Title: Restructuring of mips profiles
Author: Anthony G. Basile <blueness@gentoo.org>
Content-Type: text/plain
Posted: 2014-10-04
Revision: 1
News-Item-Format: 1.0
Display-If-Keyword: mips
Display-If-Installed: sys-libs/glibc

To accomodate the new multilib approach in Gentoo, the mips profiles will be
changing on Oct 11, 2014.  The new profile structure will be as follows:

  [1]   default/linux/mips/13.0/o32
  [2]   default/linux/mips/13.0/n32
  [3]   default/linux/mips/13.0/n64
  [4]   default/linux/mips/13.0/multilib/o32
  [5]   default/linux/mips/13.0/multilib/n32
  [6]   default/linux/mips/13.0/multilib/n64
  [7]   default/linux/mips/13.0/mipsel/o32
  [8]   default/linux/mips/13.0/mipsel/n32
  [9]   default/linux/mips/13.0/mipsel/n64
  [10]  default/linux/mips/13.0/mipsel/multilib/o32
  [11]  default/linux/mips/13.0/mipsel/multilib/n32
  [12]  default/linux/mips/13.0/mipsel/multilib/n64
  [13]  hardened/linux/musl/mips
  [14]  hardened/linux/musl/mips/mipsel
  [15]  default/linux/uclibc/mips
  [16]  hardened/linux/uclibc/mips
  [17]  default/linux/uclibc/mips/mipsel
  [18]  hardened/linux/uclibc/mips/mipsel

There are a few points to note about the change:

1) Only the glibc profiles (1-12) are affected.  The embedded system profiles 
(13-18) will not change.

2) The glibc profiles will now explicitly state the ABIs.  In the case of
non-multilib systems (1-3, 7-9) the stated ABI will be the only ABI available,
while in the case of multilib systems (4-6, 10-12) the stated ABI will be the
default ABI, and the others will be available by setting ABI_MIPS in make.conf.

3) Profiles 1 and 7 are strictly 32-bit userland, but can run under either a
32-bit or 64-bit kernel.  They will have CHOST = mips-unknown-linux-gnu and
mipsel-unknown-linux-gnu, respectively.  All the other glibc profiles (2-6, 8-12)
are 64-bits userland and will have CHOST = mips64-unknown-linux-gnu or
mips64el-unknown-linux-gnu.

4) Only users of profiles 1 and 7 need to change their profiles sym links using
`eselect profile`.  However, all users should be aware of the CHOST value on
their system to ensure it remains unchanged after the profile updates.