Emerge on Gentoo fails with "Multiple package instances within a single package slot have been pulled … in". How can I resolve this?

Question

I'm trying to install Google Chrome on my recent Gentoo box. But emerge is throwing some errors that are way over my head. I genuinely don't know what the problem even is.

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

dev-libs/glib:2

  (dev-libs/glib-2.32.4-r1::gentoo, installed) pulled in by
    <dev-libs/glib-2.33:2 required by (dev-libs/gobject-introspection-1.32.1::gentoo, installed)

  (dev-libs/glib-2.36.4-r1::gentoo, ebuild scheduled for merge) pulled in by
    >=dev-libs/glib-2.34.0:2 required by (x11-libs/gdk-pixbuf-2.28.2::gentoo, ebuild scheduled for merge)
    (and 2 more with the same problem)

media-libs/fontconfig:1.0

  (media-libs/fontconfig-2.8.0-r1::gentoo, installed) pulled in by
    (no parents that aren't satisfied by other packages in this slot)

  (media-libs/fontconfig-2.10.92::gentoo, ebuild scheduled for merge) pulled in by
    >=media-libs/fontconfig-2.10.91:1.0= required by (x11-libs/pango-1.34.1::gentoo, ebuild scheduled for merge)

I've already tried the --backtrack=30 and --autounmask-write options as suggested in the output, but there is no difference in the output.

I just need to know what the problem is in order to go about finding a solution to it. Any help is greatly appreciated.

Solution 1

This was due to a system which was outdated. So updating it solved the issue: emerge --update --deep --with-bdeps=y --newuse @world

Solution 2

According to the Gentoo wiki page on troubleshooting, most of such cases can be resolved by emerging the latest package with, say,

emerge --ask --oneshot package-name

Comments

[derobert]

Please edit your question to include the error messages.

[Admin]

Maybe your setup is somewhat in "flux" because of some USE flag changes?... if the output suggested --autounmask-write, did you follow with dispatch-conf to update your config? Before you tried building Chrome, did you have any problem doing emerge --update --deep --with-bdeps=y --newuse @world with the emerge --depclean and revdep-rebuild commands?

[zerga]

@illuminÉ Thanks for the response. Indeed I had not updated and that was the issue. The emerge, after 2 days of updates, and headaches in between, solved the problem.

[Gherardo]

What about if the multiple instances issus is produced precisely by a emerge --update --deep --with-bdeps=y --newuse @world?

[drs]

@Gherardo wonders "What about if the multiple instances issues is produced precisely by a emerge --update --deep --with-bdeps=y --newuse @world?

[user175104]

@drs He could make a new Q and detail the issue so that anyone could contribute.

[Admin]

...the latest package in a conflicting set. My understanding is that you would have to do that for both glib and fontconfig here. I may be wrong; I cannot reproduce. +1