Ada 2012 GNAT versus C gcc 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. fannkuch-redux source secs mem gz busy cpu load Ada 2012 GNAT 8.06 4,348 2113 32.11 99% 100% 100% 100% C gcc 7.58 872 910 29.61 100% 98% 99% 93% pidigits source secs mem gz busy cpu load Ada 2012 GNAT 0.88 4,704 1130 0.89 0% 0% 100% 1% C gcc 0.81 2,804 416 0.84 1% 2% 99% 1% k-nucleotide source secs mem gz busy cpu load Ada 2012 GNAT 6.65 258,464 4908 13.94 25% 100% 19% 65% C gcc 3.72 130,260 1506 12.07 100% 89% 78% 57% spectral-norm source secs mem gz busy cpu load Ada 2012 GNAT 0.76 4,260 2770 2.95 97% 97% 96% 97% C gcc 0.40 872 1197 1.58 100% 100% 100% 98% binary-trees source secs mem gz busy cpu load Ada 2012 GNAT 3.12 202,368 2107 9.63 79% 93% 67% 71% C gcc 1.54 168,832 809 4.35 60% 67% 57% 100% n-body source secs mem gz busy cpu load Ada 2012 GNAT 5.13 1,984 2617 5.15 0% 0% 100% 0% C gcc 2.18 768 1633 2.19 0% 100% 0% 0% reverse-complement source secs mem gz busy cpu load Ada 2012 GNAT 2.18 817,648 3283 2.53 0% 40% 76% 0% C gcc 0.86 712,208 820 1.27 99% 28% 1% 19% mandelbrot source secs mem gz busy cpu load Ada 2012 GNAT 4.02 35,812 1819 15.96 100% 99% 99% 100% C gcc 1.27 31,792 1135 5.08 100% 100% 99% 100% fasta source secs mem gz busy cpu load Ada 2012 GNAT 2.60 1,988 2221 2.63 0% 2% 0% 100% C gcc 0.78 1,156 1463 0.78 0% 0% 0% 100% regex-redux source secs mem gz busy cpu load Ada 2012 GNAT 4.33 154,312 3640 12.50 92% 69% 63% 66% C gcc 0.80 152,172 1397 2.01 52% 99% 48% 53% Ada 2012 GNAT GNATMAKE 10.3.0 gcc (Ubuntu 10.3.0-1ubuntu1) 10.3.0 C gcc gcc (Ubuntu 10.3.0-1ubuntu1) 10.3.0 all Ada 2012 GNAT programs & measurements all C gcc programs & measurements