Aug 2026· International Conference on Automated Software Engineering· Vol 33· 0 citations· 55 references
TL;DR
StructFix is proposed, a structure-aware APR framework that grounds masked patch generation in Code Property Graphs (CPGs), and explicitly coupling structural dependencies with masked generation improves repair effectiveness and enables transfer across datasets.
Abstract
Masked language models are increasingly used as the backbone of patch generation for automated program repair (APR). However, most Pre-trained Language Model (PLM)-based repair systems treat code as token sequences, underutilizing structural cues such as control and data dependencies. Consequently, they can produce test-passing patches that are not fully consistent with the intended behavior. We propose StructFix, a structure-aware APR framework that grounds masked patch generation in Code Property Graphs (CPGs). StructFix constructs method-level CPGs from the unmasked program context, encodes structural dependencies with a graph encoder, and integrates graph evidence into token representations through span-based token–node soft alignment and token-wise gated graph–text fusion. This design enables the model to use structural signals in a context-dependent manner while predicting masked tokens. StructFix correctly repairs 86 Defects4J v1.2 bugs, including 12 not repaired by any compared baseline, and repairs 30 Java and 28 Python defects on QuixBugs, which demonstrates cross-language robustness. Our experimental results show that explicitly coupling structural dependencies with masked generation improves repair effectiveness and enables transfer across datasets.
GraphAlignCoder is introduced, a training framework that transfers explicit correctness structure into code generation and consistently outperforms the base model, code-only SFT, and CodeRL across all benchmarks.
Yueke Zhang, Zihan Fang, Kevin Leach et al.· 0 citations
Large language models (LLMs) have improved automated program repair (APR), but two limitations remain. First, raw execution traces are often too large and repetitive to serve as effective model context. Second, repeated patch sampling may produce different implementations without yielding distinct root-cause hypotheses or repair strategies. We present CT-Repair, an agentic APR framework representing static and dynamic evidence as queryable Code Property Graph (CPG) and Temporal Execution Graph (TEG). CT-Repair applies a three-stage filtering pipeline to construct compact TEGs. Three finite-state-machine-guided agents analyze each bug from static, dynamic, and hybrid perspectives and independently produce evidence-grounded repair strategies. A strategy-guided generation procedure instantiates these strategies as candidate patches and uses validation feedback to refine the most promising strategy. We evaluate CT-Repair on 854 Java bugs from Defects4J v3.0. In the mixed-model configuration, CT-Repair correctly repairs 489 bugs. Under a controlled GPT-5.4-mini configuration, it repairs 388 bugs, 19 and 30 more than ReinFix and RepairAgent, respectively. The union of the three evidence perspectives repairs 99 more bugs than the strongest individual perspective. The filtering pipeline also compacts runtime evidence, with execution filtering narrowing the candidate method scope by 94.85% on average and behavior filtering further reducing retained runtime records by 55.97%. These results show that structured runtime evidence and multi-perspective reasoning can improve repair effectiveness without relying solely on a larger patch-generation budget.
Self-supervised automated program repair (APR) leverages project-specific perturbations to generate training data and uses test execution diagnostics to guide patch generation. In practice, however, diagnostics are heterogeneous (e.g., exception messages, stack traces, assertion diffs, and dynamic execution signals) and must fit within a strict context budget. Naive concatenation either truncates critical evidence or amplifies noisy artifacts, especially for deep bugs where the failure symptom is far from the root cause. We present TraceStructRepair, a diagnostic structuring and budgeting approach for execution-aware self-supervised APR. TraceStructRepair (1) extracts a compact set of execution diagnostics from a single failing test, including exception type and message, stack trace frames, assertion diffs, and optionally dynamically loaded classes; (2) normalizes and ranks diagnostic elements to reduce redundancy and framework noise; and (3) assembles a field-aware representation under a fixed token budget with per-field caps and lexicographic priority rules. We implement TraceStructRepair on top of the SelfAPR pipeline and evaluate it on Defects4J using a project-wise heldout protocol. Beyond end-to-end repair outcomes, we analyze robustness under noisy fault localization and component ablations. We release artifacts to facilitate replication and future work on execution-aware, budget-constrained APR.
Pan Lu, Dongcheng Li, W. E. Wong· Annual International Compute...· 0 citations
Automated Program Repair (APR) has recently benefited from Large Language Models (LLMs), yet their effectiveness heavily depends on repair context. Existing LLM-based APR methods suffer from a causality gap: test contexts can be noisy or incomplete, while source contexts derived from static analysis often contain irrelevant and unexecuted code, misleading LLMs from identifying the true root cause. To address this issue, we propose CausalRepair, a conversation-driven APR framework based on minimal causal context, i.e., the essential dependencies required to explain a failure. CausalRepair employs a dual-slicing strategy: context-aware static slicing purifies test semantics, while execution-trace-based dynamic slicing captures precise runtime dependencies in source code. Together, they construct compact, causally relevant contexts to guide iterative repair. We evaluate CausalRepair on Defects4J V1.2, V2.0, and Defects4J-Trans using DeepSeek-V3. CausalRepair correctly fixes 313 bugs on Defects4J, outperforming state-of-the-art approaches such as ReinFix and TSAPR, while reducing the average repair cost to $0.029 per bug.
Linhao Wu, Yizhou Chen, Zhenyu Yang et al.· 0 citations
LLM-based software engineering agents are constrained by limited context windows: roughly 100K tokens must store structurally relevant code subsets to resolve bugs. Standard retrieval models treat code as plain text, forcing agents to resolve multi-hop dependencies including subclass chains, transitive callers and interface implementations through slow trial and error. We tackle this limitation with lossless knowledge compression, encoding source code into an OWL2 ontology to answer structural queries using minimal relevant code fragments. We present OwlPath, an OWL2 reasoning layer atop CodeGraph, a widely used code intelligence platform with 500K+ GitHub stars, offering a unified CLI for structural code retrieval. Powered by tree-sitter parsing, OwlPath supports multi-language repositories (Python, JavaScript, TypeScript, Go, etc.) and encodes language-specific semantics into a unified OWL2 ontology. It adopts two complementary modules. First, a transitive-closure engine fetches all structurally linked symbols via single SPARQL property-path queries, capturing multi-hop relations missed by string matching. Second, the OWL Software Knowledge Map (OWL-SKM) precomputes a compact 3KB summary with module trees, core APIs and issue-related symbols, directing agents to target modules in the first query. Evaluated on 18 SWE-bench Pro instances, OwlPath obtains a 68.4% strict-apply rate versus 66.7% for the CodeGraph baseline, cutting token usage by 28.8% and runtime by 39.5%. In offline retrieval tests over 67 instances, OwlPath improves recall 2.06 times (0.464 vs 0.226) and reaches 88.1% hit rate compared to CodeGraph's 59.7%. On a 37-question structural retrieval benchmark, recall rises from 4.4% to 28.8%, with 69-80% accuracy on transitive caller and interface tasks.
The increasing complexity of modern software systems has made automated code generation a fundamental task in software engineering. However, existing approaches often fail to adequately capture the intricate, multi-level dependencies among code entities, leading to generated code that is logically incomplete or difficult to integrate into real-world systems. To address this limitation, we propose a dependency-aware code generation framework that explicitly models interactions among code entities through a graph-based representation. We decompose dependencies into two complementary components: a quantized matrix that captures strong, explicit relations, and a sparse low-rank factorization that models weaker, implicit interactions. The decomposition is efficiently learned via an alternating optimization procedure. During code generation, the learned dependency structure is incorporated as a constraint, ensuring both semantic coherence and structural consistency of the generated code. Furthermore, we introduce a sparse triplet representation for strong dependencies, significantly improving storage efficiency and computational scalability. Extensive experiments demonstrate that our approach consistently produces code with superior semantic alignment and structural fidelity compared to existing methods.
Mingqiao Mo, Yangcheng Zeng, Zikai Xiao et al.· 0 citations