[gentoo-user] PYTHON_SINGLE_TARGET & libreoffice

[Alan McKinnon]

I don't know much about PYTHON_SINGLE_TARGET and PYTHON_TARGET, it all
seemed to just work so I never looked further. Until now. Of all
packages, libreoffice seems to want only python3:

I can set it in make.conf but as expected that causes all manner of
other packages to fail emerge checks as they need python2.7.

What's the preferred way to deal with this situation?
Some relevant info:

!!! The ebuild selected to satisfy "app-office/libreoffice" has unmet
requirements.
- app-office/libreoffice-5.1.0.3::gentoo USE="bluetooth branding cups
dbus gstreamer java kde mysql vlc (-aqua) -coinmp -collada -debug -eds
(-firebird) -gltf -gnome -gtk -gtk3 -jemalloc -libressl -odk -postgres
(-telepathy) -test" ABI_X86="64" LIBREOFFICE_EXTENSIONS="-nlpsolver
-scripting-beanshell -scripting-javascript -wiki-publisher"
PYTHON_SINGLE_TARGET="-python3_4 -python3_5" PYTHON_TARGETS="python3_4
python3_5"

  The following REQUIRED_USE flag constraints are unsatisfied:
    exactly-one-of ( python_single_target_python3_4
python_single_target_python3_5 )


khamul ~ # eix -e python
[I] dev-lang/python
     Available versions:
     (2.7)  2.7.10-r1 (~)2.7.11-r2
     (3.3)  3.3.5-r2 (~)3.3.5-r7(3.3/3.3m)
     (3.4)  3.4.3-r1 (~)3.4.3-r7(3.4/3.4m)
     (3.5)  (~)3.5.0-r2 (~)3.5.1-r2(3.5/3.5m)
       {-berkdb build doc examples gdbm hardened ipv6 libressl +ncurses
+readline sqlite +ssl +threads tk +wide-unicode wininst +xml ELIBC="uclibc"}
     Installed versions:  2.7.11-r2(2.7)(23:48:21 11/01/2016)(gdbm ipv6
ncurses readline sqlite ssl threads wide-unicode xml -berkdb -build -doc
-examples -hardened -libressl -tk -wininst ELIBC="-uclibc")
3.4.3-r7(3.4)(12:59:30 01/01/2016)(gdbm ipv6 ncurses readline sqlite ssl
threads xml -build -examples -hardened -libressl -tk -wininst
ELIBC="-uclibc") 3.5.1-r2(3.5)(19:42:48 27/02/2016)(gdbm ipv6 ncurses
readline sqlite ssl threads xml -build -examples -hardened -libressl -tk
-wininst ELIBC="-uclibc")
     Homepage:            http://www.python.org/
     Description:         An interpreted, interactive, object-oriented
programming language


khamul ~ # eselect python list
Available Python interpreters:
  [1]   python2.7
  [2]   python3.4
  [3]   python3.5 *


khamul ~ # emerge --info | grep PYTHON
PYTHON_SINGLE_TARGET="python2_7"
PYTHON_TARGETS="python2_7 python3_4"
Unset:  USE_PYTHON


-- 
Alan McKinnon
alan.mckinnon@×××××.com