It seems that you have blindly applied non-universal commits from Debian:
https://git.launchpad.net/ubuntu/+source/bash-completion/log/completions/_umount https://git.launchpad.net/ubuntu/+source/bash-completion/log/completions/_umount.linux
while they are not compatible with `mawk`.
The `mawk` itself has the same version 1.3.3-17ubuntu3 on 18.04 LTS, 19.04 and 19.10 (see https://packages.ubuntu.com/search?suite=all&exact=1&searchon=names&keywords=mawk ). So it is not the problem.
So you should change `mawk` dependency to `gawk` on the Ubuntu side or revert these commits inside `bash-completion`.
It seems that you have blindly applied non-universal commits from Debian:
https:/ /git.launchpad. net/ubuntu/ +source/ bash-completion /log/completion s/_umount /git.launchpad. net/ubuntu/ +source/ bash-completion /log/completion s/_umount. linux
https:/
while they are not compatible with `mawk`.
The `mawk` itself has the same version 1.3.3-17ubuntu3 on 18.04 LTS, 19.04 and 19.10 (see https:/ /packages. ubuntu. com/search? suite=all& exact=1& searchon= names&keywords= mawk ). So it is not the problem.
So you should change `mawk` dependency to `gawk` on the Ubuntu side or revert these commits inside `bash-completion`.