A Quick Look At GCC 4.9 vs. LLVM Clang 3.5

Unfortunately for many common open-source benchmarks, the LLVM Clang performance is still lagging behind since the upstream compiler still lacks support for OpenMP... Developers have been working on OpenMP support but it's not yet all within their mainline code. As a result, for tests using OpenMP for extracting multi-core performance, Clang is lagging behind GCC. With GCC 4.9 there is now OpenMP 4.0 support.

With the Himeno Poisson Pressure Solver benchmark, the LLVM Clang 3.5 SVN compiler is running ahead of GCC 4.8.2 stable and GCC 4.9 in its release candidate form.

As expected, with all tests of timing the compilation of a given real-world open-source application, LLVM's Clang compiler wins. LLVM/Clang is widely known to give the fastest compile times over GCC while consuming a lower amount of system memory as well.