docs/HowToReleaseLLVM.html

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  10 <div class="doc_title">How To Release LLVM To The Public</div>
  11 <ol>
  12   <li><a href="#introduction">Introduction</a></li>
  13   <li><a href="#criteria">Qualification Criteria</a></li>
  14   <li><a href="#introduction">Release Timeline</a></li>
  15   <li><a href="#process">Release Process</a></li>
  16 </ol>
  17 <div class="doc_author">
  18   <p>Written by <a href="mailto:tonic@nondot.org">Tanya Lattner</a>,
  19   <a href="mailto:rspencer@x10sys.com">Reid Spencer</a>,
  20   <a href="mailto:criswell@cs.uiuc.edu">John Criswell</a>
  21   </p>
  22 </div>
  23
  24 <!-- *********************************************************************** -->
  25 <div class="doc_section"><a name="introduction">Introduction</a></div>
  26 <!-- *********************************************************************** -->
  27
  28 <div class="doc_text">
  29   <p>
  30   This document collects information about successfully releasing LLVM
  31   (including subprojects llvm-gcc and Clang) to the public.
  32   It is the release manager's responsibility to ensure that a high quality
  33   build of LLVM is released.
  34   </p>
  35 </div>
  36
  37 <!-- *********************************************************************** -->
  38 <div class="doc_section"><a name="process">Release Timeline</a></div>
  39 <!-- *********************************************************************** -->
  40 <div class="doc_text">
  41   <p>LLVM is released on a time based schedule (currently every 6 months). We
  42   do not have dot releases because of the nature of LLVM incremental
  43   developement philosophy. The release schedule is roughly as follows:
  44   </p>
  45 <ol>
  46 <li>Set code freeze and branch creation date for 6 months after last code freeze
  47 date. Announce release schedule to the LLVM community and update the website.</li>
  48 <li>Create release branch and begin release process. </li>
  49 <li>Send out pre-release for first round of testing. Testing will last 7-10 days.
  50 During the first round of testing, regressions should be found and fixed. Patches
  51 are merged from mainline to the release branch.</li>
  52 <li>Generate and send out second pre-release. Bugs found during this time will
  53 not be fixed unless absolutely critical. Bugs introduce by patches merged in
  54 will be fixed and if so, a 3rd round of testing is needed.</li>
  55 <li>The release notes should be updated during the first and second round of
  56 pre-release testing.</li>
  57 <li>Finally, release!</li>
  58 </ol>
  59 </div>
  60
  61
  62 <!-- *********************************************************************** -->
  63 <div class="doc_section"><a name="process">Release Process</a></div>
  64 <!-- *********************************************************************** -->
  65
  66 <div class="doc_text">
  67   <ol>
  68     <li><a href="#release-admin">Release Administrative Tasks</a></li>
  69     <ol>
  70     <li><a href="#branch">Create Release Branch</a></li>
  71     <li><a href="#verchanges">Update Version Numbers</a></li>
  72     </ol>
  73     <li><a href="#release-build">Building the Release</a></li>
  74     <ol>
  75     <li><a href="#dist">Build the LLVM Source Distributions</a></li>
  76     <li><a href="#build">Build LLVM</a></li>
  77     <li><a href="#llvmgccbin">Build the LLVM-GCC Binary Distribution</a></li>
  78     <li><a href="#clangbin">Build the Clang Binary Distribution</a></li>
  79     <li><a href="#target-build">Target Specific Build Details</a></li>
  80     </ol>
  81
  82     <li><a href="#release-qualify">Release Qualification Criteria</a></li>
  83     <ol>
  84     <li><a href="#llvm-qualify">Qualify LLVM</a></li>
  85     <li><a href="#llvmgcc-qualify">Qualify LLVM-GCC</a></li>
  86     <li><a href="#clang-qualify">Qualify Clang</a></li>
  87     <li><a href="#targets">Specific Target Qualification Details</a></li>
  88     </ol>
  89
  90     <li><a href="#commTest">Community Testing</a></li>
  91     <li><a href="#release-patch">Release Patch Rules</a></li>
  92
  93
  94     <li><a href="#release-final">Release final tasks</a></li>
  95     <ol>
  96     <li><a href="#updocs">Update Documentation</a></li>
  97     <li><a href="#tag">Tag the LLVM Release Branch</a></li>
  98     <li><a href="#updemo">Update the LLVM Demo Page</a></li>
  99     <li><a href="#webupdates">Update the LLVM Website</a></li>
 100     <li><a href="#announce">Announce the Release</a></li>
 101     </ol>
 102
 103   </ol>
 104 </div>
 105
 106 <!-- ======================================================================= -->
 107 <div class="doc_subsection"><a name="release-admin">
 108 Release Administrative Tasks</a></div>
 109
 110 <div class="doc_text">
 111 This section describes a few administrative tasks that need to be done for the
 112 release process to begin. Specifically, it involves creating the release branch,
 113  resetting version numbers, and creating the release tarballs for the release
 114  team to begin testing.
 115 </div>
 116
 117 <!-- ======================================================================= -->
 118 <div class="doc_subsubsection"><a name="branch">Create Release Branch</a></div>
 119 <div class="doc_text">
 120 <p>Branch the Subversion HEAD using the following procedure:</p>
 121   <ol>
 122     <li>
 123     <p>Verify that the current Subversion HEAD is in decent shape by examining
 124     nightly tester or buildbot results.</p></li>
 125     <li>
 126     <p>Request all developers to refrain from committing. Offenders get commit
 127     rights taken away (temporarily).</p></li>
 128   <li>
 129   <p> Create the release branch for <tt>llvm</tt>, <tt>llvm-gcc4.2</tt>,
 130   <tt>clang</tt>, and the <tt>test-suite</tt>. The branch name will be
 131   <tt>release_XX</tt>,where <tt>XX</tt> is the major and minor release numbers.
 132   <tt>Clang</tt> will have a different release number than <tt>llvm</tt>/
 133   <tt>llvm-gcc4</tt> since its first release was years later
 134   (still deciding if this will be true or not). These branches
 135   can be created without checking out anything from subversion.
 136   </p>
 137
 138   <div class="doc_code">
 139 <pre>
 140 svn copy https://llvm.org/svn/llvm-project/llvm/trunk \
 141          https://llvm.org/svn/llvm-project/llvm/branches/release_<i>XX</i>
 142 svn copy https://llvm.org/svn/llvm-project/llvm-gcc-4.2/trunk \
 143          https://llvm.org/svn/llvm-project/llvm-gcc-4.2/branches/release_<i>XX</i>
 144 svn copy https://llvm.org/svn/llvm-project/test-suite/trunk \
 145          https://llvm.org/svn/llvm-project/test-suite/branches/release_<i>XX</i>
 146 svn copy https://llvm.org/svn/llvm-project/cfe/trunk \
 147          https://llvm.org/svn/llvm-project/cfe/branches/release_<i>XX</i>
 148 </pre>
 149   </div>
 150
 151   <li>
 152     <p>Advise developers they can work on Subversion HEAD again.</p></li>
 153
 154   <li>
 155     <p>The Release Manager should switch to the release branch (as all changes
 156     to the release will now be done in the branch).  The easiest way to do this
 157     is to grab another working copy using the following commands:</p>
 158
 159 <div class="doc_code">
 160 <pre>
 161 svn co https://llvm.org/svn/llvm-project/llvm/branches/release_<i>XX</i>
 162 svn co https://llvm.org/svn/llvm-project/llvm-gcc-4.2/branches/release_<i>XX</i>
 163 svn co https://llvm.org/svn/llvm-project/test-suite/branches/release_<i>XX</i>
 164 svn co https://llvm.org/svn/llvm-project/cfe/branches/release_<i>XX</i>
 165 </pre>
 166 </div></li>
 167
 168   </ol>
 169 </div>
 170
 171 <!-- ======================================================================= -->
 172 <div class="doc_subsubsection"><a name="verchanges">Update LLVM Version</a></div>
 173 <div class="doc_text">
 174   <p>
 175   After creating the LLVM release branch, update the release branches'
 176   autoconf/configure.ac version from X.Xsvn to just X.X. Update it on mainline
 177   as well to be the next version (X.X+1svn). Regenerated the configure script
 178   for both. This must be done for both <tt>llvm</tt> and the
 179   <tt>test-suite</tt>.
 180   </p>
 181   <p>FIXME: Add a note about <tt>clang</tt>.</p>
 182   <p>In addition, the version number of all the Bugzilla components must be
 183   updated for the next release.
 184   </p>
 185 </div>
 186
 187 <!-- ======================================================================= -->
 188 <div class="doc_subsubsection"><a name="dist">Build the LLVM Source Distributions</a></div>
 189 <div class="doc_text">
 190   <p>
 191   Create source distributions for <tt>LLVM</tt>, <tt>LLVM-GCC</tt>,
 192   <tt>clang</tt>, and the llvm <tt>test-suite</tt> by exporting the source from
 193   Subversion and archiving it.  This can be done with the following commands:
 194   </p>
 195
 196 <div class="doc_code">
 197 <pre>
 198 svn export https://llvm.org/svn/llvm-project/llvm/branches/release_<i>XX</i> llvm-X.X
 199 svn export https://llvm.org/svn/llvm-project/llvm-gcc-4.2/branches/release_<i>XX</i> llvm-gcc4.2-X.X.source
 200 svn export https://llvm.org/svn/llvm-project/test-suite/branches/release_<i>XX</i> llvm-test-X.X
 201 svn export https://llvm.org/svn/llvm-project/cfe/branches/release_<i>XX</i> clang-X.X
 202 tar -czvf - llvm-X.X          | gzip &gt; llvm-X.X.tar.gz
 203 tar -czvf - llvm-test-X.X     | gzip &gt; llvm-test-X.X.tar.gz
 204 tar -czvf - llvm-gcc4.2-X.X.source | gzip &gt; llvm-gcc-4.2-X.X.source.tar.gz
 205 tar -czvf - clang-X.X | gzip &gt; clang-X.X.tar.gz
 206 </pre>
 207 </div>
 208 </div>
 209
 210 <!-- ======================================================================= -->
 211 <div class="doc_subsection"><a name="release-build">
 212 Building the Release</a></div>
 213
 214 <div class="doc_text">
 215 The build of <tt>llvm</tt>, <tt>llvm-gcc</tt>, and <tt>clang</tt> must be free
 216 of errors and warnings in both debug, release, and release-asserts builds.
 217 If all builds are clean, then the release passes build qualification.
 218
 219 <ol>
 220 <li>debug: ENABLE_OPTIMIZED=0</li>
 221 <li>release: ENABLE_OPTIMIZED=1</li>
 222 <li>release-asserts: ENABLE_OPTIMIZED=1 DISABLE_ASSERTIONS=1</li>
 223 </ol>
 224 </div>
 225
 226 <!-- ======================================================================= -->
 227 <div class="doc_subsubsection"><a name="build">Build LLVM</a></div>
 228 <div class="doc_text">
 229   <p>
 230   Build both debug, release (optimized), and release-asserts versions of
 231   LLVM on all supported platforms. Direction to build llvm are
 232   <a href="http://llvm.org/docs/GettingStarted.html#quickstart">here</a>.
 233   </p>
 234 </div>
 235
 236 <!-- ======================================================================= -->
 237 <div class="doc_subsubsection"><a name="llvmgccbin">Build the LLVM GCC Binary Distribution</a></div>
 238 <div class="doc_text">
 239   <p>
 240   Creating the LLVM GCC binary distribution (release/optimized) requires
 241   performing the following steps for each supported platform:
 242   </p>
 243
 244   <ol>
 245     <li>
 246     Build the LLVM GCC front-end by following the directions in the README.LLVM
 247     file. The frontend must be compiled with c, c++, objc (mac only),
 248     objc++ (mac only) and fortran support. </li>
 249     <li>Please boostrap as well.</li>
 250     <li>Be sure to build with LLVM_VERSION_INFO=X.X, where X is the major and
 251     minor release numbers.
 252     </li>
 253
 254     <li>
 255     Copy the installation directory to a directory named for the specific target.
 256     For example on Red Hat Enterprise Linux, the directory would be named
 257     <tt>llvm-gcc4.2-2.6-x86-linux-RHEL4</tt>. Archive and compress the new directory.
 258     </li>
 259   </ol>
 260 </div>
 261
 262 <!-- ======================================================================= -->
 263 <div class="doc_subsubsection"><a name="clangbin">Build Clang
 264 Binary Distribution</a></div>
 265 <div class="doc_text">
 266   <p>
 267   Creating the Clang binary distribution (debug/release/release-asserts) requires
 268   performing the following steps for each supported platform:
 269   </p>
 270
 271   <ol>
 272     <li>
 273     Build clang according to the directions
 274     <a href="http://clang.llvm.org/get_started.html">here</a>.
 275     </li>
 276
 277     <li>Build both a debug and release version of clang, but the binary
 278     will be a release build.</lI>
 279
 280     <li>
 281     Package clang (details to follow).
 282     </li>
 283   </ol>
 284 </div>
 285
 286
 287 <!-- ======================================================================= -->
 288 <div class="doc_subsubsection"><a name="target-build">Target Specific Build
 289 Details</a></div>
 290 <div class="doc_text">
 291   <p>
 292   The table below specifies which compilers are used for each arch/os combination
 293   when qualifying the build of <tt>llvm</tt>, <tt>llvm-gcc</tt>, <tt>clang.
 294   </tt></p>
 295
 296   <p>
 297   <table>
 298   <tr><th>Architecture</th><th>OS</th><th>compiler</th></tr>
 299   <tr><td>x86-32</td><td>Mac OS 10.5</td><td>gcc 4.0.1</td></tr>
 300   <tr><td>x86-32</td><td>Linux</td><td>gcc 4.2.X, gcc 4.3.X</td></tr>
 301   <tr><td>x86-32</td><td>FreeBSD</td><td>gcc 4.2.X</td></tr>
 302    <tr><td>x86-32</td><td>mingw</td><td>gcc 3.4.5</td></tr>
 303   <tr><td>x86-64</td><td>Mac OS 10.5</td><td>gcc 4.0.1</td></tr>
 304   <tr><td>x86-64</td><td>Linux</td><td>gcc 4.2.X, gcc 4.3.X</td></tr>
 305   <tr><td>x86-64</td><td>FreeBSD</td><td>gcc 4.2.X</td></tr>
 306
 307   </table>
 308   </p>
 309
 310 </div>
 311
 312
 313 <!-- ======================================================================= -->
 314 <div class="doc_subsection"><a name="release-qualify">
 315 Building the Release</a></div>
 316
 317 <div class="doc_text">
 318  A release is qualified when it has no regressions from the previous
 319  release (or baseline). Regressions are related to correctness only and not
 320  performance at this time. <b>Regressions are new failures in the set of tests that
 321  are used to qualify each product and only include things on the list.
 322  Ultimately, there is no end to the number of possible bugs in a release.  We
 323  need a very concrete and definitive release criteria that ensures we have
 324  monotonically improving quality on some metric.  The metric we use is
 325  described below.  This doesn't mean that we don't care about other things,
 326  but this are things that must be satisfied before a release can go out</b>
 327 </div>
 328
 329
 330 <!-- ======================================================================= -->
 331 <div class="doc_subsubsection"><a name="llvm-qualify">Qualify LLVM</a></div>
 332 <div class="doc_text">
 333   <p>
 334   LLVM is qualified when it has a clean dejagnu test run without a frontend and
 335   it has no regressions when using either <tt>llvm-gcc</tt> or <tt>clang</tt>
 336   with the <tt>test-suite</tt> from the previous release.
 337 </p>
 338 </div>
 339
 340 <!-- ======================================================================= -->
 341 <div class="doc_subsubsection"><a name="llvmgcc-qualify">Qualify LLVM-GCC</a></div>
 342 <div class="doc_text">
 343   <p>
 344   <tt>LLVM-GCC</tt> is qualified when front-end specific tests in the
 345   <tt>llvm</tt> dejagnu test suite all pass and there are no regressions in
 346   the <tt>test-suite</tt>.</p>
 347   <p>We do not use the gcc dejagnu test suite as release criteria.</p>
 348 </div>
 349
 350 <!-- ======================================================================= -->
 351 <div class="doc_subsubsection"><a name="clang-qualify">Qualify Clang</a></div>
 352 <div class="doc_text">
 353     <tt>Clang</tt> is qualified when front-end specific tests in the
 354   <tt>llvm</tt> dejagnu test suite all pass, clang's own test suite passes
 355   cleanly, and there are no regressions in the <tt>test-suite</tt>.</p>
 356 </div>
 357
 358 <!-- ======================================================================= -->
 359 <div class="doc_subsubsection"><a name="targets">Specific Target
 360 Qualification Details</a></div>
 361 <div class="doc_text">
 362   <p><table>
 363   <tr><th>Architecture</th><th>OS</th><th>llvm-gcc baseline</th><th>clang baseline
 364   </th><th>tests</th></tr>
 365   <tr><td>x86-32</td><td>Mac OS 10.5</td><td>last release</td><td>none</td><td>llvm dejagnu, clang tests, test-suite (including spec)</td></tr>
 366   <tr><td>x86-32</td><td>Linux</td><td>last release</td><td>none</td><td>llvm dejagnu, clang tests, test-suite (including spec)</td></tr>
 367   <tr><td>x86-32</td><td>FreeBSD</td><td>none</td><td>none</td><td>llvm dejagnu, clang tests, test-suite</td></tr>
 368   <tr><td>x86-32</td><td>mingw</td><td>last release</td><td>none</td><td>QT</td></tr>
 369   <tr><td>x86-64</td><td>Mac OS 10.5</td><td>last release</td><td>none</td><td>llvm dejagnu, clang tests, test-suite (including spec)</td></tr>
 370   <tr><td>x86-64</td><td>Linux</td><td>last release</td><td>none</td><td>llvm dejagnu, clang tests, test-suite (including spec)</td></tr>
 371   <tr><td>x86-64</td><td>FreeBSD</td><td>none</td><td>none</td><td>llvm dejagnu, clang tests, test-suite</td></tr>
 372   </table></p>
 373 </div>
 374
 375 <!-- ======================================================================= -->
 376 <div class="doc_subsection"><a name="commTest">Community Testing</a></div>
 377 <div class="doc_text">
 378   <p>
 379   Once all testing has been completed and appropriate bugs filed, the pre-release
 380   tar balls may be put on the website and the LLVM community is notified. Ask that
 381   all LLVM developers test the release in 2 ways:</p>
 382   <ol>
 383   <li>Download llvm-X.X, llvm-test-X.X, and the appropriate llvm-gcc4
 384   and/or clang binary. Build LLVM.
 385   Run "make check" and the full llvm-test suite (make TEST=nightly report).</li>
 386   <li>Download llvm-X.X, llvm-test-X.X, and the llvm-gcc4 and/or clang source.
 387   Compile everything. Run "make check" and the full llvm-test suite (make TEST=nightly
 388   report).</li>
 389   </ol>
 390   <p>Ask LLVM developers to submit the report and make check results to the list.
 391   Attempt to verify that there are no regressions from the previous release.
 392   The results are not used to qualify a release, but to spot other potential
 393   problems. For unsupported targets, verify that make check at least is
 394   clean.</p>
 395
 396   <p>During the first round of testing time,
 397   all regressions must be fixed before the second pre-release is created.</p>
 398
 399   <p>If this is the second round of testing, this is only to ensure the bug
 400   fixes previously merged in have not created new major problems. This is not
 401   the time to solve additional and unrelated bugs. If no patches are merged in,
 402   the release is determined to be ready and the release manager may move onto
 403   the next step.
 404   </p>
 405 </div>
 406
 407 <!-- ======================================================================= -->
 408 <div class="doc_subsection"><a name="release-patch">Release Patch Rules
 409 </a></div>
 410 <div class="doc_text">
 411   <p>
 412   Below are the rules regarding patching the release branch.</p>
 413   <p>
 414   <li>Patches applied to the release branch are only applied by the release
 415   manager.</li>
 416   <li>During the first round of testing, patches that fix regressions or that
 417   are small and relatively risk free (verified by the appropriate code owner)
 418   are applied to the branch. Code owners are asked to be very conservative in
 419   approving patches for the branch and we reserve the right to reject any patch
 420   that does not fix a regression as previously defined.</li>
 421   <li>During the remaining rounds of testing, only patches that fix regressions
 422   may be applied.</li>
 423
 424   </p>
 425 </div>
 426
 427
 428 <!-- ======================================================================= -->
 429 <div class="doc_subsection"><a name="release-final">Release Final Tasks
 430 </a></div>
 431 <div class="doc_text">
 432   <p>
 433   The final stages of the release process involving taging the release branch,
 434   updating documentation that refers to the release, and updating the demo
 435   page.</p>
 436   <p>FIXME: Add a note if anything needs to be done to the clang website.
 437   Eventually the websites will be merged hopefully.</p>
 438 </div>
 439
 440
 441 <!-- ======================================================================= -->
 442 <div class="doc_subsubsection"><a name="updocs">Update Documentation</a></div>
 443 <div class="doc_text">
 444   <p>
 445   Review the documentation and ensure that it is up to date.  The Release Notes
 446   must be updated to reflect bug fixes, new known issues, and changes in the
 447   list of supported platforms.  The Getting Started Guide should be updated to
 448   reflect the new release version number tag avaiable from Subversion and
 449   changes in basic system requirements. Merge both changes from mainline into
 450   the release branch.
 451   </p>
 452 </div>
 453
 454 <!-- ======================================================================= -->
 455 <div class="doc_subsubsection"><a name="tag">Tag the Release Branch</a></div>
 456 <div class="doc_text">
 457   <p>Tag the release branch using the following procedure:</p>
 458 <div class="doc_code">
 459 <pre>
 460 svn copy https://llvm.org/svn/llvm-project/llvm/branches/release_XX \
 461          https://llvm.org/svn/llvm-project/llvm/tags/RELEASE_<i>XX</i>
 462 svn copy https://llvm.org/svn/llvm-project/llvm-gcc-4.2/branches/release_XX \
 463          https://llvm.org/svn/llvm-project/llvm-gcc-4.2/tags/RELEASE_<i>XX</i>
 464 svn copy https://llvm.org/svn/llvm-project/test-suite/branches/release_XX \
 465          https://llvm.org/svn/llvm-project/test-suite/tags/RELEASE_<i>XX</i>
 466 </pre>
 467 </div>
 468 </div>
 469
 470
 471
 472 <!-- ======================================================================= -->
 473 <div class="doc_subsection"><a name="updemo">Update the LLVM Demo Page</a></div>
 474 <div class="doc_text">
 475   <p>
 476   The LLVM demo page must be updated to use the new release. This consists of
 477   using the llvm-gcc binary and building LLVM. Update the website demo page
 478   configuration to use the new release.</p>
 479 </div>
 480
 481 <!-- ======================================================================= -->
 482 <div class="doc_subsubsection"><a name="webupdates">Update the LLVM Website</a></div>
 483 <div class="doc_text">
 484   <p>
 485   The website must be updated before the release announcement is sent out. Here is
 486   what to do:</p>
 487   <ol>
 488   <li> Check out the <tt>website</tt> module from CVS. </li>
 489   <li> Create a new subdirectory X.X in the releases directory. </li>
 490   <li> Commit the <tt>llvm</tt>, <tt>test-suite</tt>, <tt>llvm-gcc</tt> source,
 491   <tt>clang source</tt>, <tt>clang binaries</tt>,
 492   and <tt>llvm-gcc</tt> binaries in this new directory. </li>
 493   <li> Copy and commit the <tt>llvm/docs</tt> and <tt>LICENSE.txt</tt>
 494   files into this new directory. The docs should be built with BUILD_FOR_WEBSITE=1.</li>
 495   <li> Commit the index.html to the release/X.X directory to redirect (use from previous
 496   release. </li>
 497   <li> Update the <tt>releases/download.html</tt> file with the new release. </li>
 498   <li>Update the <tt>releases/index.html</tt> with the new release and link to
 499   release documentation.</li>
 500   <li> Finally, update the main page (<tt>index.html</tt> and sidebar) to
 501   point to the new release and release announcement. Make sure this all gets
 502   commited back into Subversion.</li>
 503   </ol>
 504 </div>
 505
 506 <!-- ======================================================================= -->
 507 <div class="doc_subsubsection"><a name="announce">Announce the Release</a></div>
 508 <div class="doc_text">
 509   <p>Have Chris send out the release announcement when everything is finished.</p>
 510 </div>
 511
 512 <!-- *********************************************************************** -->
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 521   Last modified: $Date$
 522 </address>
 523 </body>
 524 </html>