LLVM Clang 3.5 Brings Some Compiler Performance Improvements

OpenMP support sadly didn't make it into the LLVM Clang 3.5 release, a long awaited feature for many users.

While OpenMP is left behind, some GraphicsMagick tests were reporting performance improvements out of this six-month update to the liberally licensed compiler.

The Himeno performance might have regressed a little bit with LLVM Clang 3.5.