Fresh install of aptitude is broken - missing dependency?

[NeilGreenwood]

$ sudo apt install aptitude
Reading package lists... Done
Building dependency tree
Reading state information... Done
aptitude is already the newest version (0.8.10-6ubuntu1).
0 to upgrade, 0 to newly install, 0 to remove and 0 not to upgrade.
$ aptitude
aptitude: error while loading shared libraries: libsigc-2.0.so.0: cannot open shared object file: No such file or directory
$

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: aptitude 0.8.10-6ubuntu1
ProcVersionSignature: Ubuntu 5.0.0-32.34~18.04.2-generic 5.0.21
Uname: Linux 5.0.0-32-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.9
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Sat Nov 9 11:06:09 2019
EcryptfsInUse: Yes
SourcePackage: aptitude
UpgradeStatus: No upgrade log present (probably fresh install)

[NeilGreenwood (neil-greenwood)]

sudo apt install --reinstall libsigc++-2.0-0v5

this fixed it. Not a problem with aptitude. It seems I have a couple of problems with installed library packages after a fresh install.

[Axel Beckert (xtaran)]

I'm sorry, but I can't reproduce this issue in a clean 18.04 chroot:

aptitude is installed at version 0.8.10-6ubuntu1, too, and has a dependency on libsigc++-2.0-0v5 (version 2.10.0-2 installed as in your case) which contains /usr/lib/x86_64-linux-gnu/libsigc-2.0.so.0.

And aptitude works for me.

Can you run "dpkg -C libsigc++-2.0-0v5" to check if all files of that package are there and undamaged?

[NeilGreenwood (neil-greenwood)]

That was indeed the problem, which is why i marked this bug as invalid.

libsigc++-2.0-0v5 was damaged, along with some other library packages.

[Axel Beckert (xtaran)]

Hi,

NeilGreenwood wrote:
> That was indeed the problem, which is why i marked this bug as invalid.

Yeah, sorry, your second mail and my question crossed each other. I
only read your second mail after I'd sent my mail.

That's also why I corrected the state afterwards.

  Regards, Axel
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