Re: [gentoo-user] re: resolving blocked packages [media-video/ffmpeg-1.2:0]

[Alan McKinnon <alan.mckinnon@gmail.com>]

On 02/11/2013 12:49, Daniel Campbell wrote:
> On 10/27/2013 12:08 PM, Alexander Kapshuk wrote:
>> As I ran 'emerge --ask --update --deep --with-bdeps=y --newuse world', I
>> got the message below.
>>
>> These are the packages that would be merged, in order:
>>
>> Calculating dependencies... done!
>> [ebuild  N     ] dev-scheme/guile-1.8.8-r1  USE="deprecated nls regex
>> threads -debug -debug-freelist -debug-malloc -discouraged -emacs
>> -networking"
>> [ebuild  N     ] sys-devel/autogen-5.15
>> [ebuild     U ~] net-libs/gnutls-3.2.5 [2.12.23-r1] USE="-dane%"
>> LINGUAS="-cs% -de% -en% -fi% -fr% -it% -ms% -nl% -pl% -sv% -uk% -vi%
>> -zh_CN%"
>> [ebuild  N     ] media-libs/libpostproc-0.8.0.20121125  USE="-3dnow
>> (-altivec) -mmx -mmxext -pic -static-libs"
>> [ebuild     U ~] media-video/vlc-2.1.0 [2.0.9] USE="-chromaprint% -fdk%
>> -opencv% (-qt5) -rdp% {-test%} -vdpau%"
>> [blocks B      ] <media-video/ffmpeg-1.2:0 ("<media-video/ffmpeg-1.2:0"
>> is blocking media-video/vlc-2.1.0)
>> [blocks B      ] media-video/ffmpeg:0 ("media-video/ffmpeg:0" is
>> blocking media-libs/libpostproc-0.8.0.20121125)
>> [blocks B      ] media-libs/libpostproc ("media-libs/libpostproc" is
>> blocking media-video/ffmpeg-1.0.7)
>>
>> !!! Multiple package instances within a single package slot have been pulled
>> !!! into the dependency graph, resulting in a slot conflict:
>>
>> net-libs/gnutls:0
>>
>>   (net-libs/gnutls-3.2.5::gentoo, ebuild scheduled for merge) pulled in by
>>     >=net-libs/gnutls-3.0.20:0 required by
>> (media-video/vlc-2.1.0::gentoo, ebuild scheduled for merge)
>>
>>   (net-libs/gnutls-2.12.23-r1::gentoo, installed) pulled in by
>>     (no parents that aren't satisfied by other packages in this slot)
>>
>>
>> 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.
>>
>>
>>  * Error: The above package list contains packages which cannot be
>>  * installed at the same time on the same system.
>>
>>   (media-video/vlc-2.1.0::gentoo, ebuild scheduled for merge) pulled in by
>>     media-video/vlc required by @selected
>>
>>   (media-video/ffmpeg-1.0.7::gentoo, installed) pulled in by
>>    
>>> =media-video/ffmpeg-0.10.3:0[X?,encode?,gsm?,jpeg2k?,mp3?,sdl?,speex?,theora?,threads?,truetype?,vaapi?,vdpau?,x264?]
>> (>=media-video/ffmpeg-0.10.3:0[X,encode,mp3,sdl,truetype,x264]) required
>> by (virtual/ffmpeg-0.10.3::gentoo, installed)
>>
>>
>> For more information about Blocked Packages, please refer to the following
>> section of the Gentoo Linux x86 Handbook (architecture is irrelevant):
>>
>> http://www.gentoo.org/doc/en/handbook/handbook-x86.xml?full=1#blocked
>>
>>
>> The following keyword changes are necessary to proceed:
>>  (see "package.accept_keywords" in the portage(5) man page for more details)
>> # required by media-video/vlc-2.1.0[gnutls]
>> # required by @selected
>> # required by @world (argument)
>> =net-libs/gnutls-3.2.5 ~x86
>>
>> Use --autounmask-write to write changes to config files (honoring
>> CONFIG_PROTECT). Carefully examine the list of proposed changes,
>> paying special attention to mask or keyword changes that may expose
>> experimental or unstable packages.
>> ----------------------------------------------
>> After reading the 'Blocked Packages' found here,
>> http://www.gentoo.org/doc/en/handbook/handbook-x86.xml?full=1#blocked,
>> would updating media-video/ffmpeg to version 1.2 [the current version of
>> ffmpeg is 1.0.7], fix the blockage?
>>
>> Any input would be much appreciated.
>>
>>
> 
> It looks like you just need to add `net-libs/gnutls` to
> /etc/portage/package.accept_keywords, which will fetch the testing
> version of gnutls. Is your version of vlc also from testing? That may be
> why emerge is complaining. I also noticed a lot of -USE% flags, which
> tells me they were removed. Did you change USE flags at the same time
> you attempted this update? There's no problem with that, of course, but
> it can complicate upgrades sometimes. :)
> 
> Hope that helps.
> 


The basic problem is a stable system with a bunch of unstable packages
installed.

The requested vlc version is ~arch, which wants a ~arch version of
gnutls. This conflicts with other stable packages that want a stable
version of gnutls.

Mixing and matching arch and ~arch like this often causes unsolveable
problems, especially with basic libs like gnutls used by lots of
packages. In this specific case, I doubt very much that the problem is
solveable. Either make the entire system ~arch or downgrade vlc to
stable. Mixing is not recommended, not that it won't work (it often
does), but because users so often run into these problems and devs
usually will not help fix it. The user is thus totally on tehir own with
this one.


-- 
Alan McKinnon
alan.mckinnon@gmail.com