Worked on the swiftlang/llvm-project repository to enhance build reliability by addressing a C++17 compilation error under MSVC 2022. Focused on stabilizing the build system, the work involved updating BitstreamRemarkParser.h to add explicit template arguments to friend declarations, ensuring compatibility with modern C++ standards. This change improved cross-compiler support and reduced the risk of future regressions. Emphasized code quality and maintainability by documenting the update and aligning with project guidelines. Utilized C++ and build system expertise to resolve compiler errors, contributing to a more robust development environment without introducing new user-facing features during the period.