From Fedora Project Wiki
(Change approved by FESCo)
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* FESCo issue: [https://pagure.io/fesco/issue/2500 #2500]
 
* FESCo issue: [https://pagure.io/fesco/issue/2500 #2500]
* Tracker bug: <will be assigned by the Wrangler>
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* Tracker bug: [https://bugzilla.redhat.com/show_bug.cgi?id=1900006 #1900006]
* Release notes tracker: <will be assigned by the Wrangler>
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* Release notes tracker: <will not be assigned by the Wrangler - not user-facing>
  
 
== Detailed Description ==
 
== Detailed Description ==

Revision as of 15:17, 20 November 2020


Remove make from BuildRoot

Summary

This change will remove make from the default buildroot in Koji and mock.

Owner

Current status

  • Targeted release: Fedora 34
  • Last updated: 2020-11-20
  • FESCo issue: #2500
  • Tracker bug: #1900006
  • Release notes tracker: <will not be assigned by the Wrangler - not user-facing>

Detailed Description

Phase 1: Analysis

For this change, we will start by creating a list of all packages that have a build-time dependency on make. This will be done by analyzing spec files and also by rebuilding all packages in Fedora with make removed from the buildroot to see which packages fail to build. Once we have this list, we will remove packages that already have BuildRequires:make in their spec file, and this final list[1] will be all the packages that need to be updated in Phase 2.

[1] https://github.com/tstellar/fedora-change-make-buildroot/blob/main/needs_br_make.txt

Phase 2: Package Updates

Once we have the list of packages that need to be updated, we will proceed with adding BuildRequires: make to all spec files that require it. This new BuildRequires will be added to the line after the last BuildRequires in the spec file. The release number for packages will *not* be incremented for this change.

We will send an announcement to the devel list one week before the planned updates to give package maintainers a chance to update their packages manually if they want. After the week has passed, the spec files will be automatically updated and changes will be pushed directly to dist-git once they are ready.

During this phase, a conditional dependency on make will also be added to the redhat-rpm-config package. See explanation in the Feedback section for more details.

Phase 3: Update Buildroot

Once package spec files have been updated, then we can proceed with removing make from the BuildRoot. This will be done by removing make from the build group in Koji and by removing make from the buildsys-build group in comps (fedora-comps). In order to avoid issues with Koschei, this change will need to be made as close as possible to the start of the mass rebuild. If possible, we will try to first remove make from the mass rebuild side-tag and then remove it from rawhide after the rebuild completes.

Phase 4: Monitor Failures

Once all the changes are in place, we will continue to monitor koji builds to see if there are any failures related to this change. We expect that the analysis done in Phase 1 would give us the complete list of packages that need to be updated, but it is always possible that something will be missed.

Feedback

  • Removing make from the Buildroot without rebuilding the packages first has the potential to cause mass failures in Koschei. This is because Koschei builds from the latest SRPM and not from dist-git. We can minimize this problem by removing make from the buildroot as close as possible to the mass rebuild. The proposal has been updated now to account for this issue.
  • gcc relies on make in order to parallelize LTO builds. Therefore, removing make from the buildroot will cause build time regressions for packages that build with gcc but don not use make. To resolve this, we will add make as a conditional dependency to redhat-rpm-config:
  Requires: (make if gcc)

Benefit to Fedora

Based on my research[1], Fedora Rawhide has 22,309 packages, and there are approximately 10,378 packages that either use make explicitly or fail to build when make is removed form the buildroot. This means that there are around 11,931 packages that don't need make. Removing make from the BuildRoot will reduce the network traffic, download times, and disk usage for these builds in Koji and also for users doing builds with mock.

Removing make (and its dependencies) will:

  • Reduce the BuildRoot download size by: 7.3 MB [2]:
    • make: 539k
    • gc: 104k
    • guile22: 6.6M
    • libtool-ltdl: 36k
  • Reduce the BuildRoot install size by; 46 MB [2]:
    • make: 1.6M
    • gc: 229k
    • guile22: 44M
    • libtool-ltdl: 71k

[1] https://github.com/tstellar/fedora-change-make-buildroot

[2] Package sizes are from the x86_64 packages.


Scope

  • Proposal owners: Tom Stellard
  • Package Maintainers: Fedora package maintainers should report bugs if they think there is a problem caused by this change, but otherwise there will be no action required by them.
  • Proven Packager: The proposal owner will need to either apply for provenpackager status or get the help of someone with provenpackager status in order to make the spec file changes that are required.
  • Release engineering: #9829 (a check of an impact with Release Engineering is needed)
  • Policies and guidelines: The packager guidelines will need to be updated to mention that BuildRequires: make is now required for all packages that need make.
  • Trademark approval: N/A (not needed for this Change)
  • Alignment with Objectives: This aligns with the Fedora Minimization objective.

Upgrade/compatibility impact

This should not impact upgrades.

How To Test

This change can be tested by rebuilding affected packages. The goal is to complete this before the mass rebuild to ensure maximum testing coverage.

User Experience

Fedora users will not notice any difference with this change. This will only impact Fedora package maintainers.

Dependencies

gcc < 11 will fail if the -flto=auto option is used when make is not installed. Phase 3 cannot be completed until gcc 11 lands in rawhide, but Phase 1 and Phase 2 are not blocked by this.

Contingency Plan

  • Contingency mechanism: If we discover critical issues during phase 4, then Fedora Release Engineering will need to re-add make into the buildroot.
  • Contingency deadline: 2021-02-23 (F34 Beta Freeze)
  • Blocks release? No
  • Blocks product? No

Documentation

The packager guidelines will need to be updated to mention that BuildRequires: make is now required for all packages that need make.

Release Notes