Fastest cpu secs Rust versus C clang 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 cpu seconds, less gz source code. fannkuch-redux source mem gz cpu C clang #6 1,152 1576 8.28 C clang #4 1,048 1183 13.24 Rust #6 1,372 1253 14.15 Rust #4 1,372 1020 30.06 Rust #3 1,336 1020 30.07 Rust #5 1,368 1016 30.11 C clang #5 1,052 910 31.60 C clang #3 1,048 567 32.39 C clang #2 1,164 1557 34.16 C clang 1,052 508 37.89 Rust #2 1,232 1191 72.42 n-body source mem gz cpu C clang #9 1,032 1633 2.21 Rust #9 1,052 1874 2.89 Rust #7 1,052 1753 3.24 C clang #8 8 1391 3.49 Rust #6 1,028 1790 4.05 Rust #3 1,108 1540 5.49 C clang #4 1,272 1490 5.59 C clang #5 992 1429 5.62 Rust #2 1,032 1805 5.67 Rust 1,044 1480 5.68 C clang #6 1,280 1180 5.74 Rust #8 1,104 1767 5.78 C clang 1,252 1173 5.96 C clang #2 1,292 1263 6.03 Rust #5 1,104 2220 6.10 Rust #4 1,088 1803 6.25 C clang #3 1,312 1208 6.34 C clang #7 1,292 1244 6.93 spectral-norm source mem gz cpu C clang #6 3,044 1197 1.56 Rust #5 2,560 1055 2.84 Rust #6 2,432 1126 2.84 Rust #7 2,436 932 2.84 Rust #4 2,640 817 2.84 C clang #5 3,332 569 2.86 Rust #2 1,312 1110 2.87 Rust 1,276 1254 2.87 C clang #4 3,184 1139 2.87 Rust #3 1,248 1053 2.98 C clang 1,456 383 5.31 C clang #3 3,368 463 5.72 mandelbrot source mem gz cpu Rust #6 33,872 1332 4.18 C clang #9 30,664 694 5.15 Rust #8 32,624 763 5.48 Rust #7 32,732 757 5.50 Rust #3 12,824 1007 5.52 C clang #8 32,212 782 6.54 Rust 38,672 868 6.87 Rust #5 33,948 719 10.40 C clang #4 33,936 799 13.85 C clang 30,180 822 13.89 C clang #7 34,224 994 13.91 C clang #3 30,100 763 14.18 C clang #2 996 400 25.27 C clang #6 Make Error pidigits source mem gz cpu Rust #4 2,624 799 0.71 C clang #2 2,888 416 0.73 Rust #2 2,924 1306 0.74 Rust 2,928 1420 0.74 C clang 2,644 452 0.74 Rust #3 2,960 1366 0.83 regex-redux source mem gz cpu Rust #6 153,148 986 1.79 Rust #5 202,556 771 1.83 Rust 152,864 804 1.83 Rust #4 202,612 765 1.87 Rust #3 203,408 719 1.89 Rust #2 152,172 701 1.89 Rust #7 147,360 2458 1.99 C clang #5 154,192 1397 2.80 C clang #2 103,212 1115 3.20 C clang #4 154,168 1230 3.67 C clang #3 105,592 1266 4.35 fasta source mem gz cpu C clang #9 1,256 1463 0.78 C clang #5 1,028 1281 1.21 Rust #7 2,052 2529 1.52 Rust #3 1,104 1233 2.03 C clang #8 1,248 1293 2.48 C clang #6 3,764 1930 2.95 C clang #4 1,032 1240 2.98 Rust #5 2,580 1961 3.10 Rust #2 2,580 1906 3.18 C clang #2 3,952 2268 3.26 C clang #7 3,988 2011 3.28 Rust #8 2,596 1946 3.55 Rust #4 123,860 939 3.57 Rust #6 123,848 955 3.58 C clang 992 1206 3.67 Rust 1,100 1237 4.45 C clang #3 988 819 4.50 k-nucleotide source mem gz cpu Rust #7 131,236 1578 9.12 Rust #8 137,632 1543 10.39 Rust #6 159,088 1691 10.68 Rust #5 133,912 1739 12.23 C clang 129,064 1506 12.44 Rust #2 137,896 1347 16.27 Rust #9 134,732 1841 18.77 Rust #4 136,216 1749 19.31 Rust 152,220 1078 70.04 reverse-complement source mem gz cpu C clang #7 499,220 1965 0.57 C clang #8 499,188 1627 0.65 Rust 499,068 3040 0.76 Rust #2 995,032 1330 1.36 Rust #3 995,032 1097 1.52 C clang #2 994,164 750 1.56 C clang #5 994,092 647 1.96 C clang #4 500,352 709 3.74 C clang #6 723,976 820 3.75 binary-trees source mem gz cpu Rust #5 198,536 765 3.60 Rust #2 200,024 721 4.17 Rust #4 181,444 756 4.40 Rust #3 163,904 754 4.87 C clang #3 133,844 836 5.56 C clang #2 169,564 809 5.81 Rust 132,604 751 7.70 C clang 263,672 654 18.36 C clang #5 351,284 908 32.79 Rust rustc 1.60.0 (7737e0b5c 2022-04-04) LLVM version: 14.0.0 C clang 14.0.0-1ubuntu1 all Rust programs & measurements all C clang programs & measurements