Portage - qtcore qtdbus, and qtgui slot conflicts

I've been trying to get a DE working on Gentoo. First I installed KDE 4 because I didn't realise KDE 5 packages were named plasma. Then I uninstalled KDE 4 and switched to the plasma profile. Next I tried to reinstall all packages with the USE flags of the new profile using the following command (with output):
` # emerge --newuse --deep --verbose-conflicts @world
Calculating dependencies .. .. .... done!
[ebuild R ] sys-apps/sandbox-2.10-r1 USE="(multilib*)"
[ebuild N ] dev-libs/libnatspec-0.2.6-r1 USE="-doc -python" PYTHON_TARGETS="python2_7"
[ebuild R ] app-arch/unzip-6.0-r3 USE="natspec*"
[ebuild N ] dev-libs/icu-55.1 USE="-debug -doc -examples -static-libs" ABI_X86="(64) -32 (-x32)"
[ebuild N ] x11-libs/libxkbcommon-0.5.0 USE="X -doc -static-libs {-test}" ABI_X86="(64) -32 (-x32)"
[ebuild N ] dev-libs/wayland-1.9.0 USE="-doc -static-libs" ABI_X86="(64) -32 (-x32)"
[ebuild R ] x11-libs/libXfont-1.5.1 USE="truetype*"
[ebuild R ] media-fonts/font-misc-misc-1.1.2 USE="X*"
[ebuild R ] dev-qt/qtcore-4.8.6-r2 USE="icu*"
[ebuild N ] net-mail/mailbase-1.1 USE="pam"
[ebuild N ] dev-libs/cyrus-sasl-2.1.26-r9 USE="berkdb gdbm pam ssl -authdaemond -java -kerberos -ldapdb -mysql -openldap -postgres -sample (-selinux) -sqlite -srp -static-libs -urandom" ABI_X86="(64) -32 (-x32)"
[ebuild NS ] dev-qt/qtcore-5.4.2 [4.8.6-r2] USE="icu -debug -systemd {-test}"
[ebuild NS ~] dev-qt/qtcore-5.5.1-r1 [4.8.6-r2] USE="icu -debug -systemd {-test}"
[ebuild N ] dev-qt/qtnetwork-5.4.2 USE="bindist ssl -connman -debug -networkmanager {-test}"
[ebuild NS ] dev-qt/qtdbus-5.4.2 [4.8.6-r1] USE="-debug {-test}"
[ebuild NS ~] dev-qt/qtdbus-5.5.1 [4.8.6-r1] USE="-debug {-test}"
[ebuild N ] dev-qt/qtxml-5.4.2 USE="-debug {-test}"
[ebuild NS ] dev-qt/qttest-5.4.2 [4.8.6-r1] USE="-debug {-test}"
[ebuild N ] dev-qt/qtconcurrent-5.4.2 USE="-debug {-test}"
[ebuild NS ] dev-qt/qtxmlpatterns-5.4.2 [4.8.6-r1] USE="-debug {-test}"
[ebuild R ] sys-apps/groff-1.22.2 USE="X*"
[ebuild R ] dev-libs/gobject-introspection-1.46.0 USE="cairo*"
[ebuild NS ] dev-qt/qtgui-5.4.2-r1 [4.8.6-r4] USE="dbus gif harfbuzz jpeg png udev xcb -accessibility -debug -egl -eglfs -evdev -gles2 -gtkstyle -ibus {-test}"
[ebuild NS ~] dev-qt/qtgui-5.5.1-r1 [4.8.6-r4] USE="dbus gif jpeg png udev xcb -accessibility -debug -egl -eglfs -evdev -gles2 -gtkstyle -ibus -libinput {-test} -tslib -tuio"
[ebuild N ] dev-qt/qtwidgets-5.4.2 USE="png xcb -debug -gles2 -gtkstyle {-test}"
[ebuild N ~] dev-qt/qtx11extras-5.5.1 USE="-debug {-test}"
[ebuild NS ] dev-qt/qtdeclarative-5.4.2-r1 [4.8.6-r1] USE="jit widgets xml -debug -gles2 -localstorage {-test}"
[ebuild N ] dev-qt/qtprintsupport-5.4.2 USE="cups -debug -gles2 {-test}"
[ebuild NS ] dev-qt/qtsvg-5.4.2 [4.8.6-r1] USE="-debug {-test}"
[ebuild NS ] dev-qt/designer-5.4.2 [4.8.6-r1] USE="declarative -debug {-test} -webkit"
[ebuild R ] sys-auth/pambase-20150213 USE="consolekit*"
[ebuild R ] net-misc/openssh-7.1_p2 USE="X* ldap*"
[ebuild R ] sys-libs/ncurses-5.9-r5 USE="gpm*"
[ebuild R ] sys-libs/ncurses-5.9-r99 USE="gpm*"
[ebuild R ] sys-apps/util-linux-2.26.2 USE="udev*"
[ebuild R ] dev-util/cmake-3.3.1-r1 USE="qt5* -qt4*"
[ebuild R ] x11-terms/xterm-320 USE="truetype*"
[ebuild R ] net-wireless/wpa_supplicant-2.5-r1 USE="qt5* -qt4*"
[ebuild R ] sys-auth/polkit-qt-0.112.0-r1 USE="qt5*"
[ebuild R ] app-text/poppler-0.32.0 USE="qt5*"
[ebuild R ] sys-process/psmisc-22.21-r2 USE="X*"
[ebuild R ] app-crypt/qca-2.1.0.3 USE="qt5*"
[ebuild R ] dev-libs/libdbusmenu-qt-0.9.3_pre20140619-r1 USE="qt5*"
[ebuild R ] www-client/links-2.8-r1 USE="X* gpm* jpeg* tiff*"
[ebuild R ] sys-auth/polkit-kde-agent-0.99.1-r1 USE="minimal*"
[ebuild R ] sys-boot/grub-2.02_beta2-r8 [2.02_beta2-r8] USE="sdl* truetype*"
[ebuild R ~] sys-kernel/git-sources-4.5_rc6 USE="-symlink*"
[ebuild R ] app-admin/sudo-1.8.15-r1 USE="ldap*"
[ebuild R ] media-libs/phonon-4.7.2 USE="qt5*"
[ebuild R ] media-libs/phonon-vlc-0.7.2 USE="qt5*"
[ebuild R ] media-video/vlc-2.2.1-r1 USE="qt5* -qt4*"
[ebuild R ] sys-libs/glibc-2.21-r2 USE="(multilib*)"
[ebuild R ] sys-devel/gcc-4.9.3 USE="(multilib*)"
[ebuild R ] sys-devel/llvm-3.5.0 USE="xml*"
[ebuild R ] media-libs/mesa-11.0.6 USE="wayland*"

!!! Multiple package instances within a single package slot have been pulled
!!! into the dependency graph, resulting in a slot conflict:

dev-qt/qtgui:5

(dev-qt/qtgui-5.5.1-r1:5/5::gentoo, ebuild scheduled for merge) pulled in by
~dev-qt/qtgui-5.5.1[xcb] required by (dev-qt/qtx11extras-5.5.1:5/5::gentoo, ebuild scheduled for merge)
^ ^^^^^

(dev-qt/qtgui-5.4.2-r1:5/5::gentoo, ebuild scheduled for merge) pulled in by
~dev-qt/qtgui-5.4.2[gles2=] required by (dev-qt/qtprintsupport-5.4.2:5/5::gentoo, ebuild scheduled for merge)
^ ^^^^^
~dev-qt/qtgui-5.4.2[gles2=,gtkstyle=,png=,xcb?] required by (dev-qt/qtwidgets-5.4.2:5/5::gentoo, ebuild scheduled for merge)
^ ^^^^^

dev-qt/qtdbus:5

(dev-qt/qtdbus-5.5.1:5/5::gentoo, ebuild scheduled for merge) pulled in by
~dev-qt/qtdbus-5.5.1 required by (dev-qt/qtgui-5.5.1-r1:5/5::gentoo, ebuild scheduled for merge)
^ ^^^^^

(dev-qt/qtdbus-5.4.2:5/5::gentoo, ebuild scheduled for merge) pulled in by
~dev-qt/qtdbus-5.4.2 required by (dev-qt/qtgui-5.4.2-r1:5/5::gentoo, ebuild scheduled for merge)
^ ^^^^^

dev-qt/qtcore:5

(dev-qt/qtcore-5.5.1-r1:5/5::gentoo, ebuild scheduled for merge) pulled in by
~dev-qt/qtcore-5.5.1 required by (dev-qt/qtgui-5.5.1-r1:5/5::gentoo, ebuild scheduled for merge)
^ ^^^^^
~dev-qt/qtcore-5.5.1 required by (dev-qt/qtx11extras-5.5.1:5/5::gentoo, ebuild scheduled for merge)
^ ^^^^^
~dev-qt/qtcore-5.5.1 required by (dev-qt/qtdbus-5.5.1:5/5::gentoo, ebuild scheduled for merge)
^ ^^^^^

(dev-qt/qtcore-5.4.2:5/5::gentoo, ebuild scheduled for merge) pulled in by
~dev-qt/qtcore-5.4.2 required by (dev-qt/qtdbus-5.4.2:5/5::gentoo, ebuild scheduled for merge)
^ ^^^^^
~dev-qt/qtcore-5.4.2 required by (dev-qt/qtconcurrent-5.4.2:5/5::gentoo, ebuild scheduled for merge)
^ ^^^^^
~dev-qt/qtcore-5.4.2 required by (dev-qt/qtwidgets-5.4.2:5/5::gentoo, ebuild scheduled for merge)
^ ^^^^^
~dev-qt/qtcore-5.4.2 required by (dev-qt/qtnetwork-5.4.2:5/5::gentoo, ebuild scheduled for merge)
^ ^^^^^
~dev-qt/qtcore-5.4.2 required by (dev-qt/qtxml-5.4.2:5/5::gentoo, ebuild scheduled for merge)
^ ^^^^^
~dev-qt/qtcore-5.4.2 required by (dev-qt/qtprintsupport-5.4.2:5/5::gentoo, ebuild scheduled for merge)
^ ^^^^^
~dev-qt/qtcore-5.4.2 required by (dev-qt/qttest-5.4.2:5/5::gentoo, ebuild scheduled for merge)
^ ^^^^^
~dev-qt/qtcore-5.4.2 required by (dev-qt/qtgui-5.4.2-r1:5/5::gentoo, ebuild scheduled for merge)
^ ^^^^^

It may be possible to solve this problem by using package.mask to
prevent one of those packages from being selected. However, it is also
possible that conflicting dependencies exist such that they are
impossible to satisfy simultaneously. If such a conflict exists in
the dependencies of two different packages, then those packages can
not be installed simultaneously. You may want to try a larger value of
the --backtrack option, such as --backtrack=30, in order to see if
that will solve this conflict automatically.

For more information, see MASKED PACKAGES section in the emerge man
page or refer to the Gentoo Handbook. `

It seems like portage wants to install multiple versions of the aforementioned packages. Does anyone know what I can do about this?

Remove all the qt!

Following this guide https://wiki.gentoo.org/wiki/Qt/FAQ

Id suggest using qt from the overlay so heres slightly modified version that just removes qt.

  1. List all installed qt packages:
 root # export INSTALLED_QT_PACKAGES=$(eix --only-names -IC dev-qt)
  1. Save tarballs of the old versions should we have to roll back:
 root # quickpkg ${INSTALLED_QT_PACKAGES}
  1. old version and emerge new version:
 root # emerge -Ca ${INSTALLED_QT_PACKAGES}

Note
the eix command is provided by app-portage/eix

Then install qt from the qt overlay, i've found this the best way to manage qt in Gentoo as the overlay has nice sets for it.

layman -a qt

emerge -av @qt5-essentials @qt5-addons

Thanks for the suggestion but my system seems to have gone to fuck in the meantime. I am now unable to login and when I try to run anything with emerge it tells me that there is a problem with the sandbox binary. Even when I run it with "FEATURES=-sandbox". It doesn't even want to show any man pages. I think I might just reinstall Gentoo and copy over my kernel .config file