jammy haskell-devscripts-minimal prevent launchpad builds of ghc pkgs

[Jens Elkner]

When trying to create new ghc packages for jammy on launchpad, haskell devscripts (/usr/share/cdbs/1/class/hlibrary.mk) fail with strange error messages like:

...
Running dh_haskell_depends -plibghc-hexpat-dev
ghc-pkg: cannot parse 'List-0.6.2-CBzPU1mwmz68Yae32Ju0Tg' as a package identifier (exact): "<eitherParsec>" (line 1, column 34):
unexpected all digits or a dot in a portion of package name
expecting "-"
make: *** [/usr/share/cdbs/1/class/hlibrary.mk:204: install/libghc-hexpat-dev] Error 1
dpkg-buildpackage: error: fakeroot debian/rules binary subprocess returned exit status 2
...

The error message seems is very strange, because package IDs are generated by haskell itself.

Same src package works since xenial, i.e. no probblems on xenial|bionic|focal.

For details see: https://launchpadlibrarian.net/618240334/buildlog_ubuntu-jammy-amd64.libghc-hexpat-dev-src_0.20.13-9.22.4_BUILDING.txt.gz

The related source packages are available via launchpad:
https://launchpad.net/~hets/+archive/ubuntu/hets?field.series_filter=jammy

E.g.:
libghc-list-src (required by hexpat)
  https://launchpad.net/~hets/+archive/ubuntu/hets/+sourcepub/13872690/+listing-archive-extra
libghc-hexpat-src
  https://launchpad.net/~hets/+archive/ubuntu/hets/+sourcepub/13872696/+listing-archive-extra

[Jens Elkner (jelmd)]

Found an easy way to identify the problem:

On focal:
---------
cd /tmp
wget https://launchpad.net/~hets/+archive/ubuntu/hets/+files/libghc-list-dev_0.6.2-4.20.4_amd64.deb
dpkg -i libghc-list-dev_0.6.2-4.20.4_amd64.deb
ghc-pkg --global field List-0.6.2-CBzPU1mwmz68Yae32Ju0Tg library-dirs

works.

On jammy:
---------
cd /tmp
wget https://launchpad.net/~hets/+archive/ubuntu/hets/+files/libghc-list-dev_0.6.2-5.22.4_amd64.deb
dpkg -i libghc-list-dev_0.6.2-5.22.4_amd64.deb
ghc-pkg --global field List-0.6.2-CBzPU1mwmz68Yae32Ju0Tg library-dirs

fails.

So it seems, that /usr/bin/dh_haskell_depends needs to be adjusted to remove the trailing -$ID when getting any field from a package.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Tillmo (till-mossakowski)]

A quick fix: in /usr/share/haskell-devscripts/Dh_Haskell.sh , remove the if statement (line 147)
  if dpkg --compare-versions "${ghcversion}" '>=' 8
and only keep the else branch
  dep=`strip-hash $2`
It seems that ghc-pkc 8.6.5 (used in focal) can handle unstripped package ids, but ghc-pkc 8.8.4 (used in jammy) cannot (and neither can ghc-pkc with version < 8).

[Jens Elkner (jelmd)]

Not sure, why ubuntu does not care about broken software, but it looks like we need to build our own haskell-devscripts-minimal package, since simply patching the buggy script during build is not possible.

Just in case the "un-maintainers" wake up, the patch below fixes the problem.

[Jens Elkner (jelmd)]

fix buggy /usr/share/haskell-devscripts/Dh_Haskell.sh

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "dh-hc-script.patch" seems to be a patch. If it isn't, please remove the "patch" flag from the attachment, remove the "patch" tag, and if you are a member of the ~ubuntu-reviewers, unsubscribe the team.

[This is an automated message performed by a Launchpad user owned by ~brian-murray, for any issues please contact him.]