llvm-project

5ef593b7 - [clangd] [C++ Modules] Enable content validation for module input files (#187653)

[clangd] [C++ Modules] Enable content validation for module input files (#187653) The IsModuleFileUpToDate function was not properly validating input files for C++20 modules. By default, ASTReader skips input file validation for StandardCXXModule files unless ForceCheckCXX20ModulesInputFiles and ValidateASTInputFilesContent are both set. This change: - Passes ValidateASTInputFilesContent=true to ASTReader constructor - Uses ARR_OutOfDate flag for cleaner error handling - Simplifies the validation logic (ReadAST already validates internally) - Adds a test to verify header changes in module units are detected Assised with AI.