C++ Modules are a highly anticipated feature in the C++ programming language that aims to improve build times and reduce the complexity of managing large codebases. Modules allow for more efficient compilation by separating interface and implementation code, enabling faster recompilations, and avoiding unnecessary header file parsing.

In this blog post, we will explore the current status of C++ Modules implementation in three popular compilers: GCC, Clang, and MSVC.

1. GCC

GCC (GNU Compiler Collection) is one of the most widely used compilers in the C++ community. The GCC team has been actively working on introducing C++ Modules support. The implementation is available in experimental mode starting from GCC 10 and requires enabling the -fmodules-ts flag.

While GCC’s support for C++ Modules is still considered experimental, it has made significant progress. It can handle basic use cases and provides features like module interface unit (MIU) files, module partitions, and module import/export declarations. However, some advanced features are yet to be fully supported, such as the usage of preprocessor macros in module interfaces.

2. Clang

Clang, the LLVM-based C++ compiler, has also been actively working on C++ Modules support. Clang’s implementation is quite advanced and more stable compared to GCC’s implementation. Clang has been providing experimental support for C++ Modules since version 9, which can be enabled using the -fmodules-ts flag.

Clang’s implementation covers a broad range of C++ Modules features, including module partitions, module interfaces, and support for preprocessor macros in module interfaces. It also provides better diagnostics when handling module-related errors. Clang’s implementation has been gaining popularity among developers due to its stability and rich feature set.

3. MSVC

MSVC (Microsoft Visual C++) is the C++ compiler provided by Microsoft for Windows development. Unlike GCC and Clang, MSVC’s support for C++ Modules is still under development. As of now, the support is limited and not yet available in the production releases of Visual Studio.

Microsoft has been actively soliciting feedback from the C++ community to shape their C++ Modules implementation. They have released several previews of MSVC with experimental support for C++ Modules, which can be enabled using the /experimental:module flag. However, it is important to note that the MSVC implementation is still in progress and may have limitations compared to GCC and Clang.

Conclusion

C++ Modules are an exciting addition to the C++ programming language, aiming to improve build times and simplify code organization. While GCC and Clang have made notable progress in implementing C++ Modules, with Clang being more stable and feature-rich, MSVC’s support is still under development.

As C++ Modules gain wider adoption and the implementations mature, they have the potential to revolutionize the way we build and manage large C++ projects. Developers are encouraged to explore and experiment with C++ Modules in their respective compilers, keeping in mind the specific limitations and capabilities provided by each implementation.

#C++ #compiler #C++Modules #GCC #Clang #MSVC