Worked on the microsoft/DirectXShaderCompiler repository to address a build failure affecting modern libc++ toolchains. Focused on a targeted compatibility patch within StringRef.h, the solution disabled specific std::is_nothrow_constructible specializations when compiling under libc++, ensuring that existing workarounds and runtime behavior for non-libc++ environments remained intact. The fix was implemented entirely at compile time, avoiding any changes to runtime code generation or ABI. Using C++ and leveraging expertise in compiler design and cross-platform development, the work restored build stability on Apple toolchains such as Xcode 26.4 and Apple clang 21, while maintaining clear documentation and traceability.