Re: [gentoo-user] update problems

[Mick]

On Saturday 19 Sep 2015 21:05:27 Neil Bothwick wrote:
> On Sat, 19 Sep 2015 21:36:06 +0200, lee wrote:
> > emerge -j 8 -a --update --newuse --deep --with-bdeps=y
> > @world
> >
> >  * IMPORTANT: 4 news items need reading for repository 'gentoo'.
> >  * Use eselect news read to view new items.
> >
> > These are the packages that would be merged, in order:
> >
> > Calculating dependencies... done!
> >
> > !!! Multiple package instances within a single package slot have been
> > pulled !!! into the dependency graph, resulting in a slot conflict:
> >
> > dev-libs/boost:0
> >
> >   (dev-libs/boost-1.56.0-r1:0/1.56.0::gentoo, ebuild scheduled for
> >
> > merge) pulled in by (no parents that aren't satisfied by other packages
> > in this slot)
> >
> >   (dev-libs/boost-1.55.0-r2:0/1.55.0::gentoo, ebuild scheduled for
> >
> > merge) pulled in by dev-libs/boost:0/1.55.0= required by
> > (dev-libs/librevenge-0.0.2:0/0::gentoo, installed)
> > ^^^^^^^^^^ (and 2 more with the same problem)
> >
> > dev-util/boost-build:0
> >
> >   (dev-util/boost-build-1.55.0:0/0::gentoo, installed) pulled in by
> >
> >     =dev-util/boost-build-1.55* required by
> >
> > (dev-libs/boost-1.55.0-r2:0/1.55.0::gentoo, ebuild scheduled for merge)
> > ^
> > ^^^^^
> >
> >   (dev-util/boost-build-1.56.0:0/0::gentoo, ebuild scheduled for merge)
> >
> > pulled in by =dev-util/boost-build-1.56* required by
> > (dev-libs/boost-1.56.0-r1:0/1.56.0::gentoo, ebuild scheduled for merge)
> > ^
> > ^^^^^
> >
> > media-video/ffmpeg:0
> >
> >   (media-video/ffmpeg-2.6.3:0/54.56.56::gentoo, ebuild scheduled for
> >
> > merge) pulled in by (no parents that aren't satisfied by other packages
> > in this slot)
> >
> >   (media-video/ffmpeg-2.2.14:0/52.55.55::gentoo, installed) pulled in by
> >
> >     media-video/ffmpeg:0/52.55.55=[vdpau] required by
> >
> > (media-libs/mlt-0.9.0:0/0::gentoo, installed)
> > ^^^^^^^^^^^
>
> These are unimportant, it is simply portage telling you it is not
> updating some packages to the latest available and why. Personally, I
> believe this sort of output should only be shown when using --verbose.
>
> > 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.
> >
> > For more information, see MASKED PACKAGES section in the emerge man
> > page or refer to the Gentoo Handbook.
> >
> >
> > !!! The ebuild selected to satisfy "sci-libs/hdf5" has unmet
> > requirements.
> > - sci-libs/hdf5-1.8.14-r1::gentoo USE="cxx fortran threads zlib -debug
> > -examples -fortran2003 -mpi -static-libs -szip"
> >
> >   The following REQUIRED_USE flag constraints are unsatisfied:
> >     threads? ( !cxx !fortran )
>
> This is blocking you and the reason is given, if you have the threads
> flag on, cxx and fortran must be off. You have both threads and cxx on
> which won't work.
>
> > Why can't we just update like we can with any other distribution but
> > have to run into dependency problems all the time instead?
>
> These aren't dependency problems, they are conflicting USE flags, a
> situation that cannot arise with a binary distro. If you want the
> flexibility that USE flags offer, you have to accept that not all
> combinations will work together.
>
> > What do I do when I need to update /right now/ and find myself being
> > blocked with cryptic messages like the above that leave me stranded?
>
> That's the real problem, that the messages are so cryptic. The solution
> is simple, working out what needs to be done from the messages is not.
>
> > Once I used 'emerge --sync', there is no way to turn it back to continue
> > to be able to install software if needed when the update cannot be
> > performed.  Updates simply need to work, there's no way around that.
>
> You can always roll back by masking the updates if necessary, and the
> old ebuilds are always available. Now that the tree is using git, it is
> probably possibly to sync back to yesterday if you need to.

As Alan said quickpkg boost, remove boost-1.55.0-r2, install boost-1.56.0-r1, 
emerge -1aDv dev-libs/librevenge and which-ever other package complains and 
you should be OK.  Apply a similar approach with ffmpeg.

Neil's comments on sci-libs/hdf5 stand.

-- 
Regards,
Mick