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:

1. Create the LLVM source distribution.
2. Create the LLVM GCC source distribtuion.
3. 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.

1. Update Documentation
2. Merge Branches
3. Make LibDeps.txt
4. Settle LLVM HEAD
5. Tag LLVM and Create the Release Branch
6. Build LLVM
7. Run 'make check'
8. Run LLVM Test Suite
9. Build the LLVM Source Distributions
10. Build the LLVM GCC Binary Distribution

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.

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.

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.

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.

Tag and branch the CVS HEAD using the following procedure:

1. Request all developers to refrain from committing. Offenders get commit rights taken away (temporarily).
2. 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.
3. 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.
4. Immediately create cvs branches based on the ROOT_RELEASE_XX tag. The tag should be "release_XX" (where XX matches that used for the ROOT_RELEASE_XX tag). This is where the release distribution will be created.
5. Advise developers they can work on CVS HEAD again.
6. The Release Manager and any developers working on the release 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:

   cvs -d <CVS Repository> co -r release_XX llvm
   cvs -d <CVS Repository> co -r release_XX llvm-test
   cvs -d <CVS Repository> co -r release_XX llvm-gcc
   

Build both debug and release (optimized) versions of LLVM on all platforms. Ensure the build is warning and error free on each platform.

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.

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.

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.

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.

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:

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

Creating the LLVM GCC binary distribution requires performing the following steps for each supported platform:

1. 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.
2. Build the libraries in llvm/runtime and install them into the created LLVM GCC installation directory.
3. 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.
4. Add the copyright files and header file fix script.
5. Archive and compress the installation directory. These can be found in previous releases of the LLVM-GCC front-end.

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.