Bug#727786: removal of libc6-amd64 makes system unusable

[Paul Gevers <elbrus@debian.org>]

Package: eglibc
Version: 2.13-38
Severity: grave
Justification: leaves system unusable

[Sorry for not filing this bug with reportbug, but due to this bug that
doesn't work anymore. I am also unable to sign my mail at this moment,
due to this bug.]

For building an i386-only package I libc6-amd64 was installed on my
multiarch system. After removal of the package I got apt telling me:

The following packages were automatically installed and are no longer
required:
  libc6-amd64:i386 libc6-dev:i386 linux-libc-dev:i386
Use 'apt-get autoremove' to remove them.

So, I followed up with
paul@wollumbin ~ $ sudo apt-get autoremove
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be REMOVED:
  libc6-amd64:i386 libc6-dev:i386 linux-libc-dev:i386
0 upgraded, 0 newly installed, 3 to remove and 0 not upgraded.
After this operation, 31.5 MB disk space will be freed.
Do you want to continue [Y/n]?
(Reading database ... 227583 files and directories currently installed.)
Removing libc6-amd64 ...
dpkg (subprocess): unable to execute installed post-removal script
(/var/lib/dpkg/info/libc6-amd64.postrm): No such file or directory
dpkg: error processing libc6-amd64 (--remove):
 subprocess installed post-removal script returned error exit status 2
Removing libc6-dev:i386 ...
Removing linux-libc-dev:i386 ...
Errors were encountered while processing:
 libc6-amd64
E: Problem executing scripts DPkg::Post-Invoke '/usr/bin/test -e
/usr/share/dbus-1/system-services/org.freedesktop.PackageKit.service &&
/usr/bin/test -S /var/run/dbus/system_bus_socket && /usr/bin/gdbus call
--system --dest org.freedesktop.PackageKit --object-path
/org/freedesktop/PackageKit --timeout 1 --method
org.freedesktop.PackageKit.StateHasChanged cache-update > /dev/null;
/bin/echo > /dev/null'
E: Sub-process returned an error code
E: Sub-process /usr/bin/dpkg returned an error code (1)

Now, all my executables in /usr/bin and /bin are not usable:
paul@wollumbin ~ $ ll /usr/bin/
bash: /bin/ls: No such file or directory

I can still cd to /bin or /usr/bin, but the system complains that there
the files are not there. I hope I still can fix this... but at the
moment my possibilities are limited.