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Version 11 (modified by Gedare Bloom, on 05/14/15 at 16:38:16) (diff)

Refactor notes on release terminology

Release Procedures

This page details the various stages, processes and procedures required to create a release of RTEMS. RTEMS is the RTEMS Realtime kernel, tools, tests and documentation.

The RTEMS Project is a volunteer effort and only maintains the current and one previous release. Users wishing to have older releases maintained should enquire about commercial support. The RTEMS Project attempts to provide access to previous releases as release.

Release Terminology

  • A release is the creation of any generated files and their packaging together with the source in a repository that makes the package available as a file.
  • A release branch is a git branch pushed to the repositories.
  • A release branch release is a git tag on a release branch with the tags pushed to the repositories.

Release Stages

The source code in the various git repositories will be in one of the following stages:

Stage Description
MASTER_OPEN The master branch in all repositories is open and new features and potentially unstable changes can be committed. Users should expect unstable behaviour.
MASTER_SLUSHY The repositories are closed to new features. Features existing in the master branch can be completed. Users should expect unstable behaviour.
MASTER_FROZEN The repositories are closed to all changes except bug fixes.
RELEASE_BRANCH A release branch is made in each repository once all the repositories pass the required release test requirements. The master branch returns to the MASTER_OPEN stage. All changes must have a ticket and commits must reference the ticket. A release branch is tagged with each release as it is created. The release branch remains open until it is archived.
RELEASE_ARCHIVED The release branch is archived. No further changes are made to the branch.

Stages changes on the master branch are announced on the devel@… mailing list. The decision to change is made by agreement of the core developers. There are no changes in the repositories to reflect this. The release page in the wiki will indicate the state.

Working on Releases

  • Features for a master branch should be listed as an enhancement ticket.
  • Only the current and previous release branches are active and all other release branches are archived.
  • An archived release branch cannot be changed.

RTEMS Release Repositories

The following repositories are part of an RTEMS release:

  1. RTEMS (git://
  2. RTEMS Source Builder (git://
  3. RTEMS Tools (git://
  4. RTEMS Testing Support (git://
  5. Example applications (git://
  6. Networking examples (git://
  • The release branches and tags must be consistent across these repositories.

RTEMS Release Numbering and Naming

The RTEMS Release Number and Naming relates to all repositories and packages released. The version number has three (3) numbers and the numbers are major.minor.release.

The major version number defines the release series. A release series up to RTEMS 4 has traditionally reflected changes in the user Application Programming Interface (API) and has been slow moving. RTEMS has shifted to support standards base interfaces for users and this means user API are stable and not changing. Therefore, RTEMS Series 5 and higher uses the major number to better reflect major feature changes in RTEMS.
The minor version number changes when a release branch is created.
The release version number changes for a release branch release, that is, when a release is created on that release branch. The first release version number is 0. This is sometimes called the dot release.

RTEMS Branch Labels

The RTEMS release branches are labelled by the major release number and minor release delimited with a period (.). For example the release branch label for RTEMS 4.11 is 4.11.

A development release is any code taken from the master branch of a repository.

RTEMS Release 4 Series Numbering

Release numbering for the Series 4 releases use the minor release dot number of .99 for development releases. For example the development release numbering for RTEMS 4.11 is 4.11.99. This allows testing of any version number related code, processes and procedures to happen with correct minor version number.

The release procedure requires the release's minor dot number to be set to '0' before the release branch is created and it is used for the first branch release. Further branch releases increment the minor release number when a branch release is made.

RTEMS Release 5 Series And Higher Numbering

Release numbering for Series 5 and higher releases use even minor release numbers as development releases and odd minor release numbers for releases. For example RTEMS 5.0 is a development release, that is any code taken from the master branch, and RTEMS 5.1 is an actual RTEMS release. The minor release dot number stays at 0 for all development releases.

The release procedure requires the release's minor number is incremented to the next odd number then the release branch is created. The release minor dot number is incremented when a new release branch release is made.

Source Checklist

The items in these lists are in no particular order and subject to discussion, additions, and deletions.

The following are things that MUST be resolved before a release is made

  • Tools stabilized on known versions, these can be different versions if required.
    • If it is not possible for a tool to be built it must be well documented in the release notes.
  • All BSPs must build without error

The following are things that WOULD BE NICE to be resolved before a release is branched

  • Warning reduction pass
    • Focus on all SPARC BSPs, select PowerPC, ARM and MIPS

Required BSPs and Conditions

These BSPs must build and have all tests without errors.

  • sparc/erc32
  • ...

Coverage reports for these BSPs

  • sparc/erc32

Release Checklist

Main release steps.



  1. Create branch for release


  1. Announcement


  1. Bump default version to the current release
  2. Generate 'next' milestone


  1. Upload file to FTP with sha256.


  1. Generate docs from branch.
    1. Texinfo
    2. Doxygen
    3. RSB
  2. Update

Tarball Generation

  1. Run bootstrap
  2. Generate ChangeLog using script found in #2208


There are no snapshots as of yet.