New diamond recursion defects (O(2^D) → O(N)): - godot-0009: Font::_is_cyclic no visited set — CJK fallback diamond, 2648x at F=4,D=8 - godot-0010: Font::_update_rids_fb no visited set — duplicate RIDs + O(N^2) hot path - meson-0002: get_internal_static_libraries_recurse link_whole guard missing — 132x at D=10 - typescript-0003: hasBaseType inner check() no visited set — 1024x at D=10; hot on instanceof New O(N²) defects: - typeorm-0004: SubjectTopologicalSorter Array.indexOf dedup — 200x at N=400 - typeorm-0005: DepGraph.createDFS result.indexOf + addDependency edge dedup — 300x at N=600 CLEAN confirmed (diamond recursion sweep): bazel, cargo, cmake, composer, dgl, diesel, doctrine-orm, efcore, helm, mybatis, networkx-deeper, ninja, npm-arborist, peewee, pip, rubygems, seaorm, sqlalchemy, swift UNDF: 571→578 assigned; MOAD count: 629→635
18 lines
847 B
Markdown
18 lines
847 B
Markdown
## Diamond Recursion Scan — Deeper Scan Notes
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**Scan date:** 2026-03-29
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**Pattern:** Recursive cycle/dependency check without visited set (CWE-407 diamond recursion, O(2^D))
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### Summary
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**nx-0001 (existing)** covers `recursive_simple_cycles` B defaultdict(list) O(N²).
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**nx-0002 (existing)** covers `all_node_cuts` seen-list O(K²).
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### Additional functions checked — CLEAN
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- `dag.py descendants/ancestors`: uses `bfs_edges` which employs a visited set internally — CLEAN.
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- `dag.py has_cycle`: uses `topological_generations` which is iterative with a visited set — CLEAN.
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- `algorithms/chains.py chain_decomposition`: uses explicit `visited = set()` — CLEAN.
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- All other DAG algorithms in `networkx/algorithms/dag.py` use proper visited sets.
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### Verdict: No additional diamond recursion defects found beyond nx-0001 and nx-0002
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