, 4, 99], 2, 2, 3)), [[1, 2], [3, 4]])\ncheck('fixture 2', solve(*([1, 2], 2, 1, 2)), [[1, 2]])\ncheck('fixture 3', solve(*([], 0, 0, 0)), [])\ncheck('fixture 4', solve(*([1, 99, 2, 99], 1, 2, 2)), [[1], [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":"fb855b8414f1ce7d885c88b757571cb2302d302c77235391d533efe380fc34a5","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(pixels, width, height, stride):\n    return [pixels[y*width:y*width+width] for y in range(height)]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve(*([1, 2, 99, 3, 4, 99], 2, 2, 3)), [[1, 2], [3, 4]])\ncheck('fixture 2', solve(*([1, 2], 2, 1, 2)), [[1, 2]])\ncheck('fixture 3', solve(*([], 0, 0, 0)), [])\ncheck('fixture 4', solve(*([1, 99, 2, 99], 1, 2, 2)), [[1], [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"},"fixed":{"sha256":"ad8cc5a16b402d3f8039e58f350a9864279429124c3b7676974f08e4cd420032","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(pixels, width, height, stride):\n    return [pixels[y*stride:y*stride+width] for y in range(height)]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve(*([1, 2, 99, 3, 4, 99], 2, 2, 3)), [[1, 2], [3, 4]])\ncheck('fixture 2', solve(*([1, 2], 2, 1, 2)), [[1, 2]])\ncheck('fixture 3', solve(*([], 0, 0, 0)), [])\ncheck('fixture 4', solve(*([1, 99, 2, 99], 1, 2, 2)), [[1], [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":"xg-row-stride-addressing","generated_at":"2026-09-29T14:38:41.714072+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.","repair":"Use the stage contract: Extract height rows of width scalar pixels from a sufficiently large flat buffer with stride>=width; padding is not image data.","root_cause":"Packed-row addressing reads alignment padding as pixels in subsequent rows.","sha256":"d0f54cabebd57895d64cfb55ffc74cb1f922cc97426bc9c6717819b7a1b6c6c1","title":"Row stride addressing · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":36.684,"exit_code":1,"observations":[{"actual":[[1,2,99],[3,4,99]],"check":"fixture 1","expected":[[1,2],[3,4]],"passed":false},{"actual":[[1,2]],"check":"fixture 2","expected":[[1,2]],"passed":true},{"actual":[],"check":"fixture 3","expected":[],"passed":true},{"actual":[[1,99],[2,99]],"check":"fixture 4","expected":[[1],[2]],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [[1, 2, 99], [3, 4, 99]], \"expected\": [[1, 2], [3, 4]], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [[1, 2]], \"expected\": [[1, 2]], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [[1, 99], [2, 99]], \"expected\": [[1], [2]], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":36.627,"exit_code":1,"observations":[{"actual":[[1,2],[99,3]],"check":"fixture 1","expected":[[1,2],[3,4]],"passed":false},{"actual":[[1,2]],"check":"fixture 2","expected":[[1,2]],"passed":true},{"actual":[],"check":"fixture 3","expected":[],"passed":true},{"actual":[[1],[99]],"check":"fixture 4","expected":[[1],[2]],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [[1, 2], [99, 3]], \"expected\": [[1, 2], [3, 4]], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [[1, 2]], \"expected\": [[1, 2]], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [[1], [99]], \"expected\": [[1], [2]], \"passed\": false}], \"passed\": false}\n"},"fixed":{"elapsed_ms":36.725,"exit_code":0,"observations":[{"actual":[[1,2],[3,4]],"check":"fixture 1","expected":[[1,2],[3,4]],"passed":true},{"actual":[[1,2]],"check":"fixture 2","expected":[[1,2]],"passed":true},{"actual":[],"check":"fixture 3","expected":[],"passed":true},{"actual":[[1],[2]],"check":"fixture 4","expected":[[1],[2]],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [[1, 2], [3, 4]], \"expected\": [[1, 2], [3, 4]], \"passed\": true}, {\"check\": \"fixture 2\", \"actual\": [[1, 2]], \"expected\": [[1, 2]], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [[1], [2]], \"expected\": [[1], [2]], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}