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, it's just a bunch of reminders of things to do at -release time so we don't inadvertently ship something that is utility -deficient.

- -

-There are three main tasks for building a release of LLVM: +

+ 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. +

+ +

+ The following is the basic criteria for releasing LLVM: +

+ +

Successful configure and build.
Clean 'make check'.
No regressions in the testsuite from the previous release. This may + include performance regressions for major benchmarks.

+The release manager should attempt to have a release every 3-4 months because LLVM +does time based releases (instead of feature based). The release schedule should +be roughly as follows:

Create the LLVM source distribution.
Create the LLVM GCC source distribtuion.
Create a set of LLVM GCC binary distribtuions for each supported - platform. These binary distributions must include compiled versions - of the libraries found in llvm/runtime from the LLVM - source distribution created in Step 1.
Set code freeze and branch creation date for 3 months after last release +date. Announce release schedule to the LLVM community and update the website.
Create release branch and begin release process.
Send out pre-release for first round of testing. Testing will last 7-10 days. +During the first round of testing, regressions should be found and fixed. Patches +are merged from mainline to the release branch.
Generate and send out second pre-release. Bugs found during this time will +not be fixed unless absolutely critical. Bugs introduce by patches merged in +will be fixed and if so, a 3rd round of testing is needed.
The release notes should be updated during the first and second round of +pre-release testing.
Finally, release!

Update Documentation
Merge Branches
Make LibDeps.txt
Settle LLVM HEAD
Tag LLVM and Create the Release Branch
Create Release Branch
Update LLVM Version
Build the LLVM Source Distributions
Build LLVM
Build the LLVM GCC Binary Distribution
Build RPM Packages (optional)
Run 'make check'
Run LLVM Test Suite
Build the LLVM Source Distributions
Build the LLVM GCC Binary Distribution
Pre-Release Testing
Tag the LLVM Release Branch
Update Documentation
Update the LLVM Demo Page
Update the LLVM Website
Announce the Release

- Review the documentation and ensure that it is up to date. The Release Notes - must be updated to reflect 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 CVS and changes in - basic system requirements. +

Branch the Subversion HEAD using the following procedure:

+
Verify that the current Subversion HEAD is in decent shape by examining nightly + tester results.
+
Request all developers to refrain from committing. Offenders get commit + rights taken away (temporarily).

Create the release branch for llvm, llvm-gcc4.0, + llvm-gcc4.2, and the test-suite. The + branch name will be release_XX, where XX is the major and + minor release numbers. These branches can be created without checking out + anything from subversion.

+ +

+svn copy https://llvm.org/svn/llvm-project/llvm/trunk \
+         https://llvm.org/svn/llvm-project/llvm/branches/release_XX
+svn copy https://llvm.org/svn/llvm-project/llvm-gcc-4.0/trunk \
+         https://llvm.org/svn/llvm-project/llvm-gcc-4.0/branches/release_XX
+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_XX
+svn copy https://llvm.org/svn/llvm-project/test-suite/trunk \
+         https://llvm.org/svn/llvm-project/test-suite/branches/release_XX
+

+ +

+
Advise developers they can work on Subversion HEAD again.

The Release Manager should switch to the release branch (as all changes + to the release will now be done in the branch). The easiest way to do this + is to grab another working copy using the following commands:

+ +

+svn co https://llvm.org/svn/llvm-project/llvm/branches/release_XX
+svn co https://llvm.org/svn/llvm-project/llvm-gcc-4.0/branches/release_XX
+svn co https://llvm.org/svn/llvm-project/llvm-gcc-4.2/branches/release_XX
+svn co https://llvm.org/svn/llvm-project/test-suite/branches/release_XX
+

-Merge any work done on branches intended for release into mainline. Finish and -commit all new features or bug fixes that are scheduled to go into the release. -Work that is not to be incorporated into the release should not be merged from -branchs or commited from developer's working directories. -

- -

-From this point until the release branch is created, developers should -not -commit changes to the llvm and llvm-gcc CVS repositories unless it is a bug -fix for the release. -

+ After creating the LLVM release branch, update the release branches' + autoconf/configure.ac version from X.Xsvn to just X.X. Update it on mainline + as well to be the next version (X.X+1svn). Regenerated the configure script + for both. This must be done for both llvm and the test-suite. +

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

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.

+ Create source distributions for LLVM, LLVM GCC, and the LLVM Test Suite by + exporting the source from Subversion and archiving it. This can be done with + the following commands: +

- Use the nightly test reports and 'make check' (deja-gnu based tests) to - ensure that recent changes and merged branches have not destabilized LLVM. - Platforms which are used less often should be given special attention as they - are the most likely to break from commits from the previous step. + Build both debug and release (optimized) versions of LLVM on all + platforms. Ensure the build is warning and error free on each platform. + Note that when building the LLVM GCC Binary, use a release build of LLVM.

Tag and branch the CVS HEAD using the following procedure:

- Request all developers to refrain from committing. Offenders get commit - rights taken away (temporarily). -

+ Creating the LLVM GCC binary distribution (release/optimized) requires + performing the following steps for each supported platform: +

- The Release Manager updates his/her llvm, llvm-test, and llvm-gcc source - trees with the - latest sources from mainline CVS. The Release Manage may want to consider - using a new working directory for this to keep current uncommitted work - separate from release work. + Build the LLVM GCC front-end by following the directions in the README.LLVM + file. Be sure to build with LLVM_VERSION_INFO=X.X, where X is the major and + minor release numbers.
- The Release Manager tags his/her llvm, llvm-test, and llvm-gcc working - directories with - "ROOT_RELEASE_XX" where XX is the major and minor - release numbers (you can't have . in a cvs tag name). So, for Release 1.2, - XX=12 and for Release 1.10, XX=110. + 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-gcc4.0-2.1-x86-linux-RHEL4. Archive and compress the new directory.

+ Using the newly built llvm-gcc and llvm, reconfigure llvm to locate llvm-gcc. + Run make check and ensure there are no unexpected failures. If there + are, resolve the failures or file a bug. If there is a fix commited to mainline, + merge back into the release branch, and restart testing by + re-building LLVM and llvm-gcc. If no + fix will be made, XFAIL the test and commit back to the release branch. +

- Advise developers they can work on CVS HEAD again. -

+ Ensure that 'make check' passes on all platforms for all targets. The + test suite must complete with "0 unexpected failures" before sending out the + pre-releases for testing. +

+ Run the llvm-test suite and ensure there are no unacceptable + failures. Unacceptable failures are regression from the previous release + and (optionally) major performance regressions from the previous release. + If a regression is found a bug is filled, but the pre-releases may still go + out.

- Build both debug and release (optimized) versions of LLVM on all - platforms. Ensure the build is warning and error free on each platform. + You can, optionally, create source and binary RPM packages for LLVM. These may + make it easier to get LLVM into a distribution. This can be done with the + following commands:

+make dist        # Build the distribution source tarball
+make dist-check  # Check that the source tarball can build itself.
+cp llvm-M.m.tar.gz /usr/src/redhat/SOURCES  # Required by rpmbuild
+make srpm # for source rpm
+make rpm  # for binary rpm
+

- Build a new version of the LLVM GCC front-end after building the LLVM tools. - Once that is complete, go back to the LLVM source tree and build and install - the llvm/runtime libraries. + First, use make dist to simply build the distribution. Any failures + need to be corrected (on the branch). Once make dist can be + successful, do make dist-check. This target will do the same thing as + the 'dist' target but also test that distribution to make sure it can build + itself and runs make check as well. This ensures that needed files + are not missing and that the src tarball can be successfully unpacked, built, + installed, and cleaned. Once you have a reliable tarball, you need to copy it + to the /usr/src/redhat/SOURCES directory which is a requirement of + the rpmbuild tool. The last two make invocations just run rpmbuild to + build either a source (srpm) or binary (rpm) RPM package.

Run make check and ensure there are no unexpected failures. If - there are, resolve the failures, commit them back into the release branch, - and restart testing by re-building LLVM. -

+ Once all testing has been completed and appropriate bugs filed, the pre-release + tar balls may be put on the website and the LLVM community is notified. Ask that + all LLVM developers test the release in 2 ways:

Download llvm-X.X, llvm-test-X.X, and the appropriate llvm-gcc4 binary. + Run "make check" and the full llvm-test suite (make TEST=nightly report).
+
Download llvm-X.X, llvm-test-X.X, and the llvm-gcc4 source. Compile + everything. Run "make check" and the full llvm-test suite (make TEST=nightly + report).

Ask LLVM developers to submit the report and make check results to the list. + Verify that there are no regressions from the previous release. For + unsupported targets, verify that make check at least is clean.

+ +

The first round of pre-release testing will be the longest. During this time, + all regressions must be fixed before the second pre-release is created (repeat + steps 4-8).

+ +

If this is the second round of testing, this is only to ensure the 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 step.

Tag the release branch using the following procedure:

+svn copy https://llvm.org/svn/llvm-project/llvm/branches/release_XX \
+         https://llvm.org/svn/llvm-project/llvm/tags/RELEASE_XX
+svn copy https://llvm.org/svn/llvm-project/llvm-gcc-4.0/branches/release_XX \
+         https://llvm.org/svn/llvm-project/llvm-gcc-4.0/tags/RELEASE_XX
+svn copy https://llvm.org/svn/llvm-project/llvm-gcc-4.2/branches/release_XX \
+         https://llvm.org/svn/llvm-project/llvm-gcc-4.2/tags/RELEASE_XX
+svn copy https://llvm.org/svn/llvm-project/test-suite/branches/release_XX \
+         https://llvm.org/svn/llvm-project/test-suite/tags/RELEASE_XX
+

- Ensure that 'make check' passes on all platforms for all targets. If certain - failures cannot be resolved before release time, determine if marking them - XFAIL is appropriate. If not, fix the bug and go back. The test suite must - complete with "0 unexpected failures" for release. + Review the documentation and ensure that it is up to date. The Release Notes + must be updated to reflect 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.

Run the llvm-test suite and ensure there are no unacceptable failures. - If there are, resolve the failures and go back to - re-building LLVM. The test suite - should be run in Nightly Test mode. All tests must pass. +

+ The LLVM demo page must be updated to use the new release. This consists of + using the llvm-gcc binary and building LLVM. Update the website demo page + configuration to use the new release.

- Create source distributions for LLVM, LLVM GCC, and the LLVM Test Suite by - exporting the source - from CVS and archiving it. This can be done with the following commands: -

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

Check out the website module from CVS.
Create a new subdirectory X.X in the releases directory.
Commit the llvm, test-suite, llvm-gcc source, + and llvm-gcc binaries in this new directory.
Copy and commit the llvm/docs and LICENSE.txt + files into this new directory. The docs should be built with BUILD_FOR_WEBSITE=1.
Commit the index.html to the release/X.X directory to redirect (use from previous + release.
Update the releases/download.html file with the new release.
Update the releases/index.html with the new release and link to + release documentation.
Finally, update the main page (index.html and sidebar) to + point to the new release and release announcement. Make sure this all gets + commited back into Subversion.

Have Chris send out the release announcement when everything is finished.

- cvs -d <CVS Repository> export -r release_XX llvm
- cvs -d <CVS Repository> export -r release_XX llvm-test
- cvs -d <CVS Repository> export -r release_XX llvm-gcc
- mkdir cfrontend; mv llvm-gcc cfrontend/src
- tar -cvf - llvm | gzip > llvm-X.X.tar.gz
- tar -cvf - llvm-test | gzip > llvm-test-X.X.tar.gz
- tar -cvf - cfrontend/src | gzip > cfrontend-X.X.source.tar.gz
+ The first thing you need to understand is that there are multiple make targets + to support this feature. Here's an overview, we'll delve into the details + later.

- +

distdir - builds the distribution directory from which the + distribution will be packaged
dist - builds each of the distribution tarballs (tar.gz, + tar.bzip2, .zip). These can be built individually as well, with separate + targets.
dist-check - this is identical to dist but includes a + check on the distribution that ensures the tarball can: unpack + successfully, compile correctly, pass 'make check', and pass + 'make clean'.
dist-clean- this just does a normal clean but also cleans up the + stuff generated by the other three dist targets (above).

+ +

+ Okay, that's the basic functionality. When making a release, we want to ensure + that the tree you build the distribution from passes + dist-check. Beyond fixing the usual bugs, there is generally one + impediment to making the release in this fashion: missing files. The + dist-check process guards against that possibility. It will either + fail and that failure will indicate what's missing, or it will succeed meaning + that it has proved that the tarballs can actually succeed in building LLVM + correctly and that it passes make check. +

- Creating the LLVM GCC binary distribution requires performing the following - steps for each supported platform: + This target builds the distribution directory which is the directory from + which the tarballs are generated. The distribution directory has the same + name as the release, e.g. LLVM-1.7). This target goes through the following + process:

- Build the LLVM GCC front-end. The LLVM GCC front-end must be installed in - a directory named cfrontend/<platform>/llvm-gcc. For - example, the Sparc/Solaris directory is named - cfrontend/sparc/llvm-gcc. -
First, if there was an old distribution directory (for the current + release), it is removed in its entirety and you see Removing old + LLVM-1.7
Second, it issues a make all ENABLE_OPTIMIZED=3D1 to ensure + that the everything in your tree can be built in release mode. Often + times there are discrepancies in building between debug and release + modes so it enforces release mode first. If that fails, the + distdir target fails too. This is preceded by the message + Making 'all' to verify build.
Next, it traverses your source tree and copies it to a new directory + that has the name of the release (LLVM-M.m in our current + case). This is the directory that will get tar'd. It contains all the + software that needs to be in the distribution. During the copying + process, it omits generated files, SVN directories, and any other + "cruft" that's in your build tree. This is done to eliminate the + possibility of huge distribution tarballs that include useless or + irrelevant stuff in them. This is the trickiest part of making the + distribution. Done manually you will either include stuff that + shouldn't be in the distribution or exclude stuff that should. This + step is preceded by the message Building Distribution Directory + LLVM-1.7
The distribution directory is then traversed and all CVS or + .svn directories are removed. You see: Eliminating CVS/.svn + directories from distribution
The recursive dist-hook target is executed. This gives each + directory a chance to modify the distribution in some way (more on this + below).
The distribution directory is traversed and the correct file + permissions and modes are set based on the type of file.

- Build the libraries in llvm/runtime and install them into the - created LLVM GCC installation directory. -

+ To control the process of making the distribution directory correctly, each + Makefile can utilize two features: +

- For systems with non-distributable header files (e.g. Solaris), manually - remove header files that the GCC build process has "fixed." This process - is admittedly painful, but not as bad as it looks; these header files are - almost always easily identifiable with simple grep expressions and are - installed in only a few directories in the GCC installation directory. -

EXTRA_DIST - this make variable specifies which files + it should distribute. By default, all source files are automatically + included for distribution as well as certain well known files + (see DistAlways variable in Makefile.rules for details). Each Makefile + specifies, via the EXTRA_DIST variable, which additional files + need to be distributed. Only those files that are needed to build LLVM + should be added to EXTRA_DIST. EXTRA_DIST contains a + list of file or directory names that should be distributed. For example, + the top level Makefile contains EXTRA_DIST := test llvm.spec + include. This means that in addition to regular things that are + distributed at the top level (CREDITS.txt, LICENSE.txt, etc.) + the distribution should contain the entire test and + include directories as well as the llvm.spec file.
dist-hook - this make target can be used to alter the + content of the distribution directory. For example, in the top level + Makefile there is some logic to eliminate files in the include + subtree that are generated by the configure script. These should not be + distributed. Similarly, any dist-hook target found in any + directory can add or remove or modify things just before it gets + packaged. Any transformation is permitted. Generally, not much is + needed.

- Add the copyright files and header file fix script. -

+ You will see various messages if things go wrong: +

- Archive and compress the installation directory. These can be found in - previous releases of the LLVM-GCC front-end. -

During the copying process, any files that are missing will be flagged + with: ===== WARNING: Distribution Source 'dir/file' Not Found! + These must be corrected by either adding the file or removing it from + EXTRA_DIST.
If you build the distribution with VERBOSE=1, then you might + also see: Skipping non-existent 'dir/file' in certain cases + where it's okay to skip the file.
The target can fail if any of the things it does fail. Error messages + should indicate what went wrong.

+ This target does exactly what distdir target does, but also includes + assembling the tarballs. There are actually four related targets here: +

+ +

dist-gzip: package the gzipped distribution tar + file. The distribution directory is packaged into a single file ending + in .tar.gz which is gzip compressed.
dist-bzip2: package the bzip2 distribution tar file. + The distribution directory is packaged into a single file ending in + .tar.bzip2 which is bzip2 compressed.
dist-zip: package the zip distribution file. The + distribution directory is packaged into a single file ending in + .zip which is zip compressed.
dist: does all three, dist-gzip, dist-bzip2, + dist-zip

+ This target checks the distribution. The basic idea is that it unpacks the + distribution tarball and ensures that it can build. It takes the following + actions: +

+ +

It depends on the dist-gzip target which, if it hasn't already + been built, builds the gzip tar bundle (see dist and distdir + above).
removes any pre-existing _distcheckdir at the top level.
creates a new _distcheckdir directory at the top level.
creates a build subdirectory and an install + subdirectory under _distcheckdir.
unzips and untars the release tarball into _distcheckdir, + creating LLVM-1.7 directory (from the tarball).
in the build subdirectory, it configures with appropriate options to + build from the unpacked source tarball into the build directory + with installation in the install directory.
runs make all
runs make check
runs make install
runs make uninstall
runs make dist
runs make clean
runs make dist-clean

+ +

+ If it can pass all that, the distribution will be deemed distribution worth y + and you will see: +

+ +

===== LLVM-1.7.tar.gz Ready For Distribution =====

+ +

+ This means the tarball should then be tested on other platforms and have the + nightly test run against it. If those all pass, THEN it is ready for + distribution. +

+ +

+ A note about disk space: using dist-check will easily triple the + amount of disk space your build tree is using. You might want to check + available space before you begin. +

Release the distribution tarball to the public. This consists of generating - several tarballs. The first set, the source distributions, are automatically - generated by the "make dist" and "make dist-check". There are gzip, bzip2, and - zip versions of these bundles.

The second set of tarballs is the binary release. When "make dist-check" - succeeds, it will have created an _install directory into which it installed - the binary release. You need to rename that directory as "llvm" and then - create tarballs from the contents of that "llvm" directory.

Finally, use rpm to make an rpm package based on the llvm.spec file. Don't - forget to update the version number, documentation, etc. in the llvm.spec - file.

+ In addition to doing a normal clean, this target will clean up the + files and directories created by the distribution targets. In particular the + distribution directory (LLVM-X.X), check directory + (_distcheckdir), and the various tarballs will be removed. You do + this after the release has shipped and you no longer need this stuff in your + build tree. +