arXiv subjects

Jiangchang Wu

Publications and source records attributed to Jiangchang Wu.

3 recordsLinked to original sources

arXiv2026

ClozeMaster: Fuzzing Rust Compiler by Harnessing LLMs for Infilling Masked Real Programs

Ensuring the reliability of the Rust compiler is of paramount importance, given increasing adoption of Rust for critical systems development, due to its emphasis on memory and thread safety. However, generating valid test programs for the Rust compiler poses significant challenges, given Rust's complex syntax and strict requirements. With the growing popularity of large language models (LLMs), much research in software testing has explored using LLMs to generate test cases. Still, directly using LLMs to generate Rust programs often results in a large number of invalid test cases. Existing studies have indicated that test cases triggering historical compiler bugs can assist in software testing. Our investigation into Rust compiler bug issues supports this observation. Inspired by existing work and our empirical research, we introduce a bracket-based masking and filling strategy called clozeMask. The clozeMask strategy involves extracting test code from historical issue reports, identifying and masking code snippets with specific structures, and using an LLM to fill in the masked portions for synthesizing new test programs. This approach harnesses the generative capabilities of LLMs while retaining the ability to trigger Rust compiler bugs. It enables comprehensive testing of the compiler's behavior, particularly exploring edge cases. We implemented our approach as a prototype CLOZEMASTER. CLOZEMASTER has identified 27 confirmed bugs for rustc and mrustc, of which 10 have been fixed by developers. Furthermore, our experimental results indicate that CLOZEMASTER outperforms existing fuzzers in terms of code coverage and effectiveness.

cs.SE↗

arXiv2025

Isolating Compiler Faults via Multiple Pairs of Adversarial Compilation Configurations

Compilers are fundamental to modern software development, making the effective identification and resolution of compiler faults essential. However, localizing these faults to specific source files remains highly challenging due to the complexity and scale of modern compiler infrastructures. In this study, we propose MultiConf, a novel approach that automatically isolates compiler faults by constructing multiple pairs of adversarial compilation configurations. Each adversarial compilation configuration pair consists of a failing configuration and its corresponding passing configuration, which differ in only a small number of fine-grained options. MultiConf generates failing configurations through a lightweight construction process and derives the corresponding passing configurations by selectively disabling bug-related fine-grained options. We then employ a Spectrum-Based Fault Localization (SBFL) formula to rank the suspiciousness of compiler source files. Each adversarial configuration pair independently produces a ranking, which is subsequently aggregated using a weighted voting scheme to derive a final suspiciousness ranking, enabling more accurate and robust fault localization. We evaluate MultiConf on a benchmark of 60 real-world GCC compiler bugs. The results demonstrate that MultiConf significantly outperforms existing compiler fault localization techniques in both effectiveness and efficiency. In particular, MultiConf successfully localizes 27 out of 60 bugs at the Top-1 file level, representing improvements of 35.0% and 28.6% over the two state-of-the-art approaches, Odfl(20) and Basic(21), respectively.

cs.SE↗

arXiv2025

Using a Sledgehammer to Crack a Nut? Revisiting Automated Compiler Fault Isolation

Background: Compilers are fundamental to software development, translating high-level source code into executable software systems. Faults in compilers can have severe consequences and thus effective localization and resolution of compiler bugs are crucial. Problem: In practice, developers often examine version history to identify and investigate bug-inducing commit (BIC) for fixing bugs. However, while numerous sophisticated Spectrum-Based Fault Localization (SBFL) techniques have been proposed for compiler fault isolation, their effectiveness has not been evaluated against the BIC-based strategies widely adopted in practice. Objective: This study aims to bridge this gap by directly comparing a BIC-based strategy, Basic, with representative SBFL techniques in the context of compiler fault localization. The BIC-based strategy closely aligns with common developer practices, as it directly identifies the BIC and treats the files modified in that commit as faulty candidates. Method: The Basic identifies the most recent good release and earliest bad release, and then employs a binary search to pinpoint the bug-inducing commit. All files modified in the identified commit are flagged as potentially faulty. We rigorously compare Basic against SBFL-based techniques using a benchmark consisting of 60 GCC bugs and 60 LLVM bugs. Result: Our analysis reveals that Basic performs comparably to, and in many cases outperforms, state-of-the-art SBFL-based techniques, particularly on the critical Top-1 and Top-5 ranking metrics. Conclusion: This study provides new insights into the practical effectiveness of SBFL-based techniques in real-world compiler debugging scenarios. We recommend that future research adopt Basic as a baseline when developing and evaluating new compiler fault isolation methods.

cs.SE↗