Clang: a C language family frontend for LLVM

The Clang project provides a language front-end and tooling infrastructure for languages in the C language family (C, C++, Objective C/C++, OpenCL, CUDA, and RenderScript) for the LLVM project. Both a GCC-compatible compiler driver (clang) and an MSVC-compatible compiler driver (clang-cl.exe) are provided. You can get and build the source today.

Features and Goals

Some of the goals for the project include the following:

End-User Features:

• Fast compiles and low memory use
• Expressive diagnostics (examples)
• GCC compatibility

Utility and Applications:

• Modular library based architecture
• Support diverse clients (refactoring, static analysis, code generation, etc.)
• Allow tight integration with IDEs
• Use the LLVM 'Apache 2' License

Internal Design and Implementation:

• A real-world, production quality compiler
• A simple and hackable code base
• A single unified parser for C, Objective C, C++, and Objective C++
• Conformance with C/C++/ObjC and their variants

Of course this is only a rough outline of the goals and features of Clang. To get a true sense of what it is all about, see the Features section, which breaks each of these down and explains them in more detail.

Why?

Development of the new front-end was started out of a need for a compiler that allows better diagnostics, better integration with IDEs, a license that is compatible with commercial products, and a nimble compiler that is easy to develop and maintain. All of these were motivations for starting work on a new front-end that could meet these needs.

For a more detailed comparison between Clang and other compilers, please see the Clang comparison page.

Current Status

Clang is considered to be a production quality C, Objective-C, C++ and Objective-C++ compiler when targeting X86-32, X86-64, and ARM (other targets may have caveats, but are usually easy to fix). As example, Clang is used in production to build performance-critical software like Chrome or Firefox.
If you are looking for source analysis or source-to-source transformation tools, Clang is probably a great solution for you. Clang supports C++11, C++14 and C++17, please see the C++ status page for more information.

Get it and get involved!

Start by getting the code, building it, and playing with it. This will show you the sorts of things we can do today and will let you have the "Clang experience" first hand: hopefully it will "resonate" with you. :)

Once you've done that, please consider getting involved in the Clang community. The Clang developers include numerous volunteer contributors with a variety of backgrounds. If you're interested in following the development of Clang, signing up for a mailing list is a good way to learn about how the project works.