Build-Aware Incremental C-to-Rust Migration via Skeleton-First Translation and Historical Knowledge Reuse

TL;DR

This paper introduces His2Trans, a build-aware framework for incremental C-to-Rust migration that reconstructs project skeletons and leverages historical knowledge to improve build success and reduce unsafe code.

Contribution

It presents a novel approach combining build trace reconstruction and knowledge reuse to enable stable, project-level C-to-Rust migration in complex build environments.

Findings

Achieves 97.51% incremental compilation pass rate on OpenHarmony modules.

Reduces unsafe code ratio by 24.02 percentage points compared to C2Rust.

Decreases average repair rounds on unseen modules by about 60%.

Abstract

Automating C-to-Rust migration for industrial software remains difficult because build-critical context is scattered across compile configurations, macros, external symbols, and cross-module dependencies, while reusable migration knowledge is often buried in prior C/Rust evolution. As a result, existing LLM-based approaches often work well on isolated functions or small benchmarks but struggle to produce stable project-level translations in partially migrated systems. We present His2Trans, a framework for incremental C-to-Rust migration in build-complex ecosystems where C and Rust coexist. His2Trans first reconstructs a compilable project-level Rust skeleton from build traces, recovering modules, type definitions, signatures, globals, and dependency relations before function-body generation. It then retrieves Rust-side interfaces and local coding patterns mined from historical compilation-accepted C/Rust pairs to guide translation and compiler-feedback repair. We evaluate His2Trans on five OpenHarmony submodules and nine general-purpose C benchmarks. On the OpenHarmony modules, His2Trans achieves a 97.51% incremental compilation pass rate and substantially improves build feasibility over reproduced baselines; the resulting artifacts also support mixed C/Rust builds without observed interface mismatches. On general-purpose benchmarks, it maintains high compilation feasibility, reduces the unsafe ratio by 24.02 percentage points relative to C2Rust, and, with Claude-Opus-4.5, lowers warning counts on compiled outputs. In addition, the self-evolving knowledge base reduces average repair rounds on unseen modules by approximately 60%. These results suggest that combining build-aware skeleton construction with historical knowledge reuse is an effective strategy for practical, gradual C-to-Rust migration.