Comment 6 for bug 1764220

Verified 1.18.4ubuntu1.7 on Xenial:

root@x-zstd:~# wget https://people.canonical.com/~rbalint/zstd-debs/glibc-doc-reference_2.33-0ubuntu2~zstd1_all.deb
--2021-04-21 15:37:36-- https://people.canonical.com/~rbalint/zstd-debs/glibc-doc-reference_2.33-0ubuntu2~zstd1_all.deb
Resolving people.canonical.com (people.canonical.com)... 91.189.89.62
Connecting to people.canonical.com (people.canonical.com)|91.189.89.62|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 5618446 (5.4M) [application/x-debian-package]
Saving to: ‘glibc-doc-reference_2.33-0ubuntu2~zstd1_all.deb’

glibc-doc-reference_2.33-0ubuntu2~zstd1_all 100%[=========================================================================================>] 5.36M 4.76MB/s in 1.1s

2021-04-21 15:37:38 (4.76 MB/s) - ‘glibc-doc-reference_2.33-0ubuntu2~zstd1_all.deb’ saved [5618446/5618446]

root@x-zstd:~# dpkg-deb -R glibc-doc-reference_2.33-0ubuntu2~zstd1_all.deb glibc-doc-extracted
dpkg-deb: error: archive 'glibc-doc-reference_2.33-0ubuntu2~zstd1_all.deb' uses unknown compression for member 'control.tar.zst', giving up
root@x-zstd:~# sed -i s/backports/proposed/ /etc/apt/sources.list
root@x-zstd:~# apt update -qq
5 packages can be upgraded. Run 'apt list --upgradable' to see them.
root@x-zstd:~# apt install -qq dpkg
The following package was automatically installed and is no longer required:
  libfreetype6
Use 'apt autoremove' to remove it.
The following additional packages will be installed:
  libzstd1
The following NEW packages will be installed:
  libzstd1
The following packages will be upgraded:
  dpkg
1 upgraded, 1 newly installed, 0 to remove and 4 not upgraded.
Need to get 2,237 kB of archives.
After this operation, 399 kB of additional disk space will be used.
Do you want to continue? [Y/n]
Selecting previously unselected package libzstd1.
(Reading database ... 25816 files and directories currently installed.)
Preparing to unpack .../libzstd1_1.3.1+dfsg-1~ubuntu0.16.04.1_amd64.deb ...
Unpacking libzstd1 (1.3.1+dfsg-1~ubuntu0.16.04.1) ...
Processing triggers for libc-bin (2.23-0ubuntu11.2) ...
Setting up libzstd1 (1.3.1+dfsg-1~ubuntu0.16.04.1) ...
Processing triggers for libc-bin (2.23-0ubuntu11.2) ...
(Reading database ... 25821 files and directories currently installed.)
Preparing to unpack .../dpkg_1.18.4ubuntu1.7_amd64.deb ...
Unpacking dpkg (1.18.4ubuntu1.7) over (1.18.4ubuntu1.6) ...
Setting up dpkg (1.18.4ubuntu1.7) ...
Processing triggers for man-db (2.7.5-1) ...
root@x-zstd:~# time dpkg-deb -R glibc-doc-reference_2.33-0ubuntu2~zstd1_all.deb glibc-doc-extracted

real 0m0.031s
user 0m0.009s
sys 0m0.037s
root@x-zstd:~# dpkg -i glibc-doc-reference_2.33-0ubuntu2~zstd1_all.deb
Selecting previously unselected package glibc-doc-reference.
(Reading database ... 25821 files and directories currently installed.)
Preparing to unpack glibc-doc-reference_2.33-0ubuntu2~zstd1_all.deb ...
Unpacking glibc-doc-reference (2.33-0ubuntu2~zstd1) ...
Setting up glibc-doc-reference (2.33-0ubuntu2~zstd1) ...
Processing triggers for install-info (6.1.0.dfsg.1-5) ...
root@x-zstd:~# dpkg -l glibc-doc-reference
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-=====================================-=======================-=======================-================================================================================
ii glibc-doc-reference 2.33-0ubuntu2~zstd1 all GNU C Library: Documentation
root@x-zstd:~# sed -i 's/# deb-src/deb-src/' /etc/apt/sources.list
root@x-zstd:~# apt update -qq
4 packages can be upgraded. Run 'apt list --upgradable' to see them.
root@x-zstd:~# apt build-dep hello
Reading package lists... Done
Reading package lists... Done
...
Setting up libdpkg-perl (1.18.4ubuntu1.7) ...
Setting up dpkg-dev (1.18.4ubuntu1.7) ...
...
Processing triggers for libc-bin (2.23-0ubuntu11.2) ...
root@x-zstd:~# apt source hello
Reading package lists... Done
Need to get 733 kB of source archives.
Get:1 http://archive.ubuntu.com/ubuntu xenial/main hello 2.10-1 (dsc) [1,323 B]
...
'_apt'. - pkgAcquire::Run (13: Permission denied)
root@x-zstd:~# cd hello-2.10/
root@x-zstd:~/hello-2.10# dpkg-buildpackage
dpkg-buildpackage: source package hello
...
dpkg-deb: building package 'hello' in '../hello_2.10-1_amd64.deb'.
 dpkg-genchanges >../hello_2.10-1_amd64.changes
dpkg-genchanges: including full source code in upload
 dpkg-source --after-build hello-2.10
dpkg-buildpackage: full upload (original source is included)
root@x-zstd:~/hello-2.10# cd ..
root@x-zstd:~# rm -rf hello-2.10/

root@x-zstd:~# apt source hello
...
root@x-zstd:~# cd hello-2.10/
root@x-zstd:~/hello-2.10# vi debian/rules
root@x-zstd:~/hello-2.10# cat debian/rules
#!/usr/bin/make -f
%:
 dh $@

override_dh_auto_clean:
 [ ! -f Makefile ] || $(MAKE) distclean

override_dh_installdocs:
 dh_installdocs NEWS

override_dh_builddeb:
 dh_builddeb -- -Zzstd
root@x-zstd:~/hello-2.10# dpkg-buildpackage
dpkg-buildpackage: source package hello
...
dh_builddeb -- -Zzstd
dpkg-deb: error: only decompression is supported for 'zstd'!

Type dpkg-deb --help for help about manipulating *.deb files;
Type dpkg --help for help about installing and deinstalling packages.
dh_builddeb: dpkg-deb -Zzstd --build debian/hello .. returned exit code 2
debian/rules:12: recipe for target 'override_dh_builddeb' failed
make[1]: *** [override_dh_builddeb] Error 1
make[1]: Leaving directory '/root/hello-2.10'
debian/rules:3: recipe for target 'binary' failed
make: *** [binary] Error 2
dpkg-buildpackage: error: debian/rules binary gave error exit status 2
root@x-zstd:~/hello-2.10# dpkg -l dpkg dpkg-dev
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-=====================================-=======================-=======================-================================================================================
ii dpkg 1.18.4ubuntu1.7 amd64 Debian package management system
ii dpkg-dev 1.18.4ubuntu1.7 all Debian package development tools
root@x-zstd:~/hello-2.10#