The intel compiler support slotted installation, but they only install one env.d file. So the slotting is of no need. Here what sebastien says: The initial idea was to indeed maintain a eselect-icc that could easily switch between versions. The work to do on the Intel stuff is the following. dev-lang/icc, dev-lang/ifc, dev-lang/idb, sci-libs/mkl, sci-libs/ipp and may be dev-cpp/tbb would have to be slotted simultaneously with probably a common eselect mechanism. The thing to do might be to not install the 35intelsdp, and have an eselect intel module that will link shell scripts to a /etc/profile.d/ So we also avoid env variables pollution, and users could source it [1] [1] https://bugs.gentoo.org/show_bug.cgi?id=346723
