1================================= 2How To Release LLVM To The Public 3================================= 4 5Introduction 6============ 7 8This document contains information about successfully releasing LLVM --- 9including sub-projects: e.g., ``clang`` and ``compiler-rt`` --- to the public. 10It is the Release Manager's responsibility to ensure that a high quality build 11of LLVM is released. 12 13If you're looking for the document on how to test the release candidates and 14create the binary packages, please refer to the :doc:`ReleaseProcess` instead. 15 16.. _timeline: 17 18Release Timeline 19================ 20 21LLVM is released on a time based schedule --- with major releases roughly 22every 6 months. In between major releases there may be dot releases. 23The release manager will determine if and when to make a dot release based 24on feedback from the community. Typically, dot releases should be made if 25there are large number of bug-fixes in the stable branch or a critical bug 26has been discovered that affects a large number of users. 27 28Unless otherwise stated, dot releases will follow the same procedure as 29major releases. 30 31The release process is roughly as follows: 32 33* Set code freeze and branch creation date for 6 months after last code freeze 34 date. Announce release schedule to the LLVM community and update the website. 35 36* Create release branch and begin release process. 37 38* Send out release candidate sources for first round of testing. Testing lasts 39 7-10 days. During the first round of testing, any regressions found should be 40 fixed. Patches are merged from mainline into the release branch. Also, all 41 features need to be completed during this time. Any features not completed at 42 the end of the first round of testing will be removed or disabled for the 43 release. 44 45* Generate and send out the second release candidate sources. Only *critical* 46 bugs found during this testing phase will be fixed. Any bugs introduced by 47 merged patches will be fixed. If so a third round of testing is needed. 48 49* The release notes are updated. 50 51* Finally, release! 52 53* Announce bug fix release schedule to the LLVM community and update the website. 54 55* Tag bug fix -rc1 after 4 weeks have passed. 56 57* Tag bug fix -rc2 4 weeks after -rc1. 58 59* Tag additional -rc candidates, if needed, to fix critical issues in 60 previous -rc releases. 61 62* Tag final release. 63 64Release Process 65=============== 66 67.. contents:: 68 :local: 69 70Release Administrative Tasks 71---------------------------- 72 73This section describes a few administrative tasks that need to be done for the 74release process to begin. Specifically, it involves: 75 76* Updating version numbers, 77 78* Creating the release branch, and 79 80* Tagging release candidates for the release team to begin testing. 81 82Create Release Branch 83^^^^^^^^^^^^^^^^^^^^^ 84 85Branch the Git trunk using the following procedure: 86 87#. Remind developers that the release branching is imminent and to refrain from 88 committing patches that might break the build. E.g., new features, large 89 patches for works in progress, an overhaul of the type system, an exciting 90 new TableGen feature, etc. 91 92#. Verify that the current git trunk is in decent shape by 93 examining nightly tester and buildbot results. 94 95#. Bump the version in trunk to N.0.0git and tag the commit with llvmorg-N-init. 96 If ``X`` is the version to be released, then ``N`` is ``X + 1``. 97 98:: 99 100 $ git tag -a llvmorg-N-init 101 102#. Clear the release notes in trunk. 103 104#. Create the release branch from the last known good revision from before the 105 version bump. The branch's name is release/X.x where ``X`` is the major version 106 number and ``x`` is just the letter ``x``. 107 108#. All tags and branches need to be created in both the llvm/llvm-project and 109 llvm/llvm-test-suite repos. 110 111Update LLVM Version 112^^^^^^^^^^^^^^^^^^^ 113 114After creating the LLVM release branch, update the release branches' 115``CMakeLists.txt`` versions from '``X.0.0git``' to '``X.0.0``'. 116 117In addition, the version numbers of all the Bugzilla components must be updated 118for the next release. 119 120Tagging the LLVM Release Candidates 121^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 122 123Tag release candidates: 124 125:: 126 127 $ git tag -a llvmorg-X.Y.Z-rcN 128 129The Release Manager must supply pre-packaged source tarballs for users. This can 130be done with the export.sh script in utils/release. 131 132Tarballs, release binaries, or any other release artifacts must be uploaded to 133GitHub. This can be done using the github-upload-release.py script in utils/release. 134 135:: 136 137 $ github-upload-release.py upload --token <github-token> --release X.Y.Z-rcN --files <release_files> 138 139:: 140 141 $ ./export.sh -release X.Y.Z -rc $RC 142 143This will generate source tarballs for each LLVM project being validated, which 144can be uploaded to github for further testing. 145 146Build The Binary Distribution 147^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 148 149Creating the binary distribution requires following the instructions 150:doc:`here <ReleaseProcess>`. 151 152That process will perform both Release+Asserts and Release builds but only 153pack the Release build for upload. You should use the Release+Asserts sysroot, 154normally under ``final/Phase3/Release+Asserts/llvmCore-3.8.1-RCn.install/``, 155for test-suite and run-time benchmarks, to make sure nothing serious has 156passed through the net. For compile-time benchmarks, use the Release version. 157 158The minimum required version of the tools you'll need are :doc:`here <GettingStarted>` 159 160Release Qualification Criteria 161------------------------------ 162 163There are no official release qualification criteria. It is up to the 164the release manager to determine when a release is ready. The release manager 165should pay attention to the results of community testing, the number of outstanding 166bugs, and then number of regressions when determining whether or not to make a 167release. 168 169The community values time based releases, so releases should not be delayed for 170too long unless there are critical issues remaining. In most cases, the only 171kind of bugs that are critical enough to block a release would be a major regression 172from a previous release. 173 174Official Testing 175---------------- 176 177A few developers in the community have dedicated time to validate the release 178candidates and volunteered to be the official release testers for each 179architecture. 180 181These will be the ones testing, generating and uploading the official binaries 182to the server, and will be the minimum tests *necessary* for the release to 183proceed. 184 185This will obviously not cover all OSs and distributions, so additional community 186validation is important. However, if community input is not reached before the 187release is out, all bugs reported will have to go on the next stable release. 188 189The official release managers are: 190 191* Major releases (X.0): Hans Wennborg 192* Stable releases (X.n): Tom Stellard 193 194The official release testers are volunteered from the community and have 195consistently validated and released binaries for their targets/OSs. To contact 196them, you should email the ``[email protected]`` mailing list. 197 198The official testers list is in the file ``RELEASE_TESTERS.TXT``, in the ``LLVM`` 199repository. 200 201Community Testing 202----------------- 203 204Once all testing has been completed and appropriate bugs filed, the release 205candidate tarballs are put on the website and the LLVM community is notified. 206 207We ask that all LLVM developers test the release in any the following ways: 208 209#. Download ``llvm-X.Y``, ``llvm-test-X.Y``, and the appropriate ``clang`` 210 binary. Build LLVM. Run ``make check`` and the full LLVM test suite (``make 211 TEST=nightly report``). 212 213#. Download ``llvm-X.Y``, ``llvm-test-X.Y``, and the ``clang`` sources. Compile 214 everything. Run ``make check`` and the full LLVM test suite (``make 215 TEST=nightly report``). 216 217#. Download ``llvm-X.Y``, ``llvm-test-X.Y``, and the appropriate ``clang`` 218 binary. Build whole programs with it (ex. Chromium, Firefox, Apache) for 219 your platform. 220 221#. Download ``llvm-X.Y``, ``llvm-test-X.Y``, and the appropriate ``clang`` 222 binary. Build *your* programs with it and check for conformance and 223 performance regressions. 224 225#. Run the :doc:`release process <ReleaseProcess>`, if your platform is 226 *different* than that which is officially supported, and report back errors 227 only if they were not reported by the official release tester for that 228 architecture. 229 230We also ask that the OS distribution release managers test their packages with 231the first candidate of every release, and report any *new* errors in Bugzilla. 232If the bug can be reproduced with an unpatched upstream version of the release 233candidate (as opposed to the distribution's own build), the priority should be 234release blocker. 235 236During the first round of testing, all regressions must be fixed before the 237second release candidate is tagged. 238 239In the subsequent stages, the testing is only to ensure that bug 240fixes previously merged in have not created new major problems. *This is not 241the time to solve additional and unrelated bugs!* If no patches are merged in, 242the release is determined to be ready and the release manager may move onto the 243next stage. 244 245Reporting Regressions 246--------------------- 247 248Every regression that is found during the tests (as per the criteria above), 249should be filled in a bug in Bugzilla with the priority *release blocker* and 250blocking a specific release. 251 252To help manage all the bugs reported and which ones are blockers or not, a new 253"[meta]" bug should be created and all regressions *blocking* that Meta. Once 254all blockers are done, the Meta can be closed. 255 256If a bug can't be reproduced, or stops being a blocker, it should be removed 257from the Meta and its priority decreased to *normal*. Debugging can continue, 258but on trunk. 259 260Backport Requests 261----------------- 262 263Instructions for requesting a backport to a stable branch can be found :doc:`here <GitHub>`. 264 265Release Patch Rules 266------------------- 267 268Below are the rules regarding patching the release branch: 269 270#. Patches applied to the release branch may only be applied by the release 271 manager, the official release testers or the code owners with approval from 272 the release manager. 273 274#. Release managers are encouraged, but not required, to get approval from code 275 owners before approving patches. If there is no code owner or the code owner 276 is unreachable then release managers can ask approval from patch reviewers or 277 other developers active in that area. 278 279#. *Before RC1* Patches should be limited to bug fixes, important optimization 280 improvements, or completion of features that were started before the branch 281 was created. As with all phases, release managers and code owners can reject 282 patches that are deemed too invasive. 283 284#. *Before RC2* Patches should be limited to bug fixes or backend specific 285 improvements that are determined to be very safe. 286 287#. *Before RC3/Final Major Release* Patches should be limited to critical 288 bugs or regressions. 289 290#. *Bug fix releases* Patches should be limited to bug fixes or very safe 291 and critical performance improvements. Patches must maintain both API and 292 ABI compatibility with the previous major release. 293 294 295Merging Patches 296^^^^^^^^^^^^^^^ 297 298Use the ``git cherry-pick -x`` command to merge patches to the release branch: 299 300#. ``git cherry-pick -x abcdef0`` 301 302#. Run regression tests. 303 304Release Final Tasks 305------------------- 306 307The final stages of the release process involves tagging the "final" release 308branch, updating documentation that refers to the release, and updating the 309demo page. 310 311Update Documentation 312^^^^^^^^^^^^^^^^^^^^ 313 314Review the documentation in the release branch and ensure that it is up 315to date. The "Release Notes" must be updated to reflect new features, bug 316fixes, new known issues, and changes in the list of supported platforms. 317The "Getting Started Guide" should be updated to reflect the new release 318version number tag available from Subversion and changes in basic system 319requirements. 320 321.. _tag: 322 323Tag the LLVM Final Release 324^^^^^^^^^^^^^^^^^^^^^^^^^^ 325 326Tag the final release sources: 327 328:: 329 330 $ git tag -a llvmorg-X.Y.Z 331 $ git push https://github.com/llvm/llvm-project.git llvmorg-X.Y.Z 332 333Update the LLVM Website 334^^^^^^^^^^^^^^^^^^^^^^^ 335 336The website must be updated before the release announcement is sent out. Here 337is what to do: 338 339#. Check out the ``www-releases`` module from GitHub. 340 341#. Create a new sub-directory ``X.Y.Z`` in the releases directory. 342 343#. Copy and commit the ``llvm/docs`` and ``LICENSE.txt`` files into this new 344 directory. 345 346#. Update the ``releases/download.html`` file with links to the release 347 binaries on GitHub. 348 349#. Update the ``releases/index.html`` with the new release and link to release 350 documentation. 351 352#. Finally checkout the llvm-www repo and update the main page 353 (``index.html`` and sidebar) to point to the new release and release 354 announcement. 355 356Announce the Release 357^^^^^^^^^^^^^^^^^^^^ 358 359Send an email to the list announcing the release, pointing people to all the 360relevant documentation, download pages and bugs fixed. 361