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. 
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