The company Ceemple just released their C++ compiler under Open Source license.

Zapcc compiler open source now available

by Ceemple

About the compiler:

Zapcc is a newer C++ compiler that goes for

• Faster Builds: Significant compilation speedups for heavy templated C++ headers such as ScyllaDB, Webkit, LLVM
• Clang/LLVM Based: Zapcc is based on clang and frequently updated from the latest svn
• Full Linux Support: Zapcc currently supports Linux x64, Windows x64 support with mingw-w64 is experimental 
• Drop-in Replacement: Zapcc is a drop-in replacement for clang and gcc, and supports all build system