GCC 5.2 Compiler Benchmarks With ARM Cortex-A57 A Mixed Bag

First up, with the Fortran-based NAS Parallel Benchmarks, the results are rather concerning for GCC 5. NPB is a very demanding test and with GCC 5.2.1 it's quite clear the performance is measurably lower than on GCC 4.x while the hardware and compiler flags were maintained the same.

Let's see what happens in other tests...

In some other tests like Dolfyn and FFTE, there wasn't much change in performance from GCC 4.8 to GCC 5.2 on these Cortex-A57 cores.

With FFTW is the first win for the newer GNU Compiler Collections where there is a significant performance improvement.