Unmet dependencies. Libc6 The package system is broken
I had similar issue on freshly installed Ubuntu 20.04.2 desktop 64bit, the difference is that libc6 ...9.3 was installed but my packages (g++ build-essential etc) could not be installed beceause libc6-dev could not be installed because it required libc6 ...9.2 which was older then the one installed
libc6-dev : Depends: libc6 (= 2.31-0ubuntu9.2) but 2.31-0ubuntu9.3 is to be installed
So I just downgraded libc6 (and libc-bin too, because it seems very related to me) to version 2.31-0ubuntu9.2 this way:
sudo apt install libc6=2.31-0ubuntu9.2 libc-bin=2.31-0ubuntu9.2
Now my packages could install :) so it seems to work, let's see if we don't have much problems - but I guess not because this is a tiny change in libc (on the other side libc is very important)
BUT I DON'T KNOW WHAT WILL HAPPEN IN THE FUTURE:
- Will it in future updates hold this package fixed to still old version?
- Does anyone know how to unfix this version?
- Even if I could somehow unfix it from this version, then will ubuntu have this issue in the future?
- Does anyone know if it is some bug in Ubuntu packaging repository? I repeat: this was on a totally fresh Ubuntu 20.04 desktop
Some other places to look for inspiration:
- https://serverfault.com/a/993629/445123
- https://serverfault.com/a/1005063/445123
I would like to add to the answer of Tomeg, that downgrading with aptitude helped me to keep my packages depending on libc6 installed. When downgrading with:
sudo apt install libc6=2.31-0ubuntu9.
apt would also uninstall all my packages depending on libc6.
The following packages will be DOWNGRADED:
libc6
0 upgraded, 0 newly installed, 1 downgraded, 206 to remove and 0 not upgraded.
As I described here this did help since aptitude offered me different options:
sudo aptitude install libc6=2.31-0ubuntu9.2
I had to decline the first two options (2x n) and then the third was to solely downgrade (y) without uninstalling other packages.