Free Pascal 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 gcc #4 14.20 19,516 1190 14.20 C gcc #5 6.91 19,644 917 27.13 C gcc #3 39.57 19,516 574 39.57 Free Pascal 10.58 19,664 1032 42.13 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 gcc #8 3.70 19,520 1398 3.69 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 gcc #5 5.41 19,648 1436 5.41 Free Pascal 6.28 19,680 1315 6.28 Free Pascal #2 6.28 19,680 1328 6.28 C gcc #7 6.81 19,520 1250 6.81 Free Pascal #3 7.16 19,680 1424 7.16 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 gcc #7 0.73 19,520 906 2.84 C gcc #4 0.72 19,520 1145 2.84 C gcc 5.39 19,520 390 5.39 C gcc #3 1.43 19,520 470 5.68 Free Pascal #3 1.44 19,824 632 5.70 Free Pascal #2 1.45 19,696 548 5.71 Free Pascal 11.77 19,696 429 11.77 C gcc #8 Make Error mandelbrot source secs mem gz cpu secs C gcc #6 1.28 33,280 1141 5.11 C gcc #8 1.63 33,536 788 6.30 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 gcc #3 3.54 32,768 769 14.07 Free Pascal #8 3.90 33,024 958 15.47 C gcc #9 4.22 33,280 700 16.30 C gcc #2 24.97 19,520 412 24.97 Free Pascal #7 6.55 36,992 930 26.05 Free Pascal #3 26.52 19,680 533 26.52 Free Pascal #2 10.96 33,024 833 29.39 Free Pascal 10.98 33,024 833 29.41 Free Pascal #6 7.45 36,096 788 29.64 pidigits source secs mem gz cpu secs C gcc #2 0.81 19,520 422 0.81 Free Pascal #3 0.87 19,824 493 0.87 C gcc 0.88 19,520 459 0.88 Free Pascal #2 5.36 19,696 802 5.36 Free Pascal 14.63 19,696 3054 14.63 regex-redux source secs mem gz cpu secs C gcc #5 0.80 152,388 1403 2.03 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 Free Pascal 5.51 103,016 1300 5.51 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 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 gcc 3.74 19,520 1209 3.73 C gcc #3 4.49 19,520 825 4.48 Free Pascal #6 5.58 19,676 1196 5.58 Free Pascal #5 5.64 19,792 1225 5.64 k-nucleotide source secs mem gz cpu secs C gcc 3.80 130,432 1512 12.64 reverse-complement source secs mem gz cpu secs C gcc #7 0.43 499,872 1899 0.58 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 Free Pascal #2 3.77 525,048 773 3.77 binary-trees source secs mem gz cpu secs C gcc #2 1.51 169,088 816 4.17 C gcc #3 1.89 134,400 842 4.59 Free Pascal #5 2.09 132,608 929 4.98 Free Pascal #6 2.09 132,608 939 4.99 Free Pascal #7 2.12 132,608 975 5.07 C gcc 20.83 264,192 660 20.83 C gcc #5 8.27 351,232 914 30.31 Free Pascal Free Pascal Compiler version 3.2.2 [2021/05/16] C gcc 13.2.0-4ubuntu3 all Free Pascal programs & measurements all C gcc programs & measurements