Willus.com's 2011 Win32/64 C Compiler Benchmarks:
First published December 29, 2011, last updated April 8, 2012
Update Apr 8, 2012: Added comments on Open Watcom to the
Update Apr 2, 2012: Corrected Digital Mars version. There is
now a reddit discussion of these benchmarks.
Update Feb 29, 2012: Corrected mistake in intro paragraph and
commented on verification of benchmark results.
Update Jan 21, 2012: Modified MS VC compile flags, added 64-bit MS VC 2010 results, and updated comments on MS VC.
Update Jan 19, 2012: See update pointing to mailing list thread in Summary Section (under Intel's Transcendent Transcendental Performance).
Update Jan 4, 2012: Added Crafty Chess engine benchmark.
Update Jan 3, 2012: Added x264 benchmark.
I published my first compiler performance comparison benchmark nearly a decade ago at the beginning of 2002. Since then, a lot has happened. Intel has come out with their
Core-2 and subsequent CPUs, which now dominate the high-performance computing
world. The GNU folks have been releasing regular, high-quality
updates to gcc, and gcc 4.x, first released in April of 2005, is now fully mainstreamed.
Intel and Microsoft, of course, have continued to evolve their compilers as
well, and there are some interesting newcomers available for testing such as
Fabrice Bellard's Tiny CC. With
all of this progress, I finally started getting the itch to do a thorough
compiler comparison again. Of course, now that I'm most of the way done, I
am reminded why it took me nine years to get motivated for this. It's a lot
of work to get six different compilers to compile over one million lines of C code,
two-thirds of which I did not write myself!
As with my last benchmark, remember that these are only
benchmarks, and as such may not represent the results you will actually
get if you compare these compilers yourself. Plus I am not an expert
on these compilers and had a very finite amount of time to do this, so I may not have
picked the most representative set of test codes for your typical use and I may not have used the
very best compiler options in every case.
But I did use actual applications and simulation codes that I regularly use at work and home.
Also, I'm a reasonable
programmer (I know what it means to "vectorize" C programs for a Cray), but I
don't pretend to be an expert on writing super-fast, super-efficient
code. Mostly I try to write code as elegantly as possible without doing
anything that will result in an obvious performance penalty. Also, a large
fraction (approximately 2/3) of the code is from open-source libraries or
As in 2002, I received no compensation of any kind for this review,
and I have no advertising or sponsoring on my site. Opinions expressed here are purely