docs/HowToReleaseLLVM.rst - llvm-project/llvm - Git at Google

 =================================
 How To Release LLVM To The Public
 =================================

 Introduction
 ============

 This document contains information about successfully releasing LLVM ---
 including sub-projects: e.g., ``clang`` and ``compiler-rt`` --- to the public.
 It is the Release Manager's responsibility to ensure that a high quality build
 of LLVM is released.

 If you're looking for the document on how to test the release candidates and
 create the binary packages, please refer to the :doc:`ReleaseProcess` instead.

 .. _timeline:

 Release Timeline
 ================

 LLVM is released on a time based schedule --- with major releases roughly
 every 6 months.  In between major releases there may be dot releases.
 The release manager will determine if and when to make a dot release based
 on feedback from the community.  Typically, dot releases should be made if
 there are large number of bug-fixes in the stable branch or a critical bug
 has been discovered that affects a large number of users.

 Unless otherwise stated, dot releases will follow the same procedure as
 major releases.

 The release process is roughly as follows:

 * Set code freeze and branch creation date for 6 months after last code freeze
   date.  Announce release schedule to the LLVM community and update the website.

 * Create release branch and begin release process.

 * Send out release candidate sources for first round of testing.  Testing lasts
   7-10 days.  During the first round of testing, any regressions found should be
   fixed.  Patches are merged from mainline into the release branch.  Also, all
   features need to be completed during this time.  Any features not completed at
   the end of the first round of testing will be removed or disabled for the
   release.

 * Generate and send out the second release candidate sources.  Only *critical*
   bugs found during this testing phase will be fixed.  Any bugs introduced by
   merged patches will be fixed.  If so a third round of testing is needed.

 * The release notes are updated.

 * Finally, release!

 * Announce bug fix release schedule to the LLVM community and update the website.

 * Tag bug fix -rc1 after 4 weeks have passed.

 * Tag bug fix -rc2 4 weeks after -rc1.

 * Tag additional -rc candidates, if needed, to fix critical issues in
   previous -rc releases.

 * Tag final release.

 Release Process
 ===============

 .. contents::
    :local:

 Release Administrative Tasks
 ----------------------------

 This section describes a few administrative tasks that need to be done for the
 release process to begin.  Specifically, it involves:

 * Updating version numbers,

 * Creating the release branch, and

 * Tagging release candidates for the release team to begin testing.

 Create Release Branch
 ^^^^^^^^^^^^^^^^^^^^^

 Branch the Git trunk using the following procedure:

 #. Remind developers that the release branching is imminent and to refrain from
    committing patches that might break the build.  E.g., new features, large
    patches for works in progress, an overhaul of the type system, an exciting
    new TableGen feature, etc.

 #. Verify that the current git trunk is in decent shape by
    examining nightly tester and buildbot results.

 #. Bump the version in trunk to N.0.0git and tag the commit with llvmorg-N-init.
    If ``X`` is the version to be released, then ``N`` is ``X + 1``.

 ::

   $ git tag -a llvmorg-N-init

 #. Clear the release notes in trunk.

 #. Create the release branch from the last known good revision from before the
    version bump.  The branch's name is release/X.x where ``X`` is the major version
    number and ``x`` is just the letter ``x``.

 #. All tags and branches need to be created in both the llvm/llvm-project and
    llvm/llvm-test-suite repos.

 Update LLVM Version
 ^^^^^^^^^^^^^^^^^^^

 After creating the LLVM release branch, update the release branches'
 ``CMakeLists.txt`` versions from '``X.0.0git``' to '``X.0.0``'.

 In addition, the version numbers of all the Bugzilla components must be updated
 for the next release.

 Tagging the LLVM Release Candidates
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

 Tag release candidates:

 ::

   $ git tag -a llvmorg-X.Y.Z-rcN

 The Release Manager must supply pre-packaged source tarballs for users.  This can
 be done with the export.sh script in utils/release.

 Tarballs, release binaries,  or any other release artifacts must be uploaded to
 GitHub.  This can be done using the github-upload-release.py script in utils/release.

 ::

   $ github-upload-release.py upload --token <github-token> --release X.Y.Z-rcN --files <release_files>

 ::

   $ ./export.sh -release X.Y.Z -rc $RC

 This will generate source tarballs for each LLVM project being validated, which
 can be uploaded to github for further testing.

 Build The Binary Distribution
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

 Creating the binary distribution requires following the instructions
 :doc:`here <ReleaseProcess>`.

 That process will perform both Release+Asserts and Release builds but only
 pack the Release build for upload. You should use the Release+Asserts sysroot,
 normally under ``final/Phase3/Release+Asserts/llvmCore-3.8.1-RCn.install/``,
 for test-suite and run-time benchmarks, to make sure nothing serious has
 passed through the net. For compile-time benchmarks, use the Release version.

 The minimum required version of the tools you'll need are :doc:`here <GettingStarted>`

 Release Qualification Criteria
 ------------------------------

 There are no official release qualification criteria.  It is up to the
 the release manager to determine when a release is ready.  The release manager
 should pay attention to the results of community testing, the number of outstanding
 bugs, and then number of regressions when determining whether or not to make a
 release.

 The community values time based releases, so releases should not be delayed for
 too long unless there are critical issues remaining.  In most cases, the only
 kind of bugs that are critical enough to block a release would be a major regression
 from a previous release.

 Official Testing
 ----------------

 A few developers in the community have dedicated time to validate the release
 candidates and volunteered to be the official release testers for each
 architecture.

 These will be the ones testing, generating and uploading the official binaries
 to the server, and will be the minimum tests *necessary* for the release to
 proceed.

 This will obviously not cover all OSs and distributions, so additional community
 validation is important. However, if community input is not reached before the
 release is out, all bugs reported will have to go on the next stable release.

 The official release managers are:

 * Major releases (X.0): Hans Wennborg
 * Stable releases (X.n): Tom Stellard

 The official release testers are volunteered from the community and have
 consistently validated and released binaries for their targets/OSs. To contact
 them, you should email the ``release-testers@lists.llvm.org`` mailing list.

 The official testers list is in the file ``RELEASE_TESTERS.TXT``, in the ``LLVM``
 repository.

 Community Testing
 -----------------

 Once all testing has been completed and appropriate bugs filed, the release
 candidate tarballs are put on the website and the LLVM community is notified.

 We ask that all LLVM developers test the release in any the following ways:

 #. Download ``llvm-X.Y``, ``llvm-test-X.Y``, and the appropriate ``clang``
    binary.  Build LLVM.  Run ``make check`` and the full LLVM test suite (``make
    TEST=nightly report``).

 #. Download ``llvm-X.Y``, ``llvm-test-X.Y``, and the ``clang`` sources.  Compile
    everything.  Run ``make check`` and the full LLVM test suite (``make
    TEST=nightly report``).

 #. Download ``llvm-X.Y``, ``llvm-test-X.Y``, and the appropriate ``clang``
    binary. Build whole programs with it (ex. Chromium, Firefox, Apache) for
    your platform.

 #. Download ``llvm-X.Y``, ``llvm-test-X.Y``, and the appropriate ``clang``
    binary. Build *your* programs with it and check for conformance and
    performance regressions.

 #. Run the :doc:`release process <ReleaseProcess>`, if your platform is
    *different* than that which is officially supported, and report back errors
    only if they were not reported by the official release tester for that
    architecture.

 We also ask that the OS distribution release managers test their packages with
 the first candidate of every release, and report any *new* errors in Bugzilla.
 If the bug can be reproduced with an unpatched upstream version of the release
 candidate (as opposed to the distribution's own build), the priority should be
 release blocker.

 During the first round of testing, all regressions must be fixed before the
 second release candidate is tagged.

 In the subsequent stages, the testing is only to ensure that bug
 fixes previously merged in have not created new major problems. *This is not
 the time to solve additional and unrelated bugs!* If no patches are merged in,
 the release is determined to be ready and the release manager may move onto the
 next stage.

 Reporting Regressions
 ---------------------

 Every regression that is found during the tests (as per the criteria above),
 should be filled in a bug in Bugzilla with the priority *release blocker* and
 blocking a specific release.

 To help manage all the bugs reported and which ones are blockers or not, a new
 "[meta]" bug should be created and all regressions *blocking* that Meta. Once
 all blockers are done, the Meta can be closed.

 If a bug can't be reproduced, or stops being a blocker, it should be removed
 from the Meta and its priority decreased to *normal*. Debugging can continue,
 but on trunk.

 Merge Requests
 --------------

 You can use any of the following methods to request that a revision from trunk
 be merged into a release branch:

 #. Use the ``utils/release/merge-request.sh`` script which will automatically
    file a bug_ requesting that the patch be merged. e.g. To request revision
    12345 be merged into the branch for the 5.0.1 release:
    ``llvm.src/utils/release/merge-request.sh -stable-version 5.0 -r 12345 -user bugzilla@example.com``

 #. Manually file a bug_ with the subject: "Merge r12345 into the X.Y branch",
    enter the commit(s) that you want merged in the "Fixed by Commit(s)" and mark
    it as a blocker of the current release bug.  Release bugs are given aliases
    in the form of release-x.y.z, so to mark a bug as a blocker for the 5.0.1
    release, just enter release-5.0.1 in the "Blocks" field.

 #. Reply to the commit email on llvm-commits for the revision to merge and cc
    the release manager.

 .. _bug: https://bugs.llvm.org/

 Release Patch Rules
 -------------------

 Below are the rules regarding patching the release branch:

 #. Patches applied to the release branch may only be applied by the release
    manager, the official release testers or the code owners with approval from
    the release manager.

 #. Release managers are encouraged, but not required, to get approval from code
    owners before approving patches.  If there is no code owner or the code owner
    is unreachable then release managers can ask approval from patch reviewers or
    other developers active in that area.

 #. *Before RC1* Patches should be limited to bug fixes, important optimization
    improvements, or completion of features that were started before the branch
    was created.  As with all phases, release managers and code owners can reject
    patches that are deemed too invasive.

 #. *Before RC2* Patches should be limited to bug fixes or backend specific
    improvements that are determined to be very safe.

 #. *Before RC3/Final Major Release* Patches should be limited to critical
    bugs or regressions.

 #. *Bug fix releases* Patches should be limited to bug fixes or very safe
    and critical performance improvements.  Patches must maintain both API and
    ABI compatibility with the previous major release.


 Merging Patches
 ^^^^^^^^^^^^^^^

 Use the ``git cherry-pick -x`` command to merge patches to the release branch:

 #. ``git cherry-pick -x abcdef0``

 #. Run regression tests.

 Release Final Tasks
 -------------------

 The final stages of the release process involves tagging the "final" release
 branch, updating documentation that refers to the release, and updating the
 demo page.

 Update Documentation
 ^^^^^^^^^^^^^^^^^^^^

 Review the documentation in the release branch and ensure that it is up
 to date.  The "Release Notes" must be updated to reflect new features, bug
 fixes, new known issues, and changes in the list of supported platforms.
 The "Getting Started Guide" should be updated to reflect the new release
 version number tag available from Subversion and changes in basic system
 requirements.

 .. _tag:

 Tag the LLVM Final Release
 ^^^^^^^^^^^^^^^^^^^^^^^^^^

 Tag the final release sources:

 ::

   $ git tag -a llvmorg-X.Y.Z
   $ git push https://github.com/llvm/llvm-project.git llvmorg-X.Y.Z

 Update the LLVM Website
 ^^^^^^^^^^^^^^^^^^^^^^^

 The website must be updated before the release announcement is sent out.  Here
 is what to do:

 #. Check out the ``www-releases`` module from GitHub.

 #. Create a new sub-directory ``X.Y.Z`` in the releases directory.

 #. Copy and commit the ``llvm/docs`` and ``LICENSE.txt`` files into this new
    directory.

 #. Update the ``releases/download.html`` file with links to the release
    binaries on GitHub.

 #. Update the ``releases/index.html`` with the new release and link to release
    documentation.

 #. Finally checkout the llvm-www repo and update the main page
    (``index.html`` and sidebar) to point to the new release and release
    announcement.

 Announce the Release
 ^^^^^^^^^^^^^^^^^^^^

 Send an email to the list announcing the release, pointing people to all the
 relevant documentation, download pages and bugs fixed.
	=================================
	How To Release LLVM To The Public
	=================================

	Introduction
	============

	This document contains information about successfully releasing LLVM ---
	including sub-projects: e.g., ``clang`` and ``compiler-rt`` --- to the public.
	It is the Release Manager's responsibility to ensure that a high quality build
	of LLVM is released.

	If you're looking for the document on how to test the release candidates and
	create the binary packages, please refer to the :doc:`ReleaseProcess` instead.

	.. _timeline:

	Release Timeline
	================

	LLVM is released on a time based schedule --- with major releases roughly
	every 6 months. In between major releases there may be dot releases.
	The release manager will determine if and when to make a dot release based
	on feedback from the community. Typically, dot releases should be made if
	there are large number of bug-fixes in the stable branch or a critical bug
	has been discovered that affects a large number of users.

	Unless otherwise stated, dot releases will follow the same procedure as
	major releases.

	The release process is roughly as follows:

	* Set code freeze and branch creation date for 6 months after last code freeze
	date. Announce release schedule to the LLVM community and update the website.

	* Create release branch and begin release process.

	* Send out release candidate sources for first round of testing. Testing lasts
	7-10 days. During the first round of testing, any regressions found should be
	fixed. Patches are merged from mainline into the release branch. Also, all
	features need to be completed during this time. Any features not completed at
	the end of the first round of testing will be removed or disabled for the
	release.

	* Generate and send out the second release candidate sources. Only critical
	bugs found during this testing phase will be fixed. Any bugs introduced by
	merged patches will be fixed. If so a third round of testing is needed.

	* The release notes are updated.

	* Finally, release!

	* Announce bug fix release schedule to the LLVM community and update the website.

	* Tag bug fix -rc1 after 4 weeks have passed.

	* Tag bug fix -rc2 4 weeks after -rc1.

	* Tag additional -rc candidates, if needed, to fix critical issues in
	previous -rc releases.

	* Tag final release.

	Release Process
	===============

	.. contents::
	:local:

	Release Administrative Tasks
	----------------------------

	This section describes a few administrative tasks that need to be done for the
	release process to begin. Specifically, it involves:

	* Updating version numbers,

	* Creating the release branch, and

	* Tagging release candidates for the release team to begin testing.

	Create Release Branch
	^^^^^^^^^^^^^^^^^^^^^

	Branch the Git trunk using the following procedure:

	#. Remind developers that the release branching is imminent and to refrain from
	committing patches that might break the build. E.g., new features, large
	patches for works in progress, an overhaul of the type system, an exciting
	new TableGen feature, etc.

	#. Verify that the current git trunk is in decent shape by
	examining nightly tester and buildbot results.

	#. Bump the version in trunk to N.0.0git and tag the commit with llvmorg-N-init.
	If ``X`` is the version to be released, then ``N`` is ``X + 1``.

	::

	$ git tag -a llvmorg-N-init

	#. Clear the release notes in trunk.

	#. Create the release branch from the last known good revision from before the
	version bump. The branch's name is release/X.x where ``X`` is the major version
	number and ``x`` is just the letter ``x``.

	#. All tags and branches need to be created in both the llvm/llvm-project and
	llvm/llvm-test-suite repos.

	Update LLVM Version
	^^^^^^^^^^^^^^^^^^^

	After creating the LLVM release branch, update the release branches'
	``CMakeLists.txt`` versions from '``X.0.0git``' to '``X.0.0``'.

	In addition, the version numbers of all the Bugzilla components must be updated
	for the next release.

	Tagging the LLVM Release Candidates
	^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

	Tag release candidates:

	::

	$ git tag -a llvmorg-X.Y.Z-rcN

	The Release Manager must supply pre-packaged source tarballs for users. This can
	be done with the export.sh script in utils/release.

	Tarballs, release binaries, or any other release artifacts must be uploaded to
	GitHub. This can be done using the github-upload-release.py script in utils/release.

	::

	$ github-upload-release.py upload --token <github-token> --release X.Y.Z-rcN --files <release_files>

	::

	$ ./export.sh -release X.Y.Z -rc $RC

	This will generate source tarballs for each LLVM project being validated, which
	can be uploaded to github for further testing.

	Build The Binary Distribution
	^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

	Creating the binary distribution requires following the instructions
	:doc:`here <ReleaseProcess>`.

	That process will perform both Release+Asserts and Release builds but only
	pack the Release build for upload. You should use the Release+Asserts sysroot,
	normally under ``final/Phase3/Release+Asserts/llvmCore-3.8.1-RCn.install/``,
	for test-suite and run-time benchmarks, to make sure nothing serious has
	passed through the net. For compile-time benchmarks, use the Release version.

	The minimum required version of the tools you'll need are :doc:`here <GettingStarted>`

	Release Qualification Criteria
	------------------------------

	There are no official release qualification criteria. It is up to the
	the release manager to determine when a release is ready. The release manager
	should pay attention to the results of community testing, the number of outstanding
	bugs, and then number of regressions when determining whether or not to make a
	release.

	The community values time based releases, so releases should not be delayed for
	too long unless there are critical issues remaining. In most cases, the only
	kind of bugs that are critical enough to block a release would be a major regression
	from a previous release.

	Official Testing
	----------------

	A few developers in the community have dedicated time to validate the release
	candidates and volunteered to be the official release testers for each
	architecture.

	These will be the ones testing, generating and uploading the official binaries
	to the server, and will be the minimum tests necessary for the release to
	proceed.

	This will obviously not cover all OSs and distributions, so additional community
	validation is important. However, if community input is not reached before the
	release is out, all bugs reported will have to go on the next stable release.

	The official release managers are:

	* Major releases (X.0): Hans Wennborg
	* Stable releases (X.n): Tom Stellard

	The official release testers are volunteered from the community and have
	consistently validated and released binaries for their targets/OSs. To contact
	them, you should email the ``release-testers@lists.llvm.org`` mailing list.

	The official testers list is in the file ``RELEASE_TESTERS.TXT``, in the ``LLVM``
	repository.

	Community Testing
	-----------------

	Once all testing has been completed and appropriate bugs filed, the release
	candidate tarballs are put on the website and the LLVM community is notified.

	We ask that all LLVM developers test the release in any the following ways:

	#. Download ``llvm-X.Y``, ``llvm-test-X.Y``, and the appropriate ``clang``
	binary. Build LLVM. Run ``make check`` and the full LLVM test suite (``make
	TEST=nightly report``).

	#. Download ``llvm-X.Y``, ``llvm-test-X.Y``, and the ``clang`` sources. Compile
	everything. Run ``make check`` and the full LLVM test suite (``make
	TEST=nightly report``).

	#. Download ``llvm-X.Y``, ``llvm-test-X.Y``, and the appropriate ``clang``
	binary. Build whole programs with it (ex. Chromium, Firefox, Apache) for
	your platform.

	#. Download ``llvm-X.Y``, ``llvm-test-X.Y``, and the appropriate ``clang``
	binary. Build your programs with it and check for conformance and
	performance regressions.

	#. Run the :doc:`release process <ReleaseProcess>`, if your platform is
	different than that which is officially supported, and report back errors
	only if they were not reported by the official release tester for that
	architecture.

	We also ask that the OS distribution release managers test their packages with
	the first candidate of every release, and report any new errors in Bugzilla.
	If the bug can be reproduced with an unpatched upstream version of the release
	candidate (as opposed to the distribution's own build), the priority should be
	release blocker.

	During the first round of testing, all regressions must be fixed before the
	second release candidate is tagged.

	In the subsequent stages, the testing is only to ensure that bug
	fixes previously merged in have not created new major problems. *This is not
	the time to solve additional and unrelated bugs!* If no patches are merged in,
	the release is determined to be ready and the release manager may move onto the
	next stage.

	Reporting Regressions
	---------------------

	Every regression that is found during the tests (as per the criteria above),
	should be filled in a bug in Bugzilla with the priority release blocker and
	blocking a specific release.

	To help manage all the bugs reported and which ones are blockers or not, a new
	"[meta]" bug should be created and all regressions blocking that Meta. Once
	all blockers are done, the Meta can be closed.

	If a bug can't be reproduced, or stops being a blocker, it should be removed
	from the Meta and its priority decreased to normal. Debugging can continue,
	but on trunk.

	Merge Requests
	--------------

	You can use any of the following methods to request that a revision from trunk
	be merged into a release branch:

	#. Use the ``utils/release/merge-request.sh`` script which will automatically
	file a bug_ requesting that the patch be merged. e.g. To request revision
	12345 be merged into the branch for the 5.0.1 release:
	``llvm.src/utils/release/merge-request.sh -stable-version 5.0 -r 12345 -user bugzilla@example.com``

	#. Manually file a bug_ with the subject: "Merge r12345 into the X.Y branch",
	enter the commit(s) that you want merged in the "Fixed by Commit(s)" and mark
	it as a blocker of the current release bug. Release bugs are given aliases
	in the form of release-x.y.z, so to mark a bug as a blocker for the 5.0.1
	release, just enter release-5.0.1 in the "Blocks" field.

	#. Reply to the commit email on llvm-commits for the revision to merge and cc
	the release manager.

	.. _bug: https://bugs.llvm.org/

	Release Patch Rules
	-------------------

	Below are the rules regarding patching the release branch:

	#. Patches applied to the release branch may only be applied by the release
	manager, the official release testers or the code owners with approval from
	the release manager.

	#. Release managers are encouraged, but not required, to get approval from code
	owners before approving patches. If there is no code owner or the code owner
	is unreachable then release managers can ask approval from patch reviewers or
	other developers active in that area.

	#. Before RC1 Patches should be limited to bug fixes, important optimization
	improvements, or completion of features that were started before the branch
	was created. As with all phases, release managers and code owners can reject
	patches that are deemed too invasive.

	#. Before RC2 Patches should be limited to bug fixes or backend specific
	improvements that are determined to be very safe.

	#. Before RC3/Final Major Release Patches should be limited to critical
	bugs or regressions.

	#. Bug fix releases Patches should be limited to bug fixes or very safe
	and critical performance improvements. Patches must maintain both API and
	ABI compatibility with the previous major release.


	Merging Patches
	^^^^^^^^^^^^^^^

	Use the ``git cherry-pick -x`` command to merge patches to the release branch:

	#. ``git cherry-pick -x abcdef0``

	#. Run regression tests.

	Release Final Tasks
	-------------------

	The final stages of the release process involves tagging the "final" release
	branch, updating documentation that refers to the release, and updating the
	demo page.

	Update Documentation
	^^^^^^^^^^^^^^^^^^^^

	Review the documentation in the release branch and ensure that it is up
	to date. The "Release Notes" must be updated to reflect new features, bug
	fixes, new known issues, and changes in the list of supported platforms.
	The "Getting Started Guide" should be updated to reflect the new release
	version number tag available from Subversion and changes in basic system
	requirements.

	.. _tag:

	Tag the LLVM Final Release
	^^^^^^^^^^^^^^^^^^^^^^^^^^

	Tag the final release sources:

	::

	$ git tag -a llvmorg-X.Y.Z
	$ git push https://github.com/llvm/llvm-project.git llvmorg-X.Y.Z

	Update the LLVM Website
	^^^^^^^^^^^^^^^^^^^^^^^

	The website must be updated before the release announcement is sent out. Here
	is what to do:

	#. Check out the ``www-releases`` module from GitHub.

	#. Create a new sub-directory ``X.Y.Z`` in the releases directory.

	#. Copy and commit the ``llvm/docs`` and ``LICENSE.txt`` files into this new
	directory.

	#. Update the ``releases/download.html`` file with links to the release
	binaries on GitHub.

	#. Update the ``releases/index.html`` with the new release and link to release
	documentation.

	#. Finally checkout the llvm-www repo and update the main page
	(``index.html`` and sidebar) to point to the new release and release
	announcement.

	Announce the Release
	^^^^^^^^^^^^^^^^^^^^

	Send an email to the list announcing the release, pointing people to all the
	relevant documentation, download pages and bugs fixed.