C++ g++ versus C gcc fastest performance Always look at the source code. If the fastest programs are hand-written vector instructions, does the host language matter? You might be more interested in the less optimised programs — more seconds, less gz source code. fannkuch-redux source secs mem gz cpu secs C gcc #6 2.16 19,516 1582 8.53 C++ g++ #6 3.25 19,788 1535 12.89 C++ g++ #7 13.93 19,660 1156 13.93 C gcc #4 14.20 19,516 1190 14.20 C gcc #5 6.91 19,644 917 27.13 C++ g++ #5 7.97 19,788 987 31.14 C++ g++ #3 36.80 19,660 600 36.80 C++ g++ #4 9.47 19,660 1445 37.11 C++ g++ #2 9.82 19,656 1446 38.58 C gcc #3 39.57 19,516 574 39.57 C++ g++ 10.59 19,660 1065 41.61 C gcc 42.24 19,640 514 42.24 C gcc #2 11.16 19,644 1563 43.66 n-body source secs mem gz cpu secs C gcc #9 2.10 19,520 1639 2.10 C++ g++ #0 2.14 19,676 1933 2.14 C gcc #8 3.70 19,520 1398 3.69 C++ g++ #7 3.97 19,804 1815 3.97 C++ g++ #2 4.20 19,676 1884 4.19 C gcc #4 4.30 19,520 1496 4.30 C gcc #6 4.96 19,520 1186 4.96 C gcc 5.18 19,520 1179 5.18 C gcc #2 5.18 19,520 1270 5.18 C gcc #3 5.24 19,520 1214 5.24 C++ g++ #3 5.30 19,804 1402 5.30 C gcc #5 5.41 19,648 1436 5.41 C++ g++ #9 5.43 19,676 1536 5.43 C++ g++ #4 5.44 19,804 1434 5.44 C++ g++ #5 6.01 19,676 1544 6.00 C++ g++ 6.49 19,676 1666 6.49 C++ g++ #8 6.57 19,676 1524 6.57 C gcc #7 6.81 19,520 1250 6.81 C++ g++ #6 6.89 19,676 1674 6.89 spectral-norm source secs mem gz cpu secs C gcc #6 0.41 19,760 1203 1.61 C gcc #5 0.72 19,520 576 2.84 C++ g++ #6 0.72 19,812 1050 2.84 C gcc #7 0.73 19,520 906 2.84 C gcc #4 0.72 19,520 1145 2.84 C++ g++ #5 1.32 19,684 1050 5.25 C++ g++ 5.36 19,684 459 5.36 C gcc 5.39 19,520 390 5.39 C gcc #3 1.43 19,520 470 5.68 C++ g++ #8 1.52 19,684 1284 6.04 C gcc #8 Make Error mandelbrot source secs mem gz cpu secs C++ g++ 0.89 34,944 1797 3.46 C++ g++ #4 0.89 35,200 3554 3.47 C++ g++ #6 0.98 35,072 1014 3.89 C gcc #6 1.28 33,280 1141 5.11 C gcc #8 1.63 33,536 788 6.30 C++ g++ #0 2.35 35,328 2752 9.28 C++ g++ #8 4.79 35,072 749 13.12 C++ g++ #5 13.33 34,688 596 13.33 C++ g++ #9 3.50 35,200 732 13.49 C gcc #4 3.48 33,152 805 13.85 C gcc 3.49 32,896 828 13.88 C gcc #7 3.49 33,152 1000 13.89 C++ g++ #7 3.49 35,072 1023 13.90 C gcc #3 3.54 32,768 769 14.07 C gcc #9 4.22 33,280 700 16.30 C++ g++ #2 16.90 34,560 700 16.90 C gcc #2 24.97 19,520 412 24.97 C++ g++ #3 27.26 19,804 421 27.25 pidigits source secs mem gz cpu secs C gcc #2 0.81 19,520 422 0.81 C++ g++ #5 0.86 19,804 804 0.86 C++ g++ #4 0.88 19,804 521 0.88 C gcc 0.88 19,520 459 0.88 regex-redux source secs mem gz cpu secs C gcc #5 0.80 152,388 1403 2.03 C++ g++ #6 1.15 276,276 2856 2.18 C gcc #2 3.23 103,296 1121 3.23 C gcc #4 0.96 152,256 1237 3.27 C gcc #3 1.72 103,680 1273 3.29 C++ g++ #2 2.84 212,776 706 3.60 C++ g++ 3.62 212,180 662 3.62 C++ g++ #5 3.86 215,556 859 4.54 C++ g++ #3 12.41 217,580 859 17.91 C++ g++ #4 Make Error fasta source secs mem gz cpu secs C gcc #9 0.78 19,520 1469 0.78 C gcc #5 1.24 19,520 1286 1.24 C++ g++ #8 0.76 19,792 2758 1.51 C++ g++ #2 1.81 19,668 1129 1.81 C++ g++ 1.90 19,664 1064 1.90 C++ g++ #3 2.62 19,664 1311 2.62 C gcc #6 0.93 19,648 1936 2.73 C gcc #8 2.79 19,520 1299 2.79 C gcc #4 3.02 19,520 1244 3.02 C gcc #2 0.83 19,520 2270 3.26 C gcc #7 0.85 19,648 2018 3.29 C++ g++ #4 3.32 19,664 1291 3.32 C gcc 3.74 19,520 1209 3.73 C++ g++ #6 1.05 19,668 2326 3.85 C++ g++ #5 1.05 19,668 2345 3.88 C gcc #3 4.49 19,520 825 4.48 C++ g++ #7 Make Error k-nucleotide source secs mem gz cpu secs C++ g++ #2 1.97 156,504 1634 5.87 C gcc 3.80 130,432 1512 12.64 C++ g++ #3 4.19 165,592 1280 13.77 C++ g++ 6.90 757,080 1452 14.68 reverse-complement source secs mem gz cpu secs C gcc #7 0.43 499,872 1899 0.58 C++ g++ #2 0.70 499,840 2099 0.70 C gcc #8 0.50 499,872 1551 0.86 C gcc #6 0.96 703,064 828 1.37 C gcc #5 1.50 994,176 654 1.50 C gcc #2 1.05 994,432 757 1.55 C gcc #4 3.66 500,480 716 3.66 C++ g++ #6 3.20 1,517,660 1827 4.22 C++ g++ 6.56 980,060 599 6.56 C++ g++ #5 35.10 771,556 704 35.10 C++ g++ #3 Bad Output binary-trees source secs mem gz cpu secs C++ g++ #7 0.95 201,400 896 3.30 C++ g++ #5 1.14 200,660 891 3.98 C gcc #2 1.51 169,088 816 4.17 C++ g++ #9 1.72 135,936 815 4.46 C++ g++ #6 1.88 266,112 851 4.47 C gcc #3 1.89 134,400 842 4.59 C++ g++ #3 1.88 265,600 951 4.72 C++ g++ #8 2.18 265,984 826 5.11 C++ g++ 2.65 2,040,792 760 9.07 C gcc 20.83 264,192 660 20.83 C++ g++ #2 21.51 265,856 514 21.51 C gcc #5 8.27 351,232 914 30.31 C++ g++ #4 Make Error C++ g++ Ubuntu 13.2.0-4ubuntu3 C gcc 13.2.0-4ubuntu3 all C++ g++ programs & measurements all C gcc programs & measurements