Random clang testing results

To follow up on this:
> Daniel Dunbar wrote:
> > I tried building Blender with clang today for fun. Went without a
> > hitch, although I had to use gcc for two files from ffmpeg with nasty
> > inline asm. Blender has about 600k lines of C code internally, and
> > another 600k from external libraries (like FFTW, ffmpeg, qhull, ...).
> How do compile times compare?

With a Release-Asserts build of clang:482.57user 34.79system 9:51.38elapsed 87%CPU (0avgtext+0avgdata0maxresident)k0inputs+0outputs (106major+10080717minor)pagefaults 0swaps

With gcc-4.3.3:714.04user 36.75system 12:28.26elapsed 100%CPU (0avgtext+0avgdata0maxresident)k0inputs+0outputs (14major+9324539minor)pagefaults 0swaps

This is a complete configure / build / install test, so there is some amountof shared overhead. The under CPU utilization is interesting, possibly dueto the driver not honoring -pipe yet.
- Daniel

Daniel,

There are 644 *.cpp files in blender.
did you use llvm-gcc for c++ comiler?
Seem like not a good basis for comparison.

2009/3/23 रजनीश <rdogra@earthlink.net>

Daniel,

There are 644 *.cpp files in blender.
did you use llvm-gcc for c++ comiler?
Seem like not a good basis for comparison.

No, I just used the default C++ compiler (g++). Seems like a perfectly reasonable comparison to me… this just means our C compiler is that much faster compared to gcc to get the overall improvement.

  • Daniel