FYI.

* debhelperの互換性レベル11が指定されたパッケージで * initスクリプトやsystemdサービスを含む　場合、 * "apt install X && apt remove X && apt install X" として2度同じパッケージを 　入れると、サービスが意図に反して自動起動しない

というバグがありました。一度自分のパッケージを見直してみると良いと思います。

あと * 互換性レベル9が廃止になります 　なので、とっとと debhelper への依存は Build-Depends: debhelper-compat (= 12) 　に置き換えて debian/compat ファイルを窓から放り投げましょう。

Begin forwarded message:

Date: Sat, 1 Feb 2020 15:38:14 +0100 From: Niels Thykier niels@thykier.net To: debian-devel-announce@lists.debian.org Subject: News about the debhelper toolchain

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We would like to share the following news about the debhelper toolchain with you! :)

Overview of this rather long email:

* Making Debian packaging more DRY and declarative * Highlights of current changes in compat 13 * Use of compat 11 is actively discouraged * Removals and deprecations of features and compat levels * Overview of which features are available in a given suite/backports

# Making Debian packaging more DRY and declarative

Over the past few Debian releases, we have implemented small steps towards supporting more declarative and DRY packaging paradigms. Some notably steps include (in no particular order):

* The "debhelper-compat (= 12)" build-dependency to replace "Build-Depends: debhelper (>= 12~)" and "echo 12 > debian/compat".

* The "dh-sequence-<foo> build-dependency" to replace the "--with <foo>" parameter to dh in the debian/rules. - Note that third-party add-ons may not have added the relevant Provides to support this change.

* Support for making "dh-sequence-<foo>" conditional by moving it to Build-Depends-Indep, or by adding an architecture restriction or by adding a build-profile requirement. This makes it easier for you to support porters and cross-builders in reducing the build-dependency requirements of your package. (#836699) - A small number of add-ons are not compatible with this feature. In general, dh(1) will detect this and abort when an error when it is detected.

* Support for new execute_before_X and execute_after_X targets. These are similar to regular override targets but are injected before and after the command X without affecting how X itself is called. This avoids having to repeat X in an override target when all you wanted was to run another command before or after X. - This feature is only enabled for compat 10 or later due to the complexity involved in supporting this for compat 9 and earlier.

* In compat 13, the dh command sequencer will skip any hook or override target for dh_auto_test, dh_dwz, and dh_strip if nocheck and nostrip are present in DEB_BUILD_OPTIONS. This avoids a papercut where overriding the commands often breaks the nocheck / nostrip functionality (unless you remember to inject the correct makefile runes).

Note that most of these changes requires recent versions of debhelper. Please see the final section of this mail for guidance on whether you can use them if you want to support older releases of Debian with the same packaging.

# Highlights of current changes in compat 13

Here is a brief list of a *subset* of the current changes planned for the future compat 13.

* dh_missing now defaults to --fail-missing.

* debhelper generate a temporary writable directory for $HOME and $XDG_RUNTIME_DIR plus clear all remaining XDG_* variables. This simplifies packaging of tools that insist on writing to $HOME.

* dh_install (and other helpers) will in compat 13 support basic substitution variables enabling you to reference paths containing spaces or dynamic values such as DEB_HOST_MULTIARCH. - Note this is *not* intended as a complete replacement of dh-exec(1).

* The dh command sequencer will in compat 13 skip any hook or override target for dh_auto_test, dh_dwz, and dh_strip if nocheck and nostrip are present in DEB_BUILD_OPTIONS. This avoids a papercut where overriding the commands often breaks the nocheck / nostrip functionality (unless you remember to inject the correct make runes).

* The dh_* commands no longer accepts arbitrary abbreviations of their command line arguments. This enables dh(1) to optimize the sequence better as it can now reliably detect which commands react to the given command line arguments.

Compat 13 is still open for changes and suggestion. If you have any requests or suggestions, feel free to submit them via a bug in the BTS or a MR request on salsa. You are also very welcome to test compat 13 and file bugs if you discover anything not working as advertised. Though please be aware of future changes to debhelper if you upload any packages to unstable that relies on compat 13.

# Use of compat 11 is actively discouraged

While it is possible to use compat 11 without triggering this issue, we have discouraged it as compat 11 has an unsafe and buggy default handling in service handling.

While this is the first time a compat have been discouraged (before being deprecated), please remember that a working package with this bug is better than a broken package!

We have identified an unfortunate issue in compat 11 related to how debhelper handles init.d and systemd services. A known problem is that "apt install X && apt remove X && apt install X" will cause services to not be started automatically on the second install, requiring the admin to start it manually.

This issue only manifests in compat 11 and only for packages with init.d / systemd services. Unfortunately, retroactively fixing compat 11 will be non-trivial and error-prone as it involves interaction between multiple helpers and how/whether options for a given helper affect init.d or/and systemd based services.

The general recommendation solution for packages is:

* Move forward to compat 12 unless you need to support Debian stretch. (Remember to check upgrade check list in "man debhelper" *and test* the compat bump)

If you need to support Debian stretch or cannot upgrade to compat 12 for other reasons, please consider the following options:

* If the package do not ship *any* init.d or systemd services, then you /can/ choose to stay with compat 11 without being affected.

- This is the rule of thumb for whether your package is affected. There may be exceptions that cannot fit in this mail (if in doubt, test the "install, remove, install" cycle and see if the service is in the correct state).

* Roll back to compat 10 globally in your package. (This is the "simple" choice but assumes you are not requiring a compat 11 feature)

* Override dh_installsystemd to remove it from the sequence and override dh_installinit to run dh_systemd_enable, dh_installinit and dh_systemd_start (in that order!). All three helpers must be run with DH_COMPAT=10 as an environment variable (e.g. "DH_COMPAT=10 dh_installinit") to make them use compat 10 instead of the default. (This is the "advanced" option; use only if you think it is worth the work).

* There may also be cases where staying with compat 11 and accepting the bug is the lesser evil.

As mentioned; please remember to test your migration away from compat 11 or your work around. This issue caused by compat 11 is nothing compared to the disruption caused by a frenzy of inadequately tested uploads to unstable.

# Removals and deprecations of features and compat levels

To keep the codebase manageable while continuing to improve debhelper, we periodically deprecate and remove obsolete features and workflow. This brings us to the following deprecations and removals.

* Removal of manual sequence control arguments for dh (--before/--after/--until/--remaining). This has already been implemented in debhelper/12.4 and facilitated the refactoring needed to implement the following improvements: - Conditional debhelper add-ons. - The new hook targets (execute_before_X and execute_after_X) - Support for skipping override/hook targets under nostrip/nocheck

* dh_gconf will be removed soon as it is no longer useful and (almost) everything has stopped using it. Please see #908845 for more details.

* The now unused --ignore option has been removed. It had a very narrow use-case in preset day and all packages have migrated away from using it now.

* Compatibility level 9 is hereby officially deprecated and will trigger deprecation warnings soon. We recommend people migrate their packages to compat 12 or 10 depending on whether oldstable support is needed. Please note that compat 11 is actively discouraged in some cases. (see the section above).

# Overview of which features are available in a given suite/backports

The debhelper toolchain is continuously seeing improvements. Among other to better defaults, less micromanagement, and better performance. Where reasonably possible, we attempt to make these changes available transparently. However, there are many cases where people cannot immediately rely on these improvements because they are targeting releases/distributions where debhelper does not yet have these features.

The following is an incomplete list of features now available by Debian release/suite, which we hope you will find useful in order to make your packaging simpler.

## If you target to stretch

If your target is vanilla oldstable (stretch), you can now assume features available in debhelper/10.2.5:

* compat 10

* dh_installchangelogs finds more changelog files by default.

* automatic dbgsym packages are universally available.

* dh_clean supports removal of directories listed in d/clean (when explicitly marked as a directory)

* debhelper now uses debian/.debhelper for (new) internal state, which makes it easier to manage .gitignore files.

* Improved cross-building support for cmake-based packages.

## If you target buster or/and stretch-backports

If your target is vanilla stable (buster) or oldstable-backports (stretch-backports), you can now assume features available in debhelper/12.1.1:

* compat 12 - dh_makeshlibs -V is default meaning less micro-management for udeb library packages. - dh_installinitramfs + dh_installsystemduser run by default - More reliable detection of ELF files (dh_strip + dh_shlibdeps)

* meson (+ninja) and cmake+ninja build system

* The ability to use debhelper-compat (= X) and dh-sequence-X in Build-Depends to declare debhelper compat level and used dh addons. - Note: dh-sequence-X cannot be used conditionally in buster nor stretch-backports. This requires buster-backports or bullseye.

* Derivatives or custom build processes can use DH_EXTRA_ADDONS environment variables to inject global specific addons in all packages relying on dh.

* dh_installsystemduser is available.

* dh_installchangelogs automatically detects and uses upstream installed changelog (avoids duplicated changelog warning from lintian in single binary source packages)

* Cross-building for QT5 working out of the box in many cases - This item is buster-only as there are some changes on the QT5 side for this to work.

## If you target bullseye or/and buster-backports

If you have no particular backwards compat support targets or are targeting stable-backports (buster-backports), you can assume the latest features available in debhelper (12.9):

* dh_installdeb can substitute more variables into your maintscripts for you - both built-in values and custom ones (the latter via -D). Please see dh_installdeb(1), section "SUBSTITUTION IN MAINTAINER SCRIPTS" and the description of -D/--define parameter, for more information. - This requires debhelper (>= 12.2~).

* dh_makeshlibs can often automatically detect udebs and generate shlibs without needing an explicit --add-udeb.

- Please test before blindly dropping an --add-udeb to avoid unnecessary breakage for the d-i team!

- Please add a Build-Dependency on debhelper (>= 12.6~) to avoid some bugs in the early implementations.

* dh now support conditional addons via build-dependencies to simplify bootstrapping and cross-building. - This requires debhelper (>= 12.7.2~) to work.

* dh now supports execute_before_X and execute_after_X targets in addition to override_X targets. - This feature requires debhelper (>= 12.8~) to work AND compat 10 or later.

* The debhelper tool suite now have basic support for cross-building Perl XS modules (provided the Build-Depends on perl-xs-dev) - Assume this is bullseye-only as there has (and is) ongoing work on the Perl side.