~ $ su -
Password: 
~ # rm -r /var/portage/distfiles/* /var/portage/packages/* /var/tmp/portage/*
rm: cannot remove '/var/portage/packages/*': No such file or directory
rm: cannot remove '/var/tmp/portage/*': No such file or directory
~ # export XDG_DESKTOP_DIR="/root/Desktop"
~ # export XDG_DOCUMENTS_DIR="/root/Documents"
~ # export XDG_DOWNLOAD_DIR="/root/Downloads"
~ # export XDG_MUSIC_DIR="/root/Music"
~ # export XDG_PICTURES_DIR="/root/Pictures"
~ # export XDG_PUBLICSHARE_DIR="/root/Public"
~ # export XDG_TEMPLATES_DIR="/root/Templates"
~ # export XDG_VIDEOS_DIR="/root/Videos"
~ # export XDG_RUNTIME_DIR="/root/run"
~ # export XDG_CONFIG_HOME="/root/config"
~ # export XDG_CACHE_HOME="/root/cache"
~ # export XDG_DATA_HOME="/root/share"
~ # FEATURES="xattr preserve-libs parallel-fetch ipc-sandbox network-sandbox -news" emerge -1v --quiet-build=n =app-shells/mpv-bash-completion-3.3.13

These are the packages that would be merged, in order:

Calculating dependencies... done!
[ebuild     UD~] app-shells/mpv-bash-completion-3.3.13::gentoo [9999::bonespirit] USE="luajit" 20 KiB

Total: 1 package (1 downgrade), Size of downloads: 20 KiB


>>> Verifying ebuild manifests
                                                                                         
>>> Emerging (1 of 1) app-shells/mpv-bash-completion-3.3.13::gentoo                      
>>> Downloading 'http://mirror.yandex.ru/gentoo-distfiles/distfiles/mpv-bash-completion-3.3.13.tar.gz'
--2017-04-17 12:59:05--  http://mirror.yandex.ru/gentoo-distfiles/distfiles/mpv-bash-completion-3.3.13.tar.gz
Resolving mirror.yandex.ru (mirror.yandex.ru)... 213.180.204.183, 2a02:6b8::183          
Connecting to mirror.yandex.ru (mirror.yandex.ru)|213.180.204.183|:80... connected.      
HTTP request sent, awaiting response... 200 OK                                           
Length: 19726 (19K) [application/octet-stream]                                           
Saving to: ‘/var/portage/distfiles/mpv-bash-completion-3.3.13.tar.gz’                    
                                                                                         
/var/portage/distfi 100%[===================>]  19,26K  --.-KB/s    in 0,03s             
                                                                                         
2017-04-17 12:59:05 (641 KB/s) - ‘/var/portage/distfiles/mpv-bash-completion-3.3.13.tar.gz’ saved [19726/19726]
                                                                                         
 * mpv-bash-completion-3.3.13.tar.gz SHA256 SHA512 WHIRLPOOL size ;-) ...                                                                                                   [ ok ]
>>> Unpacking source...                                                                  
>>> Unpacking mpv-bash-completion-3.3.13.tar.gz to /var/tmp/portage/app-shells/mpv-bash-completion-3.3.13/work
>>> Source unpacked in /var/tmp/portage/app-shells/mpv-bash-completion-3.3.13/work       
>>> Preparing source in /var/tmp/portage/app-shells/mpv-bash-completion-3.3.13/work/mpv-bash-completion-3.3.13 ...
>>> Source prepared.                                                                     
>>> Configuring source in /var/tmp/portage/app-shells/mpv-bash-completion-3.3.13/work/mpv-bash-completion-3.3.13 ...
>>> Source configured.                                                                   
>>> Compiling source in /var/tmp/portage/app-shells/mpv-bash-completion-3.3.13/work/mpv-bash-completion-3.3.13 ...
>>> Source compiled.                                                                     
>>> Test phase [not enabled]: app-shells/mpv-bash-completion-3.3.13                      
                                                                                         
>>> Install mpv-bash-completion-3.3.13 into /var/tmp/portage/app-shells/mpv-bash-completion-3.3.13/image/ category app-shells
>>> Completed installing mpv-bash-completion-3.3.13 into /var/tmp/portage/app-shells/mpv-bash-completion-3.3.13/image/
                                                                                         
 * Final size of build directory: 168 KiB                                                
 * Final size of installed tree: 112 KiB

ecompressdir: bzip2 -9 /usr/share/doc

>>> Installing (1 of 1) app-shells/mpv-bash-completion-3.3.13::gentoo
 * checking 2 files for package collisions
>>> Merging app-shells/mpv-bash-completion-3.3.13 to /
--- /usr/
--- /usr/share/
--- /usr/share/bash-completion/
--- /usr/share/bash-completion/completions/
>>> /usr/share/bash-completion/completions/mpv
--- /usr/share/doc/
>>> /usr/share/doc/mpv-bash-completion-3.3.13/
>>> /usr/share/doc/mpv-bash-completion-3.3.13/README.mkd.bz2
>>> Safely unmerging already-installed instance...
No package files given... Grabbing a set.
<<<          obj /usr/share/doc/mpv-bash-completion-9999/README.mkd.bz2
--- replaced dir /usr/share/doc
--- replaced obj /usr/share/bash-completion/completions/mpv
--- replaced dir /usr/share/bash-completion/completions
--- replaced dir /usr/share/bash-completion
--- replaced dir /usr/share
--- replaced dir /usr
<<<          dir /usr/share/doc/mpv-bash-completion-9999
>>> Regenerating /etc/ld.so.cache...
>>> Original instance of package unmerged safely.
>>> app-shells/mpv-bash-completion-3.3.13 merged.
>>> Auto-cleaning packages...

>>> No outdated packages were found on your system.

 * GNU info directory index is up-to-date.
~ # ls -la /root/cache /root/.cache
ls: cannot access '/root/cache': No such file or directory
ls: cannot access '/root/.cache': No such file or directory