Defects4C: Benchmarking Large Language Model Repair Capability with C/C++ Bugs

Jian Wang, Xiaofei Xie, Qiang Hu, Shangqing Liu, Jiongchi Yu, Jiaolong Kong, and Yi Li

In Proceedings of the 40th IEEE/ACM International Conference on Automated Software Engineering (ASE), 2025

Abstract: Automated Program Repair (APR) plays a critical role in enhancing the quality and reliability of software systems. While substantial progress has been made in Java-based APR, largely facilitated by benchmarks like Defects4J, there remains a significant gap in research on C/C++ program repair, despite the widespread use of C/C++ and the prevalence of associated vulnerabilities. This gap is primarily due to the lack of high-quality, open-source benchmarks tailored for C/C++. To address this issue, we introduce Defects4C, a comprehensive and executable benchmark specifically designed for C/C++ program repair. Our dataset is constructed from real-world C/C++ repositories and includes a large collection of bug-relevant commits (9M in total), 248 high-quality buggy functions, and 102 vulnerable functions, all paired with test cases for reproduction. These resources enable rigorous evaluation of repair techniques and support the retraining of learning-based approaches for enhanced performance. Using Defects4C, we conduct a comprehensive empirical study evaluating the effectiveness of 24 state-of-the-art large language models (LLMs) in repairing C/C++ faults. Our findings offer valuable insights into the strengths and limitations of current LLM-based APR techniques in this domain, highlighting both the need for more robust methods and the critical role of Defects4C in advancing future research.

Cite:

@inproceedings{Wang2025DBL,
  author = {Wang, Jian and Xie, Xiaofei and Hu, Qiang and Liu, Shangqing and Yu, Jiongchi and Kong, Jiaolong and Li, Yi},
  booktitle = {Proceedings of the 40th IEEE/ACM International Conference on Automated Software Engineering (ASE)},
  month = nov,
  title = {{Defects4C}: Benchmarking Large Language Model Repair Capability with {C/C++} Bugs},
  year = {2025}
}