December 2025 monthly summary for swift-driver: Reverted optimization record path handling to restore stable output and simplify the compilation path. Removed logic for optimization records in primary file compilation mode, including related checks and flags, resulting in more predictable SIL and LLVM IR outputs. The change reduces edge-case risk and improves maintainability, enabling smoother downstream integrations and CI reliability.

Month: 2025-09 — Focused on improving size reporting accuracy for Mach-O binaries in the llvm-size tool and expanding test coverage. Key outcomes include a fix to the --totals aggregation for Mach-O files by correctly handling Darwin segment sizes and introducing categories such as __OBJC, plus updates to tests with Mach-O specific cases. The change reduces incorrect total size calculations and improves reliability for developers monitoring app sizes on Apple platforms.

December 2024: Focused on strengthening cross-language build stability for swift-package-manager. Delivered a precise header guard to prevent Foundation.h inclusion in non-Objective-C/C++ sources, addressing miscompilations in mixed-language projects. Implemented via gating resource access headers with __OBJC__, aligned with issue #7962. The changes were implemented in two commits to ensure robust coverage across clang-based builds. Impact includes reduced build-time failures, smoother multi-language integration, and clearer build logs in mixed-language scenarios. Technologies leveraged: preprocessor guards, __OBJC__ macro, cross-language build analysis, and repository hygiene to minimize unintended Foundation.h exposure.