Bug#676496: dpkg: premature removal of "Multi-arch:" leads to all dpkg commands failing

Package: dpkg
Version: 1.16.3
Severity: grave
Justification: renders package unusable

After an interrupted dpkg run, any subsequent invocation fails with:

dpkg: error: libc6-dev:armel <none> (Multi-Arch: no) is not co-installable
with libc6-dev which has multiple installed instances

This affects not only -i, --purge, --unpack but even -l or dpkg-query.

The last two relevant entries of dpkg/updates (there's over a hundred
entries after that, none mentioning libc6-dev) are:
,--=[ /var/lib/dpkg/updates/0005
Package: libc6-dev
Status: purge ok config-files
Priority: optional
Section: libdevel
Installed-Size: 8531
Maintainer: GNU Libc Maintainers <debian-glibc@lists.debian.org>
Architecture: armel
Multi-Arch: same
Source: eglibc
Version: 2.13-33
Provides: libc-dev
Depends: libc6 (= 2.13-33), libc-dev-bin (= 2.13-33), linux-libc-dev
Recommends: gcc | c-compiler
Suggests: glibc-doc, manpages-dev
Breaks: binutils (<< 2.20.1-1), binutils-gold (<< 2.20.1-11), cmake (<< 2.8.4+dfsg.1-5), gcc-4.4 (<< 4.4.6-4), gcc-4.5 (<< 4.5.3-2), gcc-4.6 (<< 4.6.0-12), libhwloc-dev (<< 1.2-3), libjna-java (<< 3.2.7-4), liblouis-dev (<< 2.3.0-2), liblouisxml-dev (<< 2.4.0-2), make (<< 3.81-8.1), pkg-config (<< 0.26-1)
Conflicts: libc0.1-dev, libc0.3-dev, libc6.1-dev
Description: Embedded GNU C Library: Development Libraries and Header Files
Contains the symlinks, headers, and object files needed to compile
and link programs which use the standard C library.
Homepage: http://www.eglibc.org
`-

,--=[ /var/lib/dpkg/updates/0006
Package: libc6-dev
Status: unknown ok not-installed
Priority: optional
Section: libdevel
Architecture: armel
`-

/var/lib/dpkg/status includes:
,-
Package: libc6-dev
Status: install ok installed
Priority: optional
Section: libdevel
Installed-Size: 10558
Maintainer: GNU Libc Maintainers <debian-glibc@lists.debian.org>
Architecture: amd64
Multi-Arch: same
Source: eglibc
Version: 2.13-33
Provides: libc-dev
Depends: libc6 (= 2.13-33), libc-dev-bin (= 2.13-33), linux-libc-dev
Recommends: gcc | c-compiler
Suggests: glibc-doc, manpages-dev
Breaks: binutils (<< 2.20.1-1), binutils-gold (<< 2.20.1-11), cmake (<<
2.8.4+dfsg.1-5), gcc-4.4 (<< 4.4.6-4), gcc-4.5 (<< 4.5.3-2), gcc-4.6 (<<
4.6.0-12), libhwloc-dev (<< 1.2-3), libjna-java (<< 3.2.7-4), liblouis-dev
(<< 2.3.0-2), liblouisxml-dev (<< 2.4.0-2), make (<< 3.81-8.1), pkg-config
(<< 0.26-1)
Conflicts: libc0.1-dev, libc0.3-dev, libc6.1-dev
Description: Embedded GNU C Library: Development Libraries and Header Files
Contains the symlinks, headers, and object files needed to compile
and link programs which use the standard C library.
Homepage: http://www.eglibc.org

Package: libc6-dev
Status: deinstall ok installed
Priority: optional
Section: libdevel
Installed-Size: 8531
Maintainer: GNU Libc Maintainers <debian-glibc@lists.debian.org>
Architecture: armel
Multi-Arch: same
Source: eglibc
Version: 2.13-33
Provides: libc-dev
Depends: libc6 (= 2.13-33), libc-dev-bin (= 2.13-33), linux-libc-dev
Recommends: gcc | c-compiler
Suggests: glibc-doc, manpages-dev
Breaks: binutils (<< 2.20.1-1), binutils-gold (<< 2.20.1-11), cmake (<<
2.8.4+dfsg.1-5), gcc-4.4 (<< 4.4.6-4), gcc-4.5 (<< 4.5.3-2), gcc-4.6 (<<
4.6.0-12), libhwloc-dev (<< 1.2-3), libjna-java (<< 3.2.7-4), liblouis-dev
(<< 2.3.0-2), liblouisxml-dev (<< 2.4.0-2), make (<< 3.81-8.1), pkg-config
(<< 0.26-1)
Conflicts: libc0.1-dev, libc0.3-dev, libc6.1-dev
Description: Embedded GNU C Library: Development Libraries and Header Files
Contains the symlinks, headers, and object files needed to compile
and link programs which use the standard C library.
Homepage: http://www.eglibc.org
`-

After manually appending "Multi-Arch: same" to the file in dpkg/updates (for
libc6-dev:armel and for another package from the same run), dpkg let me proceed.
This suggests a fix: don't remove the field until possibly some time later.

(I have a btrfs snapshot of the system, in case more information is needed.)


Debian Release: wheezy/sid
APT prefers unstable
APT policy: (500, 'unstable'), (500, 'testing'), (150, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386
armel

Kernel: Linux 3.3.0-trunk-amd64 (SMP w/6 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash



To UNSUBSCRIBE, email to debian-bugs-dist-REQUEST@lists.debian.org
with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org