https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61333
--- Comment #14 from Jack Howarth <howarth.at.gcc at gmail dot com> --- Without optimization flags on a 24-core x86_64 Fedora 15 box, the timings for one, two and four OMP processes are… clang-3.4.0 (clang-omp/openmp) 69.988439 sec: 34.962212 sec: 17.641935 sec gcc 4.6.3 81.324524 sec: 40.878640 sec: 20.741782 sec gcc 4.8 branch svn 80.953598 sec: 40.650732 sec: 20.635248 sec at -O1 clang-3.4.0 (clang-omp/openmp) 16.187348 sec: 8.189783 sec: 4.293277 sec gcc 4.6.3 32.315830 sec: 16.233432 sec: 8.257077 sec gcc 4.8 branch svn 32.292952 sec: 16.270113 sec: 8.258137 sec at -O2 clang-3.4.0 (clang-omp/openmp) 13.463402 sec: 6.690053 sec: 3.570961 sec gcc 4.6.3 15.671699 sec: 7.895216 sec: 4.133647 sec gcc 4.8 branch svn 15.639710 sec: 7.878182 sec: 4.120302 sec at -O3 clang-3.4.0 (clang-omp/openmp) 13.260507 sec: 6.698891 sec: 3.559403 sec gcc 4.6.3 15.947264 sec: 7.991567 sec: 4.158251 sec gcc 4.8 branch svn 15.607232 sec: 7.861177 sec: 4.150581 sec at -Os clang-3.4.0 (clang-omp/openmp) 16.266355 sec: 8.229083 sec: 4.236148 sec gcc 4.6.3 16.921628 sec: 8.539645 sec: 4.447783 sec gcc 4.8 branch svn 15.914723 sec: 8.658947 sec: 4.719782 sec at -Ofast clang-3.4.0 (clang-omp/openmp) 10.822510 sec: 5.500982 sec: 3.484604 sec gcc 4.6.3 13.752500 sec: 6.764537 sec: 3.601730 sec gcc 4.8 branch svn 13.224638 sec: 6.658421 sec: 3.556949 sec
