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1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
2                      "http://www.w3.org/TR/html4/strict.dtd">
3<html>
4<head>
5  <title>How To Release LLVM To The Public</title>
6  <link rel="stylesheet" href="llvm.css" type="text/css">
7</head>
8<body>
9
10<h1>How To Release LLVM To The Public</h1>
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>, &amp;
21  <a href="mailto:wendling@apple.com">Bill Wendling</a>
22  </p>
23</div>
24
25<!-- *********************************************************************** -->
26<h2><a name="introduction">Introduction</a></h2>
27<!-- *********************************************************************** -->
28
29<div>
30
31<p>This document contains information about successfully releasing LLVM &mdash;
32   including subprojects: e.g., <tt>clang</tt> and <tt>dragonegg</tt> &mdash; to
33   the public. It is the Release Manager's responsibility to ensure that a high
34   quality build of LLVM is released.</p>
35
36</div>
37
38<!-- *********************************************************************** -->
39<h2><a name="process">Release Timeline</a></h2>
40<!-- *********************************************************************** -->
41<div>
42
43<p>LLVM is released on a time based schedule &mdash; roughly every 6 months. We
44   do not normally have dot releases because of the nature of LLVM's incremental
45   development philosophy. That said, the only thing preventing dot releases for
46   critical bug fixes from happening is a lack of resources &mdash; testers,
47   machines, time, etc. And, because of the high quality we desire for LLVM
48   releases, we cannot allow for a truncated form of release qualification.</p>
49
50<p>The release process is roughly as follows:</p>
51
52<ul>
53  <li><p>Set code freeze and branch creation date for 6 months after last code
54      freeze date. Announce release schedule to the LLVM community and update
55      the website.</p></li>
56
57  <li><p>Create release branch and begin release process.</p></li>
58
59  <li><p>Send out release candidate sources for first round of testing. Testing
60      lasts 7-10 days. During the first round of testing, any regressions found
61      should be fixed. Patches are merged from mainline into the release
62      branch. Also, all features need to be completed during this time. Any
63      features not completed at the end of the first round of testing will be
64      removed or disabled for the release.</p></li>
65
66  <li><p>Generate and send out the second release candidate sources. Only
67      <em>critial</em> bugs found during this testing phase will be fixed. Any
68      bugs introduced by merged patches will be fixed. If so a third round of
69      testing is needed.</p></li>
70
71  <li><p>The release notes are updated.</p></li>
72
73  <li><p>Finally, release!</p></li>
74</ul>
75
76</div>
77
78<!-- *********************************************************************** -->
79<h2><a name="process">Release Process</a></h2>
80<!-- *********************************************************************** -->
81
82<div>
83
84<ol>
85  <li><a href="#release-admin">Release Administrative Tasks</a>
86  <ol>
87    <li><a href="#branch">Create Release Branch</a></li>
88    <li><a href="#verchanges">Update Version Numbers</a></li>
89  </ol>
90  </li>
91  <li><a href="#release-build">Building the Release</a>
92  <ol>
93    <li><a href="#dist">Build the LLVM Source Distributions</a></li>
94    <li><a href="#build">Build LLVM</a></li>
95    <li><a href="#clangbin">Build the Clang Binary Distribution</a></li>
96    <li><a href="#target-build">Target Specific Build Details</a></li>
97  </ol>
98  </li>
99  <li><a href="#release-qualify">Release Qualification Criteria</a>
100  <ol>
101    <li><a href="#llvm-qualify">Qualify LLVM</a></li>
102    <li><a href="#clang-qualify">Qualify Clang</a></li>
103    <li><a href="#targets">Specific Target Qualification Details</a></li>
104  </ol>
105  </li>
106
107  <li><a href="#commTest">Community Testing</a></li>
108  <li><a href="#release-patch">Release Patch Rules</a></li>
109  <li><a href="#release-final">Release final tasks</a>
110  <ol>
111    <li><a href="#updocs">Update Documentation</a></li>
112    <li><a href="#tag">Tag the LLVM Final Release</a></li>
113    <li><a href="#updemo">Update the LLVM Demo Page</a></li>
114    <li><a href="#webupdates">Update the LLVM Website</a></li>
115    <li><a href="#announce">Announce the Release</a></li>
116  </ol>
117  </li>
118</ol>
119
120<!-- ======================================================================= -->
121<h3><a name="release-admin">Release Administrative Tasks</a></h3>
122
123<div>
124
125<p>This section describes a few administrative tasks that need to be done for
126   the release process to begin. Specifically, it involves:</p>
127
128<ul>
129  <li>Creating the release branch,</li>
130  <li>Setting version numbers, and</li>
131  <li>Tagging release candidates for the release team to begin testing</li>
132</ul>
133
134<!-- ======================================================================= -->
135<h4><a name="branch">Create Release Branch</a></h4>
136
137<div>
138
139<p>Branch the Subversion trunk using the following procedure:</p>
140
141<ol>
142  <li><p>Remind developers that the release branching is imminent and to refrain
143      from committing patches that might break the build. E.g., new features,
144      large patches for works in progress, an overhaul of the type system, an
145      exciting new TableGen feature, etc.</p></li>
146
147  <li><p>Verify that the current Subversion trunk is in decent shape by
148      examining nightly tester and buildbot results.</p></li>
149
150  <li><p>Create the release branch for <tt>llvm</tt>, <tt>clang</tt>,
151      the <tt>test-suite</tt>, and <tt>dragonegg</tt> from the last known good
152      revision. The branch's name is <tt>release_<i>XY</i></tt>,
153      where <tt>X</tt> is the major and <tt>Y</tt> the minor release
154      numbers. The branches should be created using the following commands:</p>
155
156<div class="doc_code">
157<pre>
158$ svn copy https://llvm.org/svn/llvm-project/llvm/trunk \
159           https://llvm.org/svn/llvm-project/llvm/branches/release_<i>XY</i>
160
161$ svn copy https://llvm.org/svn/llvm-project/cfe/trunk \
162           https://llvm.org/svn/llvm-project/cfe/branches/release_<i>XY</i>
163
164$ svn copy https://llvm.org/svn/llvm-project/dragonegg/trunk \
165           https://llvm.org/svn/llvm-project/dragonegg/branches/release_<i>XY</i>
166
167$ svn copy https://llvm.org/svn/llvm-project/test-suite/trunk \
168           https://llvm.org/svn/llvm-project/test-suite/branches/release_<i>XY</i>
169</pre>
170</div></li>
171
172  <li><p>Advise developers that they may now check their patches into the
173      Subversion tree again.</p></li>
174
175  <li><p>The Release Manager should switch to the release branch, because all
176      changes to the release will now be done in the branch. The easiest way to
177      do this is to grab a working copy using the following commands:</p>
178
179<div class="doc_code">
180<pre>
181$ svn co https://llvm.org/svn/llvm-project/llvm/branches/release_<i>XY</i> llvm-<i>X.Y</i>
182
183$ svn co https://llvm.org/svn/llvm-project/cfe/branches/release_<i>XY</i> clang-<i>X.Y</i>
184
185$ svn co https://llvm.org/svn/llvm-project/dragonegg/branches/release_<i>XY</i> dragonegg-<i>X.Y</i>
186
187$ svn co https://llvm.org/svn/llvm-project/test-suite/branches/release_<i>XY</i> test-suite-<i>X.Y</i>
188</pre>
189</div></li>
190</ol>
191
192</div>
193
194<!-- ======================================================================= -->
195<h4><a name="verchanges">Update LLVM Version</a></h4>
196
197<div>
198
199<p>After creating the LLVM release branch, update the release branches'
200   <tt>autoconf</tt> and <tt>configure.ac</tt> versions from '<tt>X.Ysvn</tt>'
201   to '<tt>X.Y</tt>'. Update it on mainline as well to be the next version
202   ('<tt>X.Y+1svn</tt>'). Regenerate the configure scripts for both
203   <tt>llvm</tt> and the <tt>test-suite</tt>.</p>
204
205<p>In addition, the version numbers of all the Bugzilla components must be
206   updated for the next release.</p>
207
208</div>
209
210<!-- ======================================================================= -->
211<h4><a name="dist">Build the LLVM Release Candidates</a></h4>
212
213<div>
214
215<p>Create release candidates for <tt>llvm</tt>, <tt>clang</tt>,
216   <tt>dragonegg</tt>, and the LLVM <tt>test-suite</tt> by tagging the branch
217   with the respective release candidate number. For instance, to
218   create <b>Release Candidate 1</b> you would issue the following commands:</p>
219
220<div class="doc_code">
221<pre>
222$ svn mkdir https://llvm.org/svn/llvm-project/llvm/tags/RELEASE_<i>XY</i>
223$ svn copy https://llvm.org/svn/llvm-project/llvm/branches/release_<i>XY</i> \
224           https://llvm.org/svn/llvm-project/llvm/tags/RELEASE_<i>XY</i>/rc1
225
226$ svn mkdir https://llvm.org/svn/llvm-project/cfe/tags/RELEASE_<i>XY</i>
227$ svn copy https://llvm.org/svn/llvm-project/cfe/branches/release_<i>XY</i> \
228           https://llvm.org/svn/llvm-project/cfe/tags/RELEASE_<i>XY</i>/rc1
229
230$ svn mkdir https://llvm.org/svn/llvm-project/dragonegg/tags/RELEASE_<i>XY</i>
231$ svn copy https://llvm.org/svn/llvm-project/dragonegg/branches/release_<i>XY</i> \
232           https://llvm.org/svn/llvm-project/dragonegg/tags/RELEASE_<i>XY</i>/rc1
233
234$ svn mkdir https://llvm.org/svn/llvm-project/test-suite/tags/RELEASE_<i>XY</i>
235$ svn copy https://llvm.org/svn/llvm-project/test-suite/branches/release_<i>XY</i> \
236           https://llvm.org/svn/llvm-project/test-suite/tags/RELEASE_<i>XY</i>/rc1
237</pre>
238</div>
239
240<p>Similarly, <b>Release Candidate 2</b> would be named <tt>RC2</tt> and so
241   on. This keeps a permanent copy of the release candidate around for people to
242   export and build as they wish. The final released sources will be tagged in
243   the <tt>RELEASE_<i>XY</i></tt> directory as <tt>Final</tt>
244   (c.f. <a href="#tag">Tag the LLVM Final Release</a>).</p>
245
246<p>The Release Manager may supply pre-packaged source tarballs for users. This
247   can be done with the following commands:</p>
248
249<div class="doc_code">
250<pre>
251$ svn export https://llvm.org/svn/llvm-project/llvm/tags/RELEASE_<i>XY</i>/rc1 llvm-<i>X.Y</i>rc1
252$ svn export https://llvm.org/svn/llvm-project/cfe/tags/RELEASE_<i>XY</i>/rc1 clang-<i>X.Y</i>rc1
253$ svn export https://llvm.org/svn/llvm-project/dragonegg/tags/RELEASE_<i>XY</i>/rc1 dragonegg-<i>X.Y</i>rc1
254$ svn export https://llvm.org/svn/llvm-project/test-suite/tags/RELEASE_<i>XY</i>/rc1 llvm-test-<i>X.Y</i>rc1
255
256$ tar -cvf - llvm-<i>X.Y</i>rc1        | gzip &gt; llvm-<i>X.Y</i>rc1.src.tar.gz
257$ tar -cvf - clang-<i>X.Y</i>rc1       | gzip &gt; clang-<i>X.Y</i>rc1.src.tar.gz
258$ tar -cvf - dragonegg-<i>X.Y</i>rc1   | gzip &gt; dragonegg-<i>X.Y</i>rc1.src.tar.gz
259$ tar -cvf - llvm-test-<i>X.Y</i>rc1   | gzip &gt; llvm-test-<i>X.Y</i>rc1.src.tar.gz
260</pre>
261</div>
262
263</div>
264
265</div>
266
267<!-- ======================================================================= -->
268<h3><a name="release-build">Building the Release</a></h3>
269
270<div>
271
272<p>The builds of <tt>llvm</tt>, <tt>clang</tt>, and <tt>dragonegg</tt>
273   <em>must</em> be free of errors and warnings in Debug, Release+Asserts, and
274   Release builds. If all builds are clean, then the release passes Build
275   Qualification.</p>
276
277<p>The <tt>make</tt> options for building the different modes:</p>
278
279<table>
280  <tr><th>Mode</th><th>Options</th></tr>
281  <tr align="left"><td>Debug</td><td><tt>ENABLE_OPTIMIZED=0</tt></td></tr>
282  <tr align="left"><td>Release+Asserts</td><td><tt>ENABLE_OPTIMIZED=1</tt></td></tr>
283  <tr align="left"><td>Release</td><td><tt>ENABLE_OPTIMIZED=1 DISABLE_ASSERTIONS=1</tt></td></tr>
284</table>
285
286<!-- ======================================================================= -->
287<h4><a name="build">Build LLVM</a></h4>
288
289<div>
290
291<p>Build <tt>Debug</tt>, <tt>Release+Asserts</tt>, and <tt>Release</tt> versions
292   of <tt>llvm</tt> on all supported platforms. Directions to build
293   <tt>llvm</tt> are <a href="GettingStarted.html#quickstart">here</a>.</p>
294
295</div>
296
297<!-- ======================================================================= -->
298<h4><a name="clangbin">Build Clang Binary Distribution</a></h4>
299
300<div>
301
302<p>Creating the <tt>clang</tt> binary distribution
303   (Debug/Release+Asserts/Release) requires performing the following steps for
304   each supported platform:</p>
305
306<ol>
307  <li>Build clang according to the directions
308      <a href="http://clang.llvm.org/get_started.html">here</a>.</li>
309
310  <li>Build both a Debug and Release version of clang. The binary will be the
311      Release build.</lI>
312
313  <li>Package <tt>clang</tt> (details to follow).</li>
314</ol>
315
316</div>
317
318<!-- ======================================================================= -->
319<h4><a name="target-build">Target Specific Build Details</a></h4>
320
321<div>
322
323<p>The table below specifies which compilers are used for each Arch/OS
324   combination when qualifying the build of <tt>llvm</tt>, <tt>clang</tt>,
325   and <tt>dragonegg</tt>.</p>
326
327<table>
328  <tr><th>Architecture</th> <th>OS</th>          <th>compiler</th></tr>
329  <tr><td>x86-32</td>       <td>Mac OS 10.5</td> <td>gcc 4.0.1</td></tr>
330  <tr><td>x86-32</td>       <td>Linux</td>       <td>gcc 4.2.X, gcc 4.3.X</td></tr>
331  <tr><td>x86-32</td>       <td>FreeBSD</td>     <td>gcc 4.2.X</td></tr>
332  <tr><td>x86-32</td>       <td>mingw</td>       <td>gcc 3.4.5</td></tr>
333  <tr><td>x86-64</td>       <td>Mac OS 10.5</td> <td>gcc 4.0.1</td></tr>
334  <tr><td>x86-64</td>       <td>Linux</td>       <td>gcc 4.2.X, gcc 4.3.X</td></tr>
335  <tr><td>x86-64</td>       <td>FreeBSD</td>     <td>gcc 4.2.X</td></tr>
336</table>
337
338</div>
339
340</div>
341
342<!-- ======================================================================= -->
343<h3><a name="release-qualify">Building the Release</a></h3>
344
345<div>
346
347<p>A release is qualified when it has no regressions from the previous release
348   (or baseline). Regressions are related to correctness first and performance
349   second. (We may tolerate some minor performance regressions if they are
350   deemed necessary for the general quality of the compiler.)</p>
351
352<p><b>Regressions are new failures in the set of tests that are used to qualify
353   each product and only include things on the list. Every release will have
354   some bugs in it. It is the reality of developing a complex piece of
355   software. We need a very concrete and definitive release criteria that
356   ensures we have monotonically improving quality on some metric. The metric we
357   use is described below. This doesn't mean that we don't care about other
358   criteria, but these are the criteria which we found to be most important and
359   which must be satisfied before a release can go out</b></p>
360
361<!-- ======================================================================= -->
362<h4><a name="llvm-qualify">Qualify LLVM</a></h4>
363
364<div>
365
366<p>LLVM is qualified when it has a clean test run without a front-end. And it
367   has no regressions when using either <tt>clang</tt> or <tt>dragonegg</tt>
368   with the <tt>test-suite</tt> from the previous release.</p>
369
370</div>
371
372<!-- ======================================================================= -->
373<h4><a name="clang-qualify">Qualify Clang</a></h4>
374
375<div>
376
377<p><tt>Clang</tt> is qualified when front-end specific tests in the
378   <tt>llvm</tt> dejagnu test suite all pass, clang's own test suite passes
379   cleanly, and there are no regressions in the <tt>test-suite</tt>.</p>
380
381</div>
382
383<!-- ======================================================================= -->
384<h4><a name="targets">Specific Target Qualification Details</a></h4>
385
386<div>
387
388<table>
389  <tr><th>Architecture</th> <th>OS</th>          <th>clang baseline</th> <th>tests</th></tr>
390  <tr><td>x86-32</td>       <td>Linux</td>       <td>last release</td>   <td>llvm dejagnu, clang tests, test-suite (including spec)</td></tr>
391  <tr><td>x86-32</td>       <td>FreeBSD</td>     <td>last release</td>   <td>llvm dejagnu, clang tests, test-suite</td></tr>
392  <tr><td>x86-32</td>       <td>mingw</td>       <td>none</td>           <td>QT</td></tr>
393  <tr><td>x86-64</td>       <td>Mac OS 10.X</td> <td>last release</td>   <td>llvm dejagnu, clang tests, test-suite (including spec)</td></tr>
394  <tr><td>x86-64</td>       <td>Linux</td>       <td>last release</td>   <td>llvm dejagnu, clang tests, test-suite (including spec)</td></tr>
395  <tr><td>x86-64</td>       <td>FreeBSD</td>     <td>last release</td>   <td>llvm dejagnu, clang tests, test-suite</td></tr>
396</table>
397
398</div>
399
400</div>
401
402<!-- ======================================================================= -->
403<h3><a name="commTest">Community Testing</a></h3>
404<div>
405
406<p>Once all testing has been completed and appropriate bugs filed, the release
407   candidate tarballs are put on the website and the LLVM community is
408   notified. Ask that all LLVM developers test the release in 2 ways:</p>
409
410<ol>
411  <li>Download <tt>llvm-<i>X.Y</i></tt>, <tt>llvm-test-<i>X.Y</i></tt>, and the
412      appropriate <tt>clang</tt> binary. Build LLVM. Run <tt>make check</tt> and
413      the full LLVM test suite (<tt>make TEST=nightly report</tt>).</li>
414
415  <li>Download <tt>llvm-<i>X.Y</i></tt>, <tt>llvm-test-<i>X.Y</i></tt>, and the
416      <tt>clang</tt> sources. Compile everything. Run <tt>make check</tt> and
417      the full LLVM test suite (<tt>make TEST=nightly report</tt>).</li>
418</ol>
419
420<p>Ask LLVM developers to submit the test suite report and <tt>make check</tt>
421   results to the list. Verify that there are no regressions from the previous
422   release. The results are not used to qualify a release, but to spot other
423   potential problems. For unsupported targets, verify that <tt>make check</tt>
424   is at least clean.</p>
425
426<p>During the first round of testing, all regressions must be fixed before the
427   second release candidate is tagged.</p>
428
429<p>If this is the second round of testing, the testing is only to ensure that
430   bug fixes previously merged in have not created new major problems. <i>This
431   is not the time to solve additional and unrelated bugs!</i> If no patches are
432   merged in, the release is determined to be ready and the release manager may
433   move onto the next stage.</p>
434
435</div>
436
437<!-- ======================================================================= -->
438<h3><a name="release-patch">Release Patch Rules</a></h3>
439
440<div>
441
442<p>Below are the rules regarding patching the release branch:</p>
443
444<ol>
445  <li><p>Patches applied to the release branch may only be applied by the
446      release manager.</p></li>
447
448  <li><p>During the first round of testing, patches that fix regressions or that
449      are small and relatively risk free (verified by the appropriate code
450      owner) are applied to the branch. Code owners are asked to be very
451      conservative in approving patches for the branch. We reserve the right to
452      reject any patch that does not fix a regression as previously
453      defined.</p></li>
454
455  <li><p>During the remaining rounds of testing, only patches that fix critical
456      regressions may be applied.</p></li>
457</ol>
458
459</div>
460
461<!-- ======================================================================= -->
462<h3><a name="release-final">Release Final Tasks</a></h3>
463
464<div>
465
466<p>The final stages of the release process involves tagging the "final" release
467   branch, updating documentation that refers to the release, and updating the
468   demo page.</p>
469
470<!-- ======================================================================= -->
471<h4><a name="updocs">Update Documentation</a></h4>
472
473<div>
474
475<p>Review the documentation and ensure that it is up to date. The "Release
476   Notes" must be updated to reflect new features, bug fixes, new known issues,
477   and changes in the list of supported platforms. The "Getting Started Guide"
478   should be updated to reflect the new release version number tag avaiable from
479   Subversion and changes in basic system requirements. Merge both changes from
480   mainline into the release branch.</p>
481
482</div>
483
484<!-- ======================================================================= -->
485<h4><a name="tag">Tag the LLVM Final Release</a></h4>
486
487<div>
488
489<p>Tag the final release sources using the following procedure:</p>
490
491<div class="doc_code">
492<pre>
493$ svn copy https://llvm.org/svn/llvm-project/llvm/branches/release_XY \
494           https://llvm.org/svn/llvm-project/llvm/tags/RELEASE_<i>XY</i>/Final
495
496$ svn copy https://llvm.org/svn/llvm-project/cfe/branches/release_XY \
497           https://llvm.org/svn/llvm-project/cfe/tags/RELEASE_<i>XY</i>/Final
498
499$ svn copy https://llvm.org/svn/llvm-project/dragonegg/branches/release_XY \
500           https://llvm.org/svn/llvm-project/dragonegg/tags/RELEASE_<i>XY</i>/Final
501
502$ svn copy https://llvm.org/svn/llvm-project/test-suite/branches/release_XY \
503           https://llvm.org/svn/llvm-project/test-suite/tags/RELEASE_<i>XY</i>/Final
504</pre>
505</div>
506
507</div>
508
509</div>
510
511<!-- ======================================================================= -->
512<h3><a name="updemo">Update the LLVM Demo Page</a></h3>
513
514<div>
515
516<p>The LLVM demo page must be updated to use the new release. This consists of
517   using the new <tt>clang</tt> binary and building LLVM.</p>
518
519<!-- ======================================================================= -->
520<h4><a name="webupdates">Update the LLVM Website</a></h4>
521
522<div>
523
524<p>The website must be updated before the release announcement is sent out. Here
525   is what to do:</p>
526
527<ol>
528  <li>Check out the <tt>www</tt> module from Subversion.</li>
529
530  <li>Create a new subdirectory <tt>X.Y</tt> in the releases directory.</li>
531
532  <li>Commit the <tt>llvm</tt>, <tt>test-suite</tt>, <tt>clang</tt> source,
533      <tt>clang binaries</tt>, <tt>dragonegg</tt> source, and <tt>dragonegg</tt>
534      binaries in this new directory.</li>
535
536  <li>Copy and commit the <tt>llvm/docs</tt> and <tt>LICENSE.txt</tt> files
537      into this new directory. The docs should be built with
538      <tt>BUILD_FOR_WEBSITE=1</tt>.</li>
539
540  <li>Commit the <tt>index.html</tt> to the <tt>release/X.Y</tt> directory to
541      redirect (use from previous release.</li>
542
543  <li>Update the <tt>releases/download.html</tt> file with the new release.</li>
544
545  <li>Update the <tt>releases/index.html</tt> with the new release and link to
546      release documentation.</li>
547
548  <li>Finally, update the main page (<tt>index.html</tt> and sidebar) to point
549      to the new release and release announcement. Make sure this all gets
550      committed back into Subversion.</li>
551</ol>
552
553</div>
554
555<!-- ======================================================================= -->
556<h4><a name="announce">Announce the Release</a></h4>
557
558<div>
559
560<p>Have Chris send out the release announcement when everything is finished.</p>
561
562</div>
563
564</div>
565
566</div>
567
568<!-- *********************************************************************** -->
569<hr>
570<address>
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572  src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS"></a>
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575  <a href="http://llvm.org/">The LLVM Compiler Infrastructure</a>
576  <br>
577  Last modified: $Date: 2011-10-17 16:32:14 -0400 (Mon, 17 Oct 2011) $
578</address>
579</body>
580</html>
581