cannot 'apt upgrade' after install of 16.04.1

[Guest]

On making a fresh install of 16.04.1, I ran the commands for

[FONT=courier new]sudo apt update
sudo apt upgrade[/FONT]

and I get the error as:

[FONT=courier new]Preparing to unpack .../libc6_2.23-0ubuntu5_amd64.deb ...

LD_LIBRARY_PATH contains the traditional /lib directory,
but not the multiarch directory /lib/x86_64-linux-gnu.
It is not safe to upgrade the C library in this situation;
please remove the /lib/directory from LD_LIBRARY_PATH and
try again.

dpkg: error processing archive /var/cache/apt/archives/libc6_2.23-0ubuntu5_amd64.deb (--unpack):
subprocess new pre-installation script returned error exit status 1
Processing triggers for libc-bin (2.23-0ubuntu5) ...
Errors were encountered while processing:
/var/cache/apt/archives/libc6_2.23-0ubuntu5_amd64.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
kenzo@kenzo-Latitude-3460:~$
[/FONT]

I checked the

LD_LIBRARY_PATH

and this is the output:

kenzo@kenzo-Latitude-3460:~$ echo $LD_LIBRARY_PATH

kenzo@kenzo-Latitude-3460:~$

[Guest]

Solved.

I installed the other packages apart from libc which came in the list of upgradeable packages, rebooted my computer and it worked fine.

The problem could be replicated by reinstalling a fresh copy of kubuntu 16.04.1 and running apt update and apt upgrade. The three packages libc-dev, libc-dbg and libc upgrades itself, but falls into a loop of dependence issues as the libc-dev depends on the latest version of libc. Unfortunately, the latter doesn't get installed first. I removed the libc-dev and libc-dbg using the command:

sudo dpkg --purge --force-depends "libc6-dev"
sudo dpkg --purge --force-depends "libc6-dbg"

I could then install 'libc-bin', on which 'libc' depends on.

and then was able to run 'apt -f install' without errors. Although I still couldn't run the 'apt upgrade'. I then installed the individual packages listed to upgrade, explicitly removing libc from the list. After this, I rebooted and then I didn't get the error anymore.

[Snowhog]

IF using apt (as opposed to apt-get), do yourself a huge favor and stop using apt upgrade; use apt full-upgrade instead. Your system will remain much more stable, as the full-upgrade option handles package dependencies intelligently, adding or removing packages as required to keep your system fully up to date; the upgrade option doesn't, and can leave your system in a broken state.

Open a konsole and type man apt and read all about it.