$ gcc -O2 -std=c99 -lm -o c c.c $ time ./c ./c 2.49s user 0.07s system 99% cpu 2.567 total $ nim -d:release c nim $ time ./nim ./nim 2.47s user 0.07

$ gcc -O2 -std=c99 -lm -o c c.c $ time ./c ./c 2.49s user 0.07s system 99% cpu 2.567 total $ nim -d:release c nim $ time ./nim ./nim 2.47s user 0.07s system 99% cpu 2.538 total Yes, --opt:speed is slower indeed: $ nim --opt:speed c nim $ time ./nim ./nim 3.02s user 0.07s system 99% cpu 3.095 total