NOTE: THIS DOCUMENT IS A WORK IN PROGRESS!
This document collects information about successfully releasing LLVM to the -public. It is the release manager's guide to ensuring that a high quality build -of LLVM is released. Mostly, its just a bunch of reminders of things to do at -release time so we don't inadvertently ship something that is utility -deficient.
+ +This document contains information about successfully releasing LLVM — + including subprojects: e.g., llvm-gcc and clang — to + the public. It is the Release Manager's responsibility to ensure that a high + quality build of LLVM is released.
+ +LLVM is released on a time based schedule — roughly every 6 months. We + do not normally have dot releases because of the nature of LLVM's incremental + development philosophy. That said, the only thing preventing dot releases for + critical bug fixes from happening is a lack of resources — testers, + machines, time, etc. And, because of the high quality we desire for LLVM + releases, we cannot allow for a truncated form of release qualification.
+ +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 + critial 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!
This section describes a few administrative tasks that need to be done for + the release process to begin. Specifically, it involves:
+ +Branch the Subversion 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 Subversion trunk is in decent shape by + examining nightly tester and buildbot results.
Create the release branch for llvm, llvm-gcc-4.2, + clang, and the test-suite from the last known good + revision. The branch's name is release_XY, where X is + the major and Y the minor release numbers. The branches should be + created using the following commands:
+ ++$ svn copy https://llvm.org/svn/llvm-project/llvm/trunk \ + https://llvm.org/svn/llvm-project/llvm/branches/release_XY + +$ svn copy https://llvm.org/svn/llvm-project/llvm-gcc-4.2/trunk \ + https://llvm.org/svn/llvm-project/llvm-gcc-4.2/branches/release_XY + +$ svn copy https://llvm.org/svn/llvm-project/test-suite/trunk \ + https://llvm.org/svn/llvm-project/test-suite/branches/release_XY + +$ svn copy https://llvm.org/svn/llvm-project/cfe/trunk \ + https://llvm.org/svn/llvm-project/cfe/branches/release_XY ++
Advise developers that they may now check their patches into the + Subversion tree again.
The Release Manager should switch to the release branch, because all + changes to the release will now be done in the branch. The easiest way to + do this is to grab a working copy using the following commands:
+ ++$ svn co https://llvm.org/svn/llvm-project/llvm/branches/release_XY llvm-X.Y + +$ svn co https://llvm.org/svn/llvm-project/llvm-gcc-4.2/branches/release_XY llvm-gcc-4.2-X.Y + +$ svn co https://llvm.org/svn/llvm-project/test-suite/branches/release_XY test-suite-X.Y + +$ svn co https://llvm.org/svn/llvm-project/cfe/branches/release_XY clang-X.Y ++
After creating the LLVM release branch, update the release branches' + autoconf and configure.ac versions from 'X.Ysvn' + to 'X.Y'. Update it on mainline as well to be the next version + ('X.Y+1svn'). Regenerate the configure scripts for both + llvm and the test-suite.
+ +In addition, the version numbers of all the Bugzilla components must be + updated for the next release.
+ +Create release candidates for llvm, llvm-gcc, + clang, and the LLVM test-suite by tagging the branch with + the respective release candidate number. For instance, to create Release + Candidate 1 you would issue the following commands:
+ ++$ svn mkdir https://llvm.org/svn/llvm-project/llvm/tags/RELEASE_XY +$ svn copy https://llvm.org/svn/llvm-project/llvm/branches/release_XY \ + https://llvm.org/svn/llvm-project/llvm/tags/RELEASE_XY/rc1 + +$ svn mkdir https://llvm.org/svn/llvm-project/llvm-gcc-4.2/tags/RELEASE_XY +$ svn copy https://llvm.org/svn/llvm-project/llvm-gcc-4.2/branches/release_XY \ + https://llvm.org/svn/llvm-project/llvm-gcc-4.2/tags/RELEASE_XY/rc1 + +$ svn mkdir https://llvm.org/svn/llvm-project/test-suite/tags/RELEASE_XY +$ svn copy https://llvm.org/svn/llvm-project/test-suite/branches/release_XY \ + https://llvm.org/svn/llvm-project/test-suite/tags/RELEASE_XY/rc1 + +$ svn mkdir https://llvm.org/svn/llvm-project/cfe/tags/RELEASE_XY +$ svn copy https://llvm.org/svn/llvm-project/cfe/branches/release_XY \ + https://llvm.org/svn/llvm-project/cfe/tags/RELEASE_XY/rc1 ++
Similarly, Release Candidate 2 would be named RC2 and so + on. This keeps a permanent copy of the release candidate around for people to + export and build as they wish. The final released sources will be tagged in + the RELEASE_XY directory as Final + (c.f. Tag the LLVM Final Release).
+ +The Release Manager may supply pre-packaged source tarballs for users. This + can be done with the following commands:
+ ++$ svn export https://llvm.org/svn/llvm-project/llvm/tags/RELEASE_XY/rc1 llvm-X.Yrc1 +$ svn export https://llvm.org/svn/llvm-project/llvm-gcc-4.2/tags/RELEASE_XY/rc1 llvm-gcc4.2-X.Yrc1 +$ svn export https://llvm.org/svn/llvm-project/test-suite/tags/RELEASE_XY/rc1 llvm-test-X.Yrc1 +$ svn export https://llvm.org/svn/llvm-project/cfe/tags/RELEASE_XY/rc1 clang-X.Yrc1 + +$ tar -czvf - llvm-X.Yrc1 | gzip > llvm-X.Yrc1.src.tar.gz +$ tar -czvf - llvm-test-X.Yrc1 | gzip > llvm-test-X.Yrc1.src.tar.gz +$ tar -czvf - llvm-gcc4.2-X.Yrc1 | gzip > llvm-gcc-4.2-X.Yrc1.src.tar.gz +$ tar -czvf - clang-X.Yrc1 | gzip > clang-X.Yrc1.src.tar.gz ++
The builds of llvm, llvm-gcc, and clang + must be free of errors and warnings in Debug, Release+Asserts, and + Release builds. If all builds are clean, then the release passes Build + Qualification.
+ +The make options for building the different modes:
+ +| Mode | Options |
|---|---|
| Debug | ENABLE_OPTIMIZED=0 |
| Release+Asserts | ENABLE_OPTIMIZED=1 |
| Release | ENABLE_OPTIMIZED=1 DISABLE_ASSERTIONS=1 |
Build Debug, Release+Asserts, and Release versions + of llvm on all supported platforms. Directions to build + llvm are + here.
+ +Creating the llvm-gcc binary distribution (Release/Optimized) + requires performing the following steps for each supported platform:
+ +Build the llvm-gcc front-end by following the directions in + the README.LLVM file. The front-end must be compiled with C, C++, + Objective-C (Mac only), Objective-C++ (Mac only), and Fortran + support.
Boostrapping must be enabled.
Be sure to build with LLVM_VERSION_INFO=X.Y, where X + is the major and Y is the minor release numbers.
Copy the installation directory to a directory named for the specific + target. For example on Red Hat Enterprise Linux, the directory would be + named llvm-gcc4.2-2.6-x86-linux-RHEL4. Archive and compress the + new directory.
Creating the clang binary distribution + (Debug/Release+Asserts/Release) requires performing the following steps for + each supported platform:
+ +The table below specifies which compilers are used for each Arch/OS + combination when qualifying the build of llvm, llvm-gcc, + and clang.
+ +| Architecture | OS | compiler |
|---|---|---|
| x86-32 | Mac OS 10.5 | gcc 4.0.1 |
| x86-32 | Linux | gcc 4.2.X, gcc 4.3.X |
| x86-32 | FreeBSD | gcc 4.2.X |
| x86-32 | mingw | gcc 3.4.5 |
| x86-64 | Mac OS 10.5 | gcc 4.0.1 |
| x86-64 | Linux | gcc 4.2.X, gcc 4.3.X |
| x86-64 | FreeBSD | gcc 4.2.X |
A release is qualified when it has no regressions from the previous release + (or baseline). Regressions are related to correctness first and performance + second. (We may tolerate some minor performance regressions if they are + deemed necessary for the general quality of the compiler.)
+ +Regressions are new failures in the set of tests that are used to qualify + each product and only include things on the list. Every release will have + some bugs in it. It is the reality of developing a complex piece of + software. We need a very concrete and definitive release criteria that + ensures we have monotonically improving quality on some metric. The metric we + use is described below. This doesn't mean that we don't care about other + criteria, but these are the criteria which we found to be most important and + which must be satisfied before a release can go out
+ +LLVM is qualified when it has a clean test run without a front-end. And it + has no regressions when using either llvm-gcc or clang with + the test-suite from the previous release.
+ +LLVM-GCC is qualified when front-end specific tests in the + llvm regression test suite all pass and there are no regressions in + the test-suite.
+ +We do not use the GCC DejaGNU test suite as release criteria.
+ +Clang is qualified when front-end specific tests in the + llvm dejagnu test suite all pass, clang's own test suite passes + cleanly, and there are no regressions in the test-suite.
+ +| Architecture | OS | llvm-gcc baseline | clang baseline | tests |
|---|---|---|---|---|
| x86-32 | Linux | last release | last release | llvm dejagnu, clang tests, test-suite (including spec) |
| x86-32 | FreeBSD | none | last release | llvm dejagnu, clang tests, test-suite |
| x86-32 | mingw | last release | none | QT |
| x86-64 | Mac OS 10.X | last release | last release | llvm dejagnu, clang tests, test-suite (including spec) |
| x86-64 | Linux | last release | last release | llvm dejagnu, clang tests, test-suite (including spec) |
| x86-64 | FreeBSD | none | last release | llvm dejagnu, clang tests, test-suite |
Merge any work done on branches intended for release into mainline.
+ +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. Ask that all LLVM developers test the release in 2 ways:
+ +Ask LLVM developers to submit the test suite report and make check + results to the list. Verify that there are no regressions from the previous + release. The results are not used to qualify a release, but to spot other + potential problems. For unsupported targets, verify that make check + is at least clean.
+ +During the first round of testing, all regressions must be fixed before the + second release candidate is tagged.
+ +If this is the second round of testing, 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.
+Build LLVM
+ +Below are the rules regarding patching the release branch:
+ +Patches applied to the release branch may only be applied by the + release manager.
During the first round of testing, patches that fix regressions or that + are small and relatively risk free (verified by the appropriate code + owner) are applied to the branch. Code owners are asked to be very + conservative in approving patches for the branch. We reserve the right to + reject any patch that does not fix a regression as previously + defined.
During the remaining rounds of testing, only patches that fix critical + regressions may be applied.
Run "make check" and ensure there are no unexpected failures. If there - are, resolve the failures and go back to step 2.
+ +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.
+Run the llvm-test suite and ensure there are no unacceptable failures. - If there are, resolve the failures and go back to step 2.
+ +Review the documentation 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 avaiable from + Subversion and changes in basic system requirements. Merge both changes from + mainline into the release branch.
+Rebuild the LibDeps.txt target in utils/llvm-config. This makes sure that - the llvm-config utility remains relevant for the release, reflecting any - changes in the library dependencies.
+ +Tag the final release sources using the following procedure:
+ ++$ svn copy https://llvm.org/svn/llvm-project/llvm/branches/release_XY \ + https://llvm.org/svn/llvm-project/llvm/tags/RELEASE_XY/Final + +$ svn copy https://llvm.org/svn/llvm-project/llvm-gcc-4.2/branches/release_XY \ + https://llvm.org/svn/llvm-project/llvm-gcc-4.2/tags/RELEASE_XY/Final + +$ svn copy https://llvm.org/svn/llvm-project/test-suite/branches/release_XY \ + https://llvm.org/svn/llvm-project/test-suite/tags/RELEASE_XY/Final + +$ svn copy https://llvm.org/svn/llvm-project/cfe/branches/release_XY \ + https://llvm.org/svn/llvm-project/cfe/tags/RELEASE_XY/Final ++
Tag the release.
+ +The LLVM demo page must be updated to use the new release. This consists of + using the new llvm-gcc binary and building LLVM.
+Build the distribution, ensuring it is installable and working
+ +The website must be updated before the release announcement is sent out. Here + is what to do:
+ +Release the distribution tarball to the public.
+ +Have Chris send out the release announcement when everything is finished.
+
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