Low-Level Virtual Machine (LLVM), C language family frontend

 The Low-Level Virtual Machine (LLVM) is a collection of libraries and
 tools that make it easy to build compilers, optimizers, Just-In-Time
 code generators, and many other compiler-related programs. LLVM
 uses a single, language-independent virtual instruction set both
 as an offline code representation (to communicate code between
 compiler phases and to run-time systems) and as the compiler internal
 representation (to analyze and transform programs). This persistent
 code representation allows a common set of sophisticated compiler
 techniques to be applied at compile-time, link-time, install-time,
 run-time, or "idle-time" (between program runs).
 .
 Clang project is a C, C++, Objective C and Objective C++ front-end
 for the LLVM compiler. Some of its goals 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 'BSD' 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