sudo apt install build-essential
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 build-essential : Depends: libc6-dev but it is not going to be installed or
                            libc-dev
                   Depends: g++ (>= 4:9.2) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
rwinner@Clubuntu:~$ sudo apt install libc6-dev
[sudo] password for rwinner:
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 libc6-dev : Depends: libc6 (= 2.31-0ubuntu9) but 2.31-0ubuntu9.2 is to be installed
E: Unable to correct problems, you have held broken packages.
rwinner@Clubuntu:~$ sudo apt install libc6
Reading package lists... Done
Building dependency tree
Reading state information... Done
libc6 is already the newest version (2.31-0ubuntu9.2).
libc6 set to manually installed.
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
rwinner@Clubuntu:~$ sudo apt install libc-dev
Reading package lists... Done
Building dependency tree
Reading state information... Done
Note, selecting 'libc6-dev' instead of 'libc-dev'
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 libc6-dev : Depends: libc6 (= 2.31-0ubuntu9) but 2.31-0ubuntu9.2 is to be installed
E: Unable to correct problems, you have held broken packages.
rwinner@Clubuntu:~$ sudo apt install libc6\
> ^C
rwinner@Clubuntu:~$ sudo apt install libc6
Reading package lists... Done
Building dependency tree
Reading state information... Done
libc6 is already the newest version (2.31-0ubuntu9.2).
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
rwinner@Clubuntu:~$ sudo apt install libc-dev
Reading package lists... Done
Building dependency tree
Reading state information... Done
Note, selecting 'libc6-dev' instead of 'libc-dev'
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 libc6-dev : Depends: libc6 (= 2.31-0ubuntu9) but 2.31-0ubuntu9.2 is to be installed
E: Unable to correct problems, you have held broken packages.
rwinner@Clubuntu:~$ sudo apt install build-essential
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 build-essential : Depends: libc6-dev but it is not going to be installed or
                            libc-dev
                   Depends: g++ (>= 4:9.2) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
rwinner@Clubuntu:~$ sudo apt install g++
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 g++ : Depends: g++-9 (>= 9.3.0-3~) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.