Re: [gentoo-dev] ICC Profile

[Donnie Berkholz]

On 14:23 Thu 17 Jul     , Adam Stylinski wrote:
> The intel C Compiler (icc) has an ebuild for gentoo and the wiki has a
> script to integrate it with portage.  This script works will in terms
> of building binaries, however when mixed with gcc environments there
> are massive linking issues.  I propose that an ICC profile is made
> which contains specific versions and default flags for people who want
> to build a mixed icc-gcc environment.  ICC is much faster than GCC and
> although not free, offers a free non-commercial license.  I would be
> very interested in this project and more than willing to help to the
> best of my abilities.  I've already been trying to maintain a mixed
> environment with some luck, while there have been a lot of problems
> using dynamically linked libraries (ld from intel and ld from gcc
> don't always get along), my system is substatially faster.  The kernel
> obviously will still be built under gcc as well as bash (unless intel
> helps submit patches to make the code work with their compiler).
> There are many tools icc has to offer for vectorization.  If these
> were streamlined into Gentoo with a fetch restriction for ICC, a
> bootsrapping boot disk could be made and result in a very fast
> distribution. -- gentoo-dev@l.g.o mailing list

Adam,

I've already got a mixed system that works reasonably well. I use 
/etc/portage/env/ to control which packages build with icc and 
icc-specific CFLAGS by having /etc/portage/env/$CATEGORY/$PN be symlinks 
to /etc/portage/env/env.icc with these contents:

  echo " * Exporting: Intel compilers in $EBUILD_PHASE"
  CC="icc"
  CXX="icc"
  FC="ifort"
  F77="ifort"
  FFLAGS="-openmp -parallel -ipo -xO -O2 -no-prec-div"
  FCFLAGS="${FFLAGS}"
  
  export CC CXX FC F77 FFLAGS FCFLAGS

Is what you're proposing here an improvement over something like the 
above setup? If so, could you explain how?

-- 
Thanks,
Donnie

Donnie Berkholz
Developer, Gentoo Linux
Blog: http://dberkholz.wordpress.com