libpostproc52:i386 fails to upgrade to libpostproc52:amd64 on multi-arch systems

[Kosmas Chatzimichalis]

TEST CASE:
1. On a fresh saucy amd64 environment, enable multiarch
2. Install the following packages:
$ apt-get install gstreamer0.10-ffmpeg libpostproc52:i386
3. Upgrade

ACTUAL RESULT:
Upgrade fails with:
dpkg: error processing archive /var/cache/apt/archives/libpostproc52_6%3a0.git20120821-4_amd64.deb (--unpack):
 libpostproc52:amd64 6:0.git20120821-4 (Multi-Arch: no) is not co-installable with libpostproc52 which has multiple installed instances

== Original Report ==
When doing a system upgrade from 13.10 to 14.04 the message:

Could not install '/var/cache/apt/archives/libpostproc52_6%3a0.git20120821-4_amd64.deb'
The upgrade will continue but the '/var/cache/apt/archives/libpostproc52_6%3a0.git20120821-4_amd64.deb'
package may not be in a working state. Please consider submiting a bug report about it.
---
ApportVersion: 2.14.1-0ubuntu3
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: KDE
DistroRelease: Ubuntu 14.04
InstallationDate: Installed on 2013-12-17 (141 days ago)
InstallationMedia: Kubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1)
Package: ubuntu-release-upgrader (not installed)
ProcVersionSignature: Ubuntu 3.13.0-24.47-generic 3.13.9
Tags: trusty dist-upgrade
Uname: Linux 3.13.0-24-generic x86_64
UpgradeStatus: Upgraded to trusty on 2014-05-06 (1 days ago)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo vboxusers
_MarkForUpload: True

[Brian Murray (brian-murray)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. Please execute the following command, as it will automatically gather debugging information, in a terminal:

  apport-collect 1316789

When reporting bugs in the future please use apport by using 'ubuntu-bug' and the name of the package affected. You can learn more about this functionality at https://wiki.ubuntu.com/ReportingBugs.

[Kosmas Chatzimichalis (kosmas)]

apport information

[Kosmas Chatzimichalis (kosmas)]

apport information

[Kosmas Chatzimichalis (kosmas)]

apport information

[Kosmas Chatzimichalis (kosmas)]

apport information

[Kosmas Chatzimichalis (kosmas)]

apport information

[Kosmas Chatzimichalis (kosmas)]

apport information

[Kosmas Chatzimichalis (kosmas)]

apport information

[Kosmas Chatzimichalis (kosmas)]

apport information

[Kosmas Chatzimichalis (kosmas)]

apport information

[Jean-Baptiste Lallement (jibel)]

Thanks for your report.

This is because the upgrader decides to replace libpostproc52:i386 by libpostproc52:amd64 and fails because they are not co-installable and dpkg thinks i386 is still installed while it has been removed earlier.

The relevant parts of term.log are:
Removing libpostproc52:i386 (6:0.8.10-0ubuntu0.13.10.1) ...
Processing triggers for libc-bin (2.19-0ubuntu6) ...
--
Unpacking libmtp9:amd64 (1.1.6-20-g1b9f164-1ubuntu2) over (1.1.6-2) ...
dpkg: error processing archive /var/cache/apt/archives/libpostproc52_6%3a0.git20120821-4_amd64.deb (--unpack):
 libpostproc52:amd64 6:0.git20120821-4 (Multi-Arch: no) is not co-installable with libpostproc52 which has multiple installed instances
Preparing to unpack .../libssh2-1_1.4.3-2_amd64.deb ...
--
Errors were encountered while processing:
 /var/cache/apt/archives/libpostproc52_6%3a0.git20120821-4_amd64.deb
dpkg: tk-lib:amd64: dependency problems, but removing anyway as you requested:
--
Setting up libmtp9:amd64 (1.1.6-20-g1b9f164-1ubuntu2) ...
dpkg: error processing package libpostproc52:amd64 (--configure):
 package libpostproc52:amd64 is already installed and configured
Setting up libssh2-1:amd64 (1.4.3-2) ...
--
Errors were encountered while processing:
 libpostproc52:amd64

And from main.log
     MarkDelete xserver-xorg-glamoregl [ amd64 ] < 0.5.1-0ubuntu4.2 > ( x11 ) FU=0
  MarkInstall libpostproc52 [ amd64 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
   Removing: libpostproc52
    MarkDelete libpostproc52 [ i386 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
  MarkInstall libpostproc52 [ i386 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
   Removing: libpostproc52
    MarkDelete libpostproc52 [ amd64 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
  MarkInstall libfftw3-3 [ amd64 ] < 3.3.3-5ubuntu1 -> 3.3.3-7ubuntu3 > ( universe/libs ) FU=0
--
  MarkInstall gstreamer0.10-ffmpeg [ amd64 ] < 0.10.13-5 > ( libs ) FU=0
  Installing libpostproc52 as Depends of gstreamer0.10-ffmpeg
    MarkInstall libpostproc52 [ amd64 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
     Removing: libpostproc52
      MarkDelete libpostproc52 [ i386 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
  MarkInstall gstreamer0.10-ffmpeg [ i386 ] < 0.10.13-5 > ( libs ) FU=0
  Installing libpostproc52 as Depends of gstreamer0.10-ffmpeg
    MarkInstall libpostproc52 [ i386 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
     Removing: libpostproc52
      MarkDelete libpostproc52 [ amd64 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs ) FU=0
  MarkInstall rsyslog [ amd64 ] < 5.8.11-2ubuntu4 -> 7.4.4-1ubuntu2 > ( admin ) FU=0
--
  Fixing ubuntu-drivers-common:amd64 via remove of jockey-kde:amd64
Investigating (0) libpostproc52 [ amd64 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs )
Broken libpostproc52:amd64 Conflicts on libpostproc52 [ i386 ] < 6:0.8.10-0ubuntu0.13.10.1 -> 6:0.git20120821-4 > ( universe/libs )
  Consid...