LLVM has found its way into many projects from Mono to Gallium3D to in use by, well, just a code compiler. The latest usage of LLVM comes in the form of SMACK, a C/C++ static checker.
SMACK statically checks properties of programs and handles checking user-provided assertions. The tool is open-source and powered by LLVM.
With the code being lowered down into LLVM bit-code, in theory any LLVM-supported language could be used for this static checker but the specific focus is around C and C++ languages.
For more details on SMACK, visit its GitHub page.