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<title>LLVM Developer Policy</title>
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<link rel="stylesheet" href="llvm.css" type="text/css">
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</head>
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<body>
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<div class="doc_title">LLVM Developer Policy</div>
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<ol>
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<li><a href="#introduction">Introduction</a></li>
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<li><a href="#policies">Developer Policies</a>
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<ol>
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<li><a href="#informed">Stay Informed</a></li>
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<li><a href="#patches">Making a Patch</a></li>
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<li><a href="#reviews">Code Reviews</a></li>
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<li><a href="#testcases">Test Cases</a></li>
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<li><a href="#quality">Quality</a></li>
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<li><a href="#commitaccess">Obtaining Commit Access</a></li>
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<li><a href="#newwork">Making a Major Change</a></li>
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<li><a href="#incremental">Incremental Development</a></li>
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<li><a href="#attribution">Attribution of Changes</a></li>
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</ol></li>
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<li><a href="#clp">Copyright, License, and Patents</a>
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<ol>
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<li><a href="#copyright">Copyright</a></li>
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<li><a href="#license">License</a></li>
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<li><a href="#patents">Patents</a></li>
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<li><a href="#devagree">Developer Agreements</a></li>
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</ol></li>
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</ol>
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<div class="doc_author">Written by the LLVM Oversight Team</div>
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<!--=========================================================================-->
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<div class="doc_section"><a name="introduction">Introduction</a></div>
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<!--=========================================================================-->
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<div class="doc_text">
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<p>This document contains the LLVM Developer Policy which defines the
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project's policy towards developers and their contributions. The intent of
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this policy is to eliminate mis-communication, rework, and confusion that
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might arise from the distributed nature of LLVM's development. By stating
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the policy in clear terms, we hope each developer can know ahead of time
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what to expect when making LLVM contributions.</p>
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<p>This policy is also designed to accomplish the following objectives:</p>
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<ol>
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<li>Attract both users and developers to the LLVM project.</li>
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<li>Make life as simple and easy for contributors as possible.</li>
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<li>Keep the top of tree CVS/SVN trees as stable as possible.</li>
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</ol>
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2007-02-19 06:57:16 +00:00
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<p>This policy is aimed at frequent contributors to LLVM. People interested in
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contributing one-off patches can do so in an informal way by sending them to
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the <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits">
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llvm-commits mailing list</a> and engaging another developer to see it through
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the process.</p>
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</div>
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<!--=========================================================================-->
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<div class="doc_section"><a name="policies">Developer Policies</a></div>
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<!--=========================================================================-->
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<div class="doc_text">
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<p>This section contains policies that pertain to frequent LLVM
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developers. We always welcome <a href="#patches">one-off patches</a> from
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people who do not routinely contribute to LLVM, but we expect more from
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frequent contributors to keep the system as efficient as possible for
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everyone.
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Frequent LLVM contributors are expected to meet the following requirements in
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order for LLVM to maintain a high standard of quality.<p>
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</div>
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<!-- _______________________________________________________________________ -->
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<div class="doc_subsection"> <a name="informed">Stay Informed</a> </div>
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<div class="doc_text">
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<p>Developers should stay informed by reading at least the
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<a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">llvmdev</a>
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email list. If you are doing anything more than just casual work on LLVM,
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it is suggested that you also subscribe to the
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<a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits">llvm-commits</a>
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list and pay attention to changes being made by others.</p>
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<p>We recommend that active developers register an email account with
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<a href="http://llvm.org/bugs/">LLVM Bugzilla</a> and preferably subscribe to
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the <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmbugs">llvm-bugs</a>
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email list to keep track of bugs and enhancements occurring in LLVM.</p>
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</div>
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<!-- _______________________________________________________________________ -->
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<div class="doc_subsection"> <a name="patches">Making a Patch</a></div>
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<div class="doc_text">
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<p>When making a patch for review, the goal is to make it as easy for the
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reviewer to read it as possible. As such, we recommend that you:</p>
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<ol>
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<li>Make your patch against the CVS HEAD (main development trunk),
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not a branch, and not an old version of LLVM. This makes it easy to
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apply the patch.</li>
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<li>Similarly, patches should be submitted soon after they are generated.
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Old patches may not apply correctly if the underlying code changes between
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the time the patch was created and the time it is applied.</li>
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<li>Patches should be made with this command:
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<pre>cvs diff -Ntdup -5</pre>
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or with the utility <tt>utils/mkpatch</tt>, which makes it easy to read the
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diff.</li>
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<li>Patches should not include differences in generated code such as the
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code generated by <tt>flex</tt>, <tt>bison</tt> or <tt>tblgen</tt>. The
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<tt>utils/mkpatch</tt> utility takes care of this for you.</li>
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</ol>
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<p>When sending a patch to a mailing list, it is a good idea to send it as an
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<em>attachment</em> to the message, not embedded into the text of the
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message. This ensures that your mailer will not mangle the patch when it
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sends it (e.g. by making whitespace changes or by wrapping lines).</p>
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</div>
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<!-- _______________________________________________________________________ -->
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<div class="doc_subsection"> <a name="reviews">Code Reviews</a></div>
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<div class="doc_text">
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<p>LLVM has a code review policy. Code review is one way to increase the
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quality of software. We generally follow these policies:</p>
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<ol>
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<li>All developers are required to have significant changes reviewed
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before they are committed to the repository.</li>
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<li>Code reviews are conducted by email, usually on the llvm-commits
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list.</li>
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<li>Code can be reviewed either before it is committed or after. We expect
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major changes to be reviewed before being committed, but smaller
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changes (or changes where the developer owns the component) can be
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reviewed after commit.</li>
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<li>The developer responsible for a code change is also responsible for
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making all necessary review-related changes.</li>
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<li>Code review can be an iterative process, which continues until the patch
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is ready to be committed.</li>
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</ol>
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<p>Developers should participate in code reviews as both reviewers and
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reviewees. If someone is kind enough to review your code, you should
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return the favor for someone else. Note that anyone is welcome to review
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and give feedback on a patch, but only people with CVS write access can
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approve it.</p>
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</div>
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<!-- _______________________________________________________________________ -->
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<div class="doc_subsection"> <a name="testcases">Test Cases</a></div>
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<div class="doc_text">
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<p>Developers are required to create test cases for any bugs fixed and any new
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features added. Some tips for getting your testcase approved:</p>
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<ol>
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<li>All feature and regression test cases are added to the
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<tt>llvm/test</tt> directory. The appropriate sub-directory should be
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selected (see the <a href="TestingGuide.html">Testing Guide</a> for
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details).</li>
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<li>Test cases should be written in
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<a href="LangRef.html">LLVM assembly language</a> unless the
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feature or regression being tested requires another language (e.g. the
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bug being fixed or feature being implemented is in the llvm-gcc C++
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front-end, in which case it must be written in C++).</li>
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<li>Test cases, especially for regressions, should be reduced as much as
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possible, by <a href="CommandGuide/html/bugpoint.html">bugpoint</a> or
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manually. It is unacceptable
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to place an entire failing program into <tt>llvm/test</tt> as this creates
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a <i>time-to-test</i> burden on all developers. Please keep them short.</li>
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</ol>
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<p>Note that llvm/test is designed for regression and small feature tests
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only. More extensive test cases (e.g., entire applications, benchmarks,
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etc) should be added to the <tt>llvm-test</tt> test suite. The llvm-test
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suite is for coverage (correctness, performance, etc) testing, not feature
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or regression testing.</p>
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</div>
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2007-02-13 09:06:01 +00:00
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<!-- _______________________________________________________________________ -->
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<div class="doc_subsection"> <a name="quality">Quality</a></div>
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<div class="doc_text">
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<p>The minimum quality standards that any change must satisfy before being
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committed to the main development branch are:</p>
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<ol>
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<li>Code must adhere to the
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<a href="CodingStandards.html">LLVM Coding Standards</a>.</li>
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<li>Code must compile cleanly (no errors, no warnings) on at least one
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platform.</li>
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<li>Bug fixes and new features should <a href="#testcases">include a
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testcase</a> so we know if the fix/feature ever regresses in the
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future.</li>
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<li>Code must pass the dejagnu (<tt>llvm/test</tt>) test suite.</li>
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<li>The code must not cause regressions on a reasonable subset of llvm-test,
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where "reasonable" depends on the contributor's judgement and the scope
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of the change (more invasive changes require more testing). A reasonable
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subset is "<tt>llvm-test/MultiSource/Benchmarks</tt>".</li>
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</ol>
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<p>Additionally, the committer is responsible for addressing any problems
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found in the future that the change is responsible for. For example:</p>
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<ul>
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<li>The code should compile cleanly on all supported platforms.</li>
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<li>The changes should not cause any correctness regressions in the
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<tt>llvm-test</tt> suite and must not cause any major performance
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regressions.</li>
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<li>The change set should not cause performance or correctness regressions
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for the LLVM tools.</li>
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<li>The changes should not cause performance or correctness regressions in
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code compiled by LLVM on all applicable targets.</li>
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<li>You are expected to address any <a href="http://llvm.org/bugs/">bugzilla
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bugs</a> that result from your change.</li>
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</ul>
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2007-02-19 06:57:16 +00:00
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<p>We prefer for this to be handled before submission but understand that it
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isn't possible to test all of this for every submission. Our nightly
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testing
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infrastructure normally finds these problems. A good rule of thumb is to
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check the nightly testers for regressions the day after your change.</p>
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<p>Commits that violate these quality standards (e.g. are very broken) may
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be reverted. This is necessary when the change blocks other developers from
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making progress. The developer is welcome to re-commit the change after
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the problem has been fixed.</p>
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</div>
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<!-- _______________________________________________________________________ -->
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<div class="doc_subsection">
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<a name="commitaccess">Obtaining Commit Access</a></div>
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<div class="doc_text">
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<p>
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We grant commit access to contributors with a track record of submitting high
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quality patches. If you would like commit access, please send an email to the
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<a href="mailto:llvm-oversight@cs.uiuc.edu">LLVM oversight group</a>.</p>
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<p>If you have recently been granted commit access, these policies apply:</p>
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<ol>
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<li>You are granted <i>commit-after-approval</i> to all parts of LLVM.
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To get approval, submit a <a href="#patches">patch</a> to
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<a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits">
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llvm-commits</a>. When approved you may commit it yourself.</li>
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<li>You are allowed to commit patches without approval which you think are
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obvious. This is clearly a subjective decision — we simply expect you
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to use good judgement. Examples include: fixing build breakage, reverting
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obviously broken patches, documentation/comment changes, any other minor
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changes.</li>
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|
|
|
|
<li>You are allowed to commit patches without approval to those portions
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2007-02-19 06:57:16 +00:00
|
|
|
of LLVM that you have contributed or maintain (i.e., have been assigned
|
2007-02-19 03:50:31 +00:00
|
|
|
responsibility for), with the proviso that such commits must not break the
|
|
|
|
|
build. This is a "trust but verify" policy and commits of this nature are
|
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|
|
|
reviewed after they are committed.</li>
|
|
|
|
|
<li>Multiple violations of these policies or a single egregious violation
|
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|
|
|
may cause commit access to be revoked.</li>
|
|
|
|
|
</ol>
|
2007-02-19 06:57:16 +00:00
|
|
|
|
|
|
|
|
<p>In any case, your changes are still subject to <a href="#reviews">code
|
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|
|
|
review</a> (either before or after they are committed, depending on the nature
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|
|
|
of the change). You are encouraged to review other peoples' patches as well,
|
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|
|
|
but your aren't required to.</p>
|
2007-02-19 03:50:31 +00:00
|
|
|
|
|
|
|
|
</div>
|
|
|
|
|
|
|
|
|
|
<!-- _______________________________________________________________________ -->
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2007-02-19 05:43:04 +00:00
|
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<div class="doc_subsection"> <a name="newwork">Making a Major Change</a></div>
|
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<div class="doc_text">
|
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<p>When a developer begins a major new project with the aim of contributing
|
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it back to LLVM, s/he should inform the community with an email to
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2007-02-19 06:57:16 +00:00
|
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the <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">llvmdev</a>
|
2007-02-19 05:43:04 +00:00
|
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|
email list, to the extent possible. The reason for this is to:
|
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|
|
|
<ol>
|
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|
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|
<li>keep the community informed about future changes to LLVM, </li>
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2007-02-19 06:57:16 +00:00
|
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<li>avoid duplication of effort by preventing multiple parties working on
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|
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the same thing and not knowing about it, and</li>
|
2007-02-19 05:43:04 +00:00
|
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<li>ensure that any technical issues around the proposed work are
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discussed and resolved before any significant work is done.</li>
|
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|
|
|
</ol>
|
|
|
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<p>The design of LLVM is carefully controlled to ensure that all the pieces
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|
fit together well and are as consistent as possible. If you plan to make a
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2007-02-19 06:57:16 +00:00
|
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|
major change to the way LLVM works or want to add a major new extension, it
|
|
|
|
|
is a good idea to get consensus with the development
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2007-02-19 05:43:04 +00:00
|
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|
community before you start working on it.</p>
|
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2007-02-19 06:05:58 +00:00
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<p>Once the design of the new feature is finalized, the work itself should be
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done as a series of <a href="#incremental">incremental changes</a>, not as
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a long-term development branch.</p>
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|
2007-02-19 05:43:04 +00:00
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</div>
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|
|
|
|
|
|
<!-- _______________________________________________________________________ -->
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2007-02-19 06:05:58 +00:00
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<div class="doc_subsection"> <a name="incremental">Incremental Development</a>
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2007-02-19 03:50:31 +00:00
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</div>
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<div class="doc_text">
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2007-02-19 06:05:58 +00:00
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<p>In the LLVM project, we do all significant changes as a series of
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incremental patches. We have a strong dislike for huge changes or
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long-term development branches. Long-term development branches have a
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|
number of drawbacks:</p>
|
2007-02-19 03:50:31 +00:00
|
|
|
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|
<ol>
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|
<li>Branches must have mainline merged into them periodically. If the branch
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|
development and mainline development occur in the same pieces of code,
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|
resolving merge conflicts can take a lot of time.</li>
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|
<li>Other people in the community tend to ignore work on branches.</li>
|
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|
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|
<li>Huge changes (produced when a branch is merged back onto mainline) are
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|
|
|
extremely difficult to <a href="#reviews">code review</a>.</li>
|
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|
|
|
<li>Branches are not routinely tested by our nightly tester
|
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|
|
infrastructure.</li>
|
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|
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|
<li>Changes developed as monolithic large changes often don't work until the
|
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|
|
|
entire set of changes is done. Breaking it down into a set of smaller
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|
|
|
changes increases the odds that any of the work will be committed to the
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|
|
|
main repository.</li>
|
|
|
|
|
</ol>
|
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<p>
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To address these problems, LLVM uses an incremental development style and we
|
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require contributors to follow this practice when making a large/invasive
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change. Some tips:</p>
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|
|
|
|
|
|
<ul>
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|
<li>Large/invasive changes usually have a number of secondary changes that
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|
are required before the big change can be made (e.g. API cleanup, etc).
|
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|
These sorts of changes can often be done before the major change is done,
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|
|
|
independently of that work.</li>
|
|
|
|
|
<li>The remaining inter-related work should be decomposed into unrelated
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|
|
sets of changes if possible. Once this is done, define the first increment
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|
|
|
and get consensus on what the end goal of the change is.</li>
|
2007-02-19 05:59:30 +00:00
|
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|
|
|
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|
<li>Each change in the set can be stand alone (e.g. to fix a bug), or part
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|
|
of a planned series of changes that works towards the development goal.</li>
|
|
|
|
|
|
|
|
|
|
<li>Each change should be kept as small as possible. This simplifies your
|
2007-02-19 03:50:31 +00:00
|
|
|
work (into a logical progression), simplifies code review and reduces the
|
|
|
|
|
chance that you will get negative feedback on the change. Small increments
|
|
|
|
|
also facilitate the maintenance of a high quality code base.</li>
|
2007-02-19 05:59:30 +00:00
|
|
|
|
2007-02-19 03:50:31 +00:00
|
|
|
<li>Often, an independent precursor to a big change is to add a new API and
|
|
|
|
|
slowly migrate clients to use the new API. Each change to use the new
|
|
|
|
|
API is often "obvious" and can be committed without review. Once the
|
2007-02-19 06:57:16 +00:00
|
|
|
new API is in place and used, it is much easier to replace the
|
|
|
|
|
underlying implementation of the API. This implementation change is
|
|
|
|
|
logically separate from the API change.</li>
|
2007-02-19 03:50:31 +00:00
|
|
|
</ul>
|
|
|
|
|
|
|
|
|
|
<p>If you are interested in making a large change, and this scares you, please
|
|
|
|
|
make sure to first <a href="#newwork">discuss the change/gather
|
2007-02-19 06:57:16 +00:00
|
|
|
consensus</a> then ask about the best way to go about making
|
2007-02-19 03:50:31 +00:00
|
|
|
the change.</p>
|
|
|
|
|
</div>
|
|
|
|
|
|
|
|
|
|
<!-- _______________________________________________________________________ -->
|
2007-02-19 05:43:04 +00:00
|
|
|
<div class="doc_subsection"><a name="attribution">Attribution of
|
|
|
|
|
Changes</a></div>
|
2007-02-19 03:50:31 +00:00
|
|
|
<div class="doc_text">
|
|
|
|
|
<p>We believe in correct attribution of contributions to
|
|
|
|
|
their contributors. However, we do not want the source code to be littered
|
|
|
|
|
with random attributions (this is noisy/distracting and revision control
|
|
|
|
|
keeps a perfect history of this anyway). As such, we follow these rules:</p>
|
|
|
|
|
<ol>
|
|
|
|
|
<li>Developers who originate new files in LLVM should place their name at
|
|
|
|
|
the top of the file per the
|
|
|
|
|
<a href="CodingStandards.html#scf_commenting">Coding Standards</a>.</li>
|
|
|
|
|
<li>There should be only one name at the top of the file and it should be
|
|
|
|
|
the person who created the file.</li>
|
|
|
|
|
<li>Placing your name in the file does not imply <a
|
2007-02-19 06:19:16 +00:00
|
|
|
href="#clp">copyright</a>: it is only used to attribute the file to
|
2007-02-19 03:50:31 +00:00
|
|
|
its original author.</li>
|
|
|
|
|
<li>Developers should be aware that after some time has passed, the name at
|
|
|
|
|
the top of a file may become meaningless as maintenance/ownership of files
|
2007-02-19 06:57:16 +00:00
|
|
|
changes. Despite this, once set, the attribution of a file never changes.
|
|
|
|
|
Revision control keeps an accurate history of contributions.</li>
|
2007-02-19 03:50:31 +00:00
|
|
|
<li>Developers should maintain their entry in the
|
|
|
|
|
<a href="http://llvm.org/cvsweb/cvsweb.cgi/llvm/CREDITS.TXT?rev=HEAD&content-type=text/x-cvsweb-markup">CREDITS.txt</a>
|
|
|
|
|
file to summarize their contributions.</li>
|
|
|
|
|
<li>Commit comments should contain correct attribution of the person who
|
|
|
|
|
submitted the patch if that person is not the committer (i.e. when a
|
|
|
|
|
developer with commit privileges commits a patch for someone else).</li>
|
|
|
|
|
</ol>
|
|
|
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
2007-02-13 09:06:01 +00:00
|
|
|
|
2007-02-14 07:22:19 +00:00
|
|
|
<!--=========================================================================-->
|
2007-02-19 06:19:16 +00:00
|
|
|
<div class="doc_section">
|
|
|
|
|
<a name="clp">Copyright, License, and Patents</a>
|
|
|
|
|
</div>
|
2007-02-14 07:22:19 +00:00
|
|
|
<!--=========================================================================-->
|
2007-02-19 03:50:31 +00:00
|
|
|
|
2007-02-14 07:22:19 +00:00
|
|
|
<div class="doc_text">
|
2007-02-19 17:38:38 +00:00
|
|
|
<p>This section addresses the issues of copyright, license and patents for
|
|
|
|
|
the LLVM project.
|
2007-02-14 07:22:19 +00:00
|
|
|
Currently, the University of Illinois is the LLVM copyright holder and the
|
|
|
|
|
terms of its license to LLVM users and developers is the
|
|
|
|
|
<a href="http://www.opensource.org/licenses/UoI-NCSA.php">University of
|
2007-02-19 06:57:16 +00:00
|
|
|
Illinois/NCSA Open Source License</a>.</p>
|
2007-02-14 07:22:19 +00:00
|
|
|
|
|
|
|
|
<div class="doc_notes">
|
2007-02-19 03:50:31 +00:00
|
|
|
<p><b>NOTE: This section deals with legal matters but does not provide
|
2007-02-19 17:38:38 +00:00
|
|
|
legal advice. We are not lawyers, please seek legal counsel from an
|
2007-02-19 03:50:31 +00:00
|
|
|
attorney.</b></p>
|
2007-02-14 07:22:19 +00:00
|
|
|
</div>
|
|
|
|
|
</div>
|
|
|
|
|
|
|
|
|
|
<!-- _______________________________________________________________________ -->
|
|
|
|
|
<div class="doc_subsection"><a name="copyright">Copyright</a></div>
|
|
|
|
|
<div class="doc_text">
|
|
|
|
|
<p>
|
2007-02-14 16:21:10 +00:00
|
|
|
<p>For consistency and ease of management, the project requires the
|
2007-02-19 03:50:31 +00:00
|
|
|
copyright for all LLVM software to be held by a single copyright holder:
|
|
|
|
|
the University of Illinois (UIUC).</p>
|
|
|
|
|
|
|
|
|
|
<p>
|
|
|
|
|
Although UIUC may eventually reassign the copyright of the software to another
|
|
|
|
|
entity (e.g. a dedicated non-profit "LLVM Organization", or something)
|
|
|
|
|
the intent for the project is to always have a single entity hold the
|
|
|
|
|
copyrights to LLVM at any given time.</p>
|
|
|
|
|
|
|
|
|
|
<p>We believe that having a single copyright
|
2007-02-14 07:22:19 +00:00
|
|
|
holder is in the best interests of all developers and users as it greatly
|
|
|
|
|
reduces the managerial burden for any kind of administrative or technical
|
2007-02-19 03:50:31 +00:00
|
|
|
decisions about LLVM. The goal of the LLVM project is to always keep the code
|
|
|
|
|
open and <a href="#license">licensed under a very liberal license</a>.</p>
|
2007-02-14 07:22:19 +00:00
|
|
|
</div>
|
2007-02-19 03:50:31 +00:00
|
|
|
|
2007-02-14 07:22:19 +00:00
|
|
|
<!-- _______________________________________________________________________ -->
|
|
|
|
|
<div class="doc_subsection"><a name="license">License</a></div>
|
|
|
|
|
<div class="doc_text">
|
2007-02-19 03:50:31 +00:00
|
|
|
<p>We intend to keep LLVM perpetually open source
|
|
|
|
|
and to use a liberal open source license. The current license is the
|
2007-02-14 16:21:10 +00:00
|
|
|
<a href="http://www.opensource.org/licenses/UoI-NCSA.php">
|
|
|
|
|
University of Illinois/NCSA Open Source License</a>, which boils
|
2007-02-14 07:22:19 +00:00
|
|
|
down to this:</p>
|
|
|
|
|
<ul>
|
|
|
|
|
<li>You can freely distribute LLVM.</li>
|
|
|
|
|
<li>You must retain the copyright notice if you redistribute LLVM.</li>
|
|
|
|
|
<li>Binaries derived from LLVM must reproduce the copyright notice.</li>
|
|
|
|
|
<li>You can't use our names to promote your LLVM derived products.</li>
|
|
|
|
|
<li>There's no warranty on LLVM at all.</li>
|
|
|
|
|
</ul>
|
2007-02-19 03:50:31 +00:00
|
|
|
|
|
|
|
|
<p>We believe this fosters the widest adoption of LLVM because it <b>allows
|
|
|
|
|
commercial products to be derived from LLVM</b> with few restrictions and
|
2007-02-14 22:55:40 +00:00
|
|
|
without a requirement for making any derived works also open source (i.e.
|
2007-02-19 03:50:31 +00:00
|
|
|
LLVM's license is not a "copyleft" license like the GPL). We suggest that you
|
|
|
|
|
read the <a href="http://www.opensource.org/licenses/UoI-NCSA.php">License</a>
|
2007-02-14 22:58:39 +00:00
|
|
|
if further clarification is needed.</p>
|
2007-02-19 03:50:31 +00:00
|
|
|
|
|
|
|
|
<p>Note that the LLVM Project does distribute some code that includes GPL
|
|
|
|
|
software (notably, llvm-gcc which is based on the GCC GPL source base).
|
|
|
|
|
This means that anything "linked" into to llvm-gcc must itself be compatible
|
|
|
|
|
with the GPL, and must be releasable under the terms of the GPL. This implies
|
2007-02-19 17:38:38 +00:00
|
|
|
that <b>any code linked into llvm-gcc and distributed to others may be
|
2007-02-19 06:57:16 +00:00
|
|
|
subject to
|
2007-02-19 03:50:31 +00:00
|
|
|
the viral aspects of the GPL</b>. This is not a problem for the main LLVM
|
|
|
|
|
distribution (which is already licensed under a more liberal license), but may
|
2007-02-19 06:57:16 +00:00
|
|
|
be a problem if you intend to base commercial development on llvm-gcc without
|
|
|
|
|
redistributing your source code.</p>
|
2007-02-19 03:50:31 +00:00
|
|
|
|
|
|
|
|
<p>We have no plans to change the license of LLVM. If you have questions
|
|
|
|
|
or comments about the license, please contact the <a
|
|
|
|
|
href="mailto:llvm-oversight@cs.uiuc.edu">LLVM Oversight Group</a>.</p>
|
|
|
|
|
|
2007-02-14 07:22:19 +00:00
|
|
|
</div>
|
2007-02-19 06:05:58 +00:00
|
|
|
|
|
|
|
|
<!-- _______________________________________________________________________ -->
|
|
|
|
|
<div class="doc_subsection"><a name="patents">Patents</a></div>
|
|
|
|
|
<div class="doc_text">
|
|
|
|
|
|
2007-02-19 06:13:50 +00:00
|
|
|
<p>To the best of our knowledge, LLVM does not infringe on any patents (we have
|
|
|
|
|
actually removed code from LLVM in the past that was found to infringe).
|
2007-02-19 06:15:33 +00:00
|
|
|
Having code in LLVM that infringes on patents would violate an important
|
|
|
|
|
goal of the project by making it hard or impossible to reuse the code for
|
|
|
|
|
arbitrary purposes (including commercial use).</p>
|
2007-02-19 06:13:50 +00:00
|
|
|
|
|
|
|
|
<p>When contributing code, we expect contributors to notify us of any potential
|
|
|
|
|
for patent-related trouble with their changes. If you own the rights to a
|
|
|
|
|
patent and would like to contribute code to LLVM that relies on it, we
|
|
|
|
|
require that you sign an agreement that allows any other user of LLVM to
|
|
|
|
|
freely use your patent. Please contact the <a
|
|
|
|
|
href="mailto:llvm-oversight@cs.uiuc.edu">oversight group</a> for more
|
|
|
|
|
details.</p>
|
2007-02-19 06:05:58 +00:00
|
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
2007-02-14 07:22:19 +00:00
|
|
|
<!-- _______________________________________________________________________ -->
|
|
|
|
|
<div class="doc_subsection"><a name="devagree">Developer Agreements</a></div>
|
|
|
|
|
<div class="doc_text">
|
2007-02-19 03:50:31 +00:00
|
|
|
<p>With regards to the LLVM copyright and licensing, developers agree to
|
|
|
|
|
assign their copyrights to UIUC for any contribution made so that
|
|
|
|
|
the entire software base can be managed by a single copyright holder. This
|
|
|
|
|
implies that any contributions can be licensed under the license that the
|
2007-02-19 05:49:11 +00:00
|
|
|
project uses.</p>
|
2007-02-14 07:22:19 +00:00
|
|
|
</div>
|
|
|
|
|
|
2007-02-13 09:06:01 +00:00
|
|
|
<!-- *********************************************************************** -->
|
|
|
|
|
<hr>
|
|
|
|
|
<address>
|
|
|
|
|
<a href="http://jigsaw.w3.org/css-validator/check/referer"><img
|
|
|
|
|
src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
|
|
|
|
|
<a href="http://validator.w3.org/check/referer"><img
|
|
|
|
|
src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
|
2007-02-19 06:15:33 +00:00
|
|
|
Written by the
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2007-02-14 07:57:48 +00:00
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<a href="mailto:llvm-oversight@cs.uiuc.edu">LLVM Oversight Group</a><br>
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2007-02-13 09:06:01 +00:00
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<a href="http://llvm.org">The LLVM Compiler Infrastructure</a><br>
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Last modified: $Date$
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