The Computer Language
24.11 Benchmarks Game

C gcc versus C clang fastest performance

How the programs are written matters! 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 2.14 19,704 1582 8.43
* C clang #6 2.24 19,772 1582 8.86
* C clang #4 13.37 19,772 1190 13.37
* C gcc #4 14.04 19,704 1190 14.03
C gcc #5 7.29 19,704 917 28.25
C clang #5 8.09 19,772 917 31.94
* C clang #2 8.67 19,772 1563 34.02
C clang #3 34.16 19,772 574 34.15
C clang #8 36.39 19,492 483 36.38
C clang 36.51 19,772 514 36.50
C gcc #3 36.80 19,704 574 36.79
C gcc #8 39.33 19,492 483 39.32
C gcc 39.61 19,704 514 39.60
* C gcc #2 10.19 19,704 1563 39.99
n-body
source secs mem gz cpu secs
* C gcc #9 2.10 19,772 1639 2.10
* C clang #9 2.20 19,772 1639 2.20
* C gcc #4 4.05 19,772 1398 4.05
* C clang #5 4.86 19,772 1436 4.86
C gcc #6 4.97 19,772 1186 4.97
C clang #6 5.16 19,772 1186 5.16
C gcc #2 5.19 19,772 1270 5.19
C gcc #3 5.23 19,772 1214 5.23
C gcc 5.23 19,772 1179 5.23
C clang 5.37 19,772 1179 5.37
C clang #2 5.42 19,772 1270 5.42
* C gcc #5 5.43 19,772 1436 5.43
C gcc #8 5.54 19,492 1193 5.54
* C clang #4 5.60 19,772 1398 5.59
C clang #8 5.72 19,492 1193 5.72
C clang #3 6.12 19,772 1214 6.12
C clang #7 6.77 19,772 1250 6.77
C gcc #7 6.89 19,772 1250 6.88
spectral-norm
source secs mem gz cpu secs
* C clang #6 0.38 19,772 1203 1.52
* C gcc #6 0.40 19,772 1203 1.59
* C gcc #5 0.72 19,772 576 2.85
* C gcc #7 0.72 19,772 906 2.85
* C gcc #4 0.72 19,772 1145 2.85
* C clang #4 0.72 19,772 1145 2.86
* C clang #2 0.72 19,772 941 2.87
* C clang #5 0.72 19,772 576 2.88
C gcc #8 5.40 19,772 389 5.39
C clang #8 5.40 19,772 389 5.40
C gcc #3 1.43 19,772 470 5.70
C clang #3 1.46 19,772 470 5.77
* C clang #7 1.82 19,772 906 7.24
* C gcc #2   Make Error  
mandelbrot
source secs mem gz cpu secs
C clang #9 1.22 34,332 700 4.85
* C gcc #6 1.28 33,400 1147 5.10
C clang #5 1.53 34,864 788 6.09
C gcc #5 1.63 33,512 788 6.31
* C clang #4 3.47 34,328 805 13.82
* C gcc #4 3.52 33,060 805 13.89
* C gcc 3.49 32,864 828 13.92
* C clang 3.49 33,172 828 13.93
* C gcc #7 3.51 33,276 1000 13.95
* C clang #7 3.53 34,216 1000 14.00
* C gcc #3 3.53 32,860 769 14.09
* C clang #3 3.55 33,108 769 14.15
C gcc #9 4.07 33,128 700 15.70
C gcc #8 25.15 19,496 412 25.15
C clang #8 25.27 19,496 412 25.27
* C clang #6   Make Error  
fasta
source secs mem gz cpu secs
C gcc #9 0.78 19,772 1469 0.78
C clang #9 0.78 19,772 1469 0.78
C clang #5 1.19 19,772 1286 1.19
C gcc #5 1.24 19,772 1286 1.24
C clang #7 2.43 19,772 1299 2.43
C gcc #7 2.76 19,772 1299 2.76
C gcc #6 0.94 19,772 1936 2.78
C clang #6 1.03 19,772 1936 3.03
C gcc #2 0.82 19,772 2276 3.24
C clang #2 0.83 19,772 2276 3.28
C clang 3.46 19,772 1213 3.46
C gcc 3.70 19,772 1213 3.70
C clang #8 4.60 19,772 825 4.60
C gcc #8 4.62 19,772 825 4.62
C gcc #4   Make Error  
C clang #4   Make Error  
k-nucleotide
source secs mem gz cpu secs
C gcc 3.84 130,408 1512 12.45
C clang 6.30 129,228 1512 13.92
reverse-complement
source secs mem gz cpu secs
* C gcc #7 0.44 499,992 1899 0.59
* C clang #7 0.45 499,996 1899 0.63
C clang #9 0.46 499,976 1551 0.70
C gcc #9 0.48 500,032 1551 0.76
C gcc #6 0.96 675,260 828 1.36
C gcc #5 1.53 994,108 654 1.53
C gcc #2 1.06 994,536 757 1.58
C clang #2 1.16 994,536 757 1.69
C clang #5 2.08 994,108 654 2.07
* C gcc #4 3.70 500,452 716 3.69
* C clang #4 3.74 500,452 716 3.74
C clang #6 1.03 703,416 828 4.07
binary-trees
source secs mem gz cpu secs
C gcc #2 1.53 169,284 816 4.18
C gcc #3 1.96 134,540 842 4.70
C clang #2 1.66 170,236 816 5.36
C clang #3 1.89 134,272 842 5.88
C clang 17.79 264,064 660 17.79
C clang #8 19.63 285,536 607 19.62
C gcc #8 21.08 285,544 607 21.08
C gcc 21.67 264,244 660 21.67
C gcc #5 8.77 351,332 914 31.93
C clang #5 9.25 351,328 914 33.65
pidigits
source secs mem gz cpu secs
C clang #2 0.74 19,772 422 0.74
C gcc #2 0.74 19,772 422 0.74
C gcc 0.74 19,772 459 0.74
C clang 0.74 19,772 459 0.74
regex-redux
source secs mem gz cpu secs
C gcc #5 0.81 152,500 1403 2.03
C clang #5 0.82 154,568 1403 2.82
C gcc #2 3.21 103,288 1121 3.21
C clang #2 3.22 103,364 1121 3.22
C gcc #4 0.97 152,264 1237 3.28
C gcc #3 1.72 103,736 1273 3.31
C clang #4 0.98 154,488 1237 3.82
C clang #3 1.75 105,848 1273 4.31
C gcc

gcc (Ubuntu 14.2.0-4ubuntu2) 14.2.0

C clang

Ubuntu clang version 18.1.8 (11)