C gcc versus C++ g++ fastest programs Always look at the source code. These are only the fastest programs. Do some of them use manually vectorized SIMD? Look at the other programs. They may seem more-like a fair comparison to you. regex-redux source secs mem gz busy cpu load C gcc 0.80 152,196 1397 2.03 48% 100% 54% 53% C++ g++ 1.08 203,816 1315 3.38 78% 99% 65% 73% fasta source secs mem gz busy cpu load C gcc 0.78 1,220 1463 0.79 1% 0% 0% 100% C++ g++ 0.78 2,468 2751 1.62 8% 99% 99% 3% spectral-norm source secs mem gz busy cpu load C gcc 0.72 1,100 569 2.86 100% 99% 100% 100% C++ g++ 0.72 1,216 1044 2.86 100% 100% 99% 100% n-body source secs mem gz busy cpu load C gcc 4.30 8 1391 4.32 0% 0% 0% 100% C++ g++ 4.09 1,800 1808 4.13 100% 0% 0% 0% pidigits source secs mem gz busy cpu load C gcc 0.73 2,848 416 0.75 1% 100% 1% 0% C++ g++ 0.60 4,944 986 2.38 100% 100% 98% 100% reverse-complement source secs mem gz busy cpu load C gcc 0.86 698,264 820 1.27 1% 18% 100% 28% C++ g++ 0.63 499,704 2093 0.64 0% 100% 2% 0% mandelbrot source secs mem gz busy cpu load C gcc 1.27 31,692 1135 5.08 100% 100% 100% 99% C++ g++ 0.84 34,604 3542 3.28 98% 99% 98% 95% fannkuch-redux source secs mem gz busy cpu load C gcc 7.52 836 910 29.37 99% 100% 93% 99% C++ g++ 4.91 1,912 1482 19.45 100% 99% 97% 100% binary-trees source secs mem gz busy cpu load C gcc 1.79 168,760 809 5.35 64% 64% 71% 100% C++ g++ 1.04 154,824 1122 3.74 88% 100% 88% 86% k-nucleotide source secs mem gz busy cpu load C gcc 3.81 130,112 1506 12.18 54% 87% 79% 100% C++ g++ 1.95 156,372 1631 5.95 73% 70% 92% 70% C gcc gcc (Ubuntu 10.2.0-13ubuntu1) 10.2.0 C++ g++ g++ (Ubuntu 10.2.0-13ubuntu1) 10.2.0 all C gcc programs & measurements all C++ g++ programs & measurements