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| |
| <div class="doc_title">LLVM Developer Policy</div> |
| <ol> |
| <li><a href="#introduction">Introduction</a></li> |
| <li><a href="#policies">Developer Policies</a> |
| <ol> |
| <li><a href="#informed">Stay Informed</a></li> |
| <li><a href="#patches">Making a Patch</a></li> |
| <li><a href="#reviews">Code Reviews</a></li> |
| <li><a href="#owners">Code Owners</a></li> |
| <li><a href="#testcases">Test Cases</a></li> |
| <li><a href="#quality">Quality</a></li> |
| <li><a href="#commitaccess">Obtaining Commit Access</a></li> |
| <li><a href="#newwork">Making a Major Change</a></li> |
| <li><a href="#incremental">Incremental Development</a></li> |
| <li><a href="#attribution">Attribution of Changes</a></li> |
| </ol></li> |
| <li><a href="#clp">Copyright, License, and Patents</a> |
| <ol> |
| <li><a href="#copyright">Copyright</a></li> |
| <li><a href="#license">License</a></li> |
| <li><a href="#patents">Patents</a></li> |
| <li><a href="#devagree">Developer Agreements</a></li> |
| </ol></li> |
| </ol> |
| <div class="doc_author">Written by the LLVM Oversight Team</div> |
| |
| <!--=========================================================================--> |
| <div class="doc_section"><a name="introduction">Introduction</a></div> |
| <!--=========================================================================--> |
| <div class="doc_text"> |
| <p>This document contains the LLVM Developer Policy which defines the project's |
| policy towards developers and their contributions. The intent of this policy |
| is to eliminate miscommunication, rework, and confusion that might arise from |
| the distributed nature of LLVM's development. By stating the policy in clear |
| terms, we hope each developer can know ahead of time what to expect when |
| making LLVM contributions.</p> |
| <p>This policy is also designed to accomplish the following objectives:</p> |
| |
| <ol> |
| <li>Attract both users and developers to the LLVM project.</li> |
| |
| <li>Make life as simple and easy for contributors as possible.</li> |
| |
| <li>Keep the top of Subversion trees as stable as possible.</li> |
| </ol> |
| |
| <p>This policy is aimed at frequent contributors to LLVM. People interested in |
| contributing one-off patches can do so in an informal way by sending them to |
| the |
| <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits">llvm-commits |
| mailing list</a> and engaging another developer to see it through the |
| process.</p> |
| </div> |
| |
| <!--=========================================================================--> |
| <div class="doc_section"><a name="policies">Developer Policies</a></div> |
| <!--=========================================================================--> |
| <div class="doc_text"> |
| <p>This section contains policies that pertain to frequent LLVM developers. We |
| always welcome <a href="#patches">one-off patches</a> from people who do not |
| routinely contribute to LLVM, but we expect more from frequent contributors |
| to keep the system as efficient as possible for everyone. Frequent LLVM |
| contributors are expected to meet the following requirements in order for |
| LLVM to maintain a high standard of quality.<p> |
| </div> |
| |
| <!-- _______________________________________________________________________ --> |
| <div class="doc_subsection"> <a name="informed">Stay Informed</a> </div> |
| <div class="doc_text"> |
| <p>Developers should stay informed by reading at least the |
| <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">llvmdev</a> email |
| list. If you are doing anything more than just casual work on LLVM, it is |
| suggested that you also subscribe to the |
| <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits">llvm-commits</a> |
| list and pay attention to changes being made by others.</p> |
| |
| <p>We recommend that active developers register an email account with |
| <a href="http://llvm.org/bugs/">LLVM Bugzilla</a> and preferably subscribe to |
| the <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmbugs">llvm-bugs</a> |
| email list to keep track of bugs and enhancements occurring in LLVM.</p> |
| </div> |
| |
| <!-- _______________________________________________________________________ --> |
| <div class="doc_subsection"> <a name="patches">Making a Patch</a></div> |
| |
| <div class="doc_text"> |
| <p>When making a patch for review, the goal is to make it as easy for the |
| reviewer to read it as possible. As such, we recommend that you:</p> |
| |
| <ol> |
| <li>Make your patch against the Subversion trunk, not a branch, and not an old |
| version of LLVM. This makes it easy to apply the patch. For information |
| on how to check out SVN trunk, please see the <a |
| href="GettingStarted.html#checkout">Getting Started Guide</a>.</li> |
| |
| <li>Similarly, patches should be submitted soon after they are generated. Old |
| patches may not apply correctly if the underlying code changes between the |
| time the patch was created and the time it is applied.</li> |
| |
| <li>Patches should be made with this command: |
| <div class="doc_code"> |
| <pre> |
| svn diff |
| </pre> |
| </div> |
| or with the utility <tt>utils/mkpatch</tt>, which makes it easy to read |
| the diff.</li> |
| |
| <li>Patches should not include differences in generated code such as the code |
| generated by <tt>autoconf</tt> or <tt>tblgen</tt>. The |
| <tt>utils/mkpatch</tt> utility takes care of this for you.</li> |
| </ol> |
| |
| <p>When sending a patch to a mailing list, it is a good idea to send it as an |
| <em>attachment</em> to the message, not embedded into the text of the |
| message. This ensures that your mailer will not mangle the patch when it |
| sends it (e.g. by making whitespace changes or by wrapping lines).</p> |
| |
| <p><em>For Thunderbird users:</em> Before submitting a patch, please open |
| <em>Preferences → Advanced → General → Config Editor</em>, |
| find the key <tt>mail.content_disposition_type</tt>, and set its value to |
| <tt>1</tt>. Without this setting, Thunderbird sends your attachment using |
| <tt>Content-Disposition: inline</tt> rather than <tt>Content-Disposition: |
| attachment</tt>. Apple Mail gamely displays such a file inline, making it |
| difficult to work with for reviewers using that program.</p> |
| </div> |
| |
| <!-- _______________________________________________________________________ --> |
| <div class="doc_subsection"> <a name="reviews">Code Reviews</a></div> |
| <div class="doc_text"> |
| <p>LLVM has a code review policy. Code review is one way to increase the quality |
| of software. We generally follow these policies:</p> |
| |
| <ol> |
| <li>All developers are required to have significant changes reviewed before |
| they are committed to the repository.</li> |
| |
| <li>Code reviews are conducted by email, usually on the llvm-commits |
| list.</li> |
| |
| <li>Code can be reviewed either before it is committed or after. We expect |
| major changes to be reviewed before being committed, but smaller changes |
| (or changes where the developer owns the component) can be reviewed after |
| commit.</li> |
| |
| <li>The developer responsible for a code change is also responsible for making |
| all necessary review-related changes.</li> |
| |
| <li>Code review can be an iterative process, which continues until the patch |
| is ready to be committed.</li> |
| </ol> |
| |
| <p>Developers should participate in code reviews as both reviewers and |
| reviewees. If someone is kind enough to review your code, you should return |
| the favor for someone else. Note that anyone is welcome to review and give |
| feedback on a patch, but only people with Subversion write access can approve |
| it.</p> |
| </div> |
| |
| <!-- _______________________________________________________________________ --> |
| <div class="doc_subsection"> <a name="owners">Code Owners</a></div> |
| <div class="doc_text"> |
| |
| <p>The LLVM Project relies on two features of its process to maintain rapid |
| development in addition to the high quality of its source base: the |
| combination of code review plus post-commit review for trusted maintainers. |
| Having both is a great way for the project to take advantage of the fact that |
| most people do the right thing most of the time, and only commit patches |
| without pre-commit review when they are confident they are right.</p> |
| |
| <p>The trick to this is that the project has to guarantee that all patches that |
| are committed are reviewed after they go in: you don't want everyone to |
| assume someone else will review it, allowing the patch to go unreviewed. To |
| solve this problem, we have a notion of an 'owner' for a piece of the code. |
| The sole responsibility of a code owner is to ensure that a commit to their |
| area of the code is appropriately reviewed, either by themself or by someone |
| else. The current code owners are:</p> |
| |
| <ol> |
| <li><b>Evan Cheng</b>: Code generator and all targets.</li> |
| |
| <li><b>Doug Gregor</b>: Clang Basic, Lex, Parse, and Sema Libraries.</li> |
| |
| <li><b>Anton Korobeynikov</b>: Exception handling, debug information, and |
| Windows codegen.</li> |
| |
| <li><b>Ted Kremenek</b>: Clang Static Analyzer.</li> |
| |
| <li><b>Chris Lattner</b>: Everything not covered by someone else.</li> |
| |
| <li><b>Duncan Sands</b>: llvm-gcc 4.2.</li> |
| </ol> |
| |
| <p>Note that code ownership is completely different than reviewers: anyone can |
| review a piece of code, and we welcome code review from anyone who is |
| interested. Code owners are the "last line of defense" to guarantee that all |
| patches that are committed are actually reviewed.</p> |
| |
| <p>Being a code owner is a somewhat unglamorous position, but it is incredibly |
| important for the ongoing success of the project. Because people get busy, |
| interests change, and unexpected things happen, code ownership is purely |
| opt-in, and anyone can choose to resign their "title" at any time. For now, |
| we do not have an official policy on how one gets elected to be a code |
| owner.</p> |
| </div> |
| |
| <!-- _______________________________________________________________________ --> |
| <div class="doc_subsection"> <a name="testcases">Test Cases</a></div> |
| <div class="doc_text"> |
| <p>Developers are required to create test cases for any bugs fixed and any new |
| features added. Some tips for getting your testcase approved:</p> |
| |
| <ol> |
| <li>All feature and regression test cases are added to the |
| <tt>llvm/test</tt> directory. The appropriate sub-directory should be |
| selected (see the <a href="TestingGuide.html">Testing Guide</a> for |
| details).</li> |
| |
| <li>Test cases should be written in <a href="LangRef.html">LLVM assembly |
| language</a> unless the feature or regression being tested requires |
| another language (e.g. the bug being fixed or feature being implemented is |
| in the llvm-gcc C++ front-end, in which case it must be written in |
| C++).</li> |
| |
| <li>Test cases, especially for regressions, should be reduced as much as |
| possible, by <a href="Bugpoint.html">bugpoint</a> or manually. It is |
| unacceptable to place an entire failing program into <tt>llvm/test</tt> as |
| this creates a <i>time-to-test</i> burden on all developers. Please keep |
| them short.</li> |
| </ol> |
| |
| <p>Note that llvm/test is designed for regression and small feature tests |
| only. More extensive test cases (e.g., entire applications, benchmarks, etc) |
| should be added to the <tt>llvm-test</tt> test suite. The llvm-test suite is |
| for coverage (correctness, performance, etc) testing, not feature or |
| regression testing.</p> |
| </div> |
| |
| <!-- _______________________________________________________________________ --> |
| <div class="doc_subsection"> <a name="quality">Quality</a></div> |
| <div class="doc_text"> |
| <p>The minimum quality standards that any change must satisfy before being |
| committed to the main development branch are:</p> |
| |
| <ol> |
| <li>Code must adhere to the <a href="CodingStandards.html">LLVM Coding |
| Standards</a>.</li> |
| |
| <li>Code must compile cleanly (no errors, no warnings) on at least one |
| platform.</li> |
| |
| <li>Bug fixes and new features should <a href="#testcases">include a |
| testcase</a> so we know if the fix/feature ever regresses in the |
| future.</li> |
| |
| <li>Code must pass the dejagnu (<tt>llvm/test</tt>) test suite.</li> |
| |
| <li>The code must not cause regressions on a reasonable subset of llvm-test, |
| where "reasonable" depends on the contributor's judgement and the scope of |
| the change (more invasive changes require more testing). A reasonable |
| subset might be something like |
| "<tt>llvm-test/MultiSource/Benchmarks</tt>".</li> |
| </ol> |
| |
| <p>Additionally, the committer is responsible for addressing any problems found |
| in the future that the change is responsible for. For example:</p> |
| |
| <ul> |
| <li>The code should compile cleanly on all supported platforms.</li> |
| |
| <li>The changes should not cause any correctness regressions in the |
| <tt>llvm-test</tt> suite and must not cause any major performance |
| regressions.</li> |
| |
| <li>The change set should not cause performance or correctness regressions for |
| the LLVM tools.</li> |
| |
| <li>The changes should not cause performance or correctness regressions in |
| code compiled by LLVM on all applicable targets.</li> |
| |
| <li>You are expected to address any <a href="http://llvm.org/bugs/">bugzilla |
| bugs</a> that result from your change.</li> |
| </ul> |
| |
| <p>We prefer for this to be handled before submission but understand that it |
| isn't possible to test all of this for every submission. Our build bots and |
| nightly testing infrastructure normally finds these problems. A good rule of |
| thumb is to check the nightly testers for regressions the day after your |
| change. Build bots will directly email you if a group of commits that |
| included yours caused a failure. You are expected to check the build bot |
| messages to see if they are your fault and, if so, fix the breakage.</p> |
| |
| <p>Commits that violate these quality standards (e.g. are very broken) may be |
| reverted. This is necessary when the change blocks other developers from |
| making progress. The developer is welcome to re-commit the change after the |
| problem has been fixed.</p> |
| </div> |
| |
| <!-- _______________________________________________________________________ --> |
| <div class="doc_subsection"> |
| <a name="commitaccess">Obtaining Commit Access</a></div> |
| <div class="doc_text"> |
| |
| <p>We grant commit access to contributors with a track record of submitting high |
| quality patches. If you would like commit access, please send an email to |
| <a href="mailto:sabre@nondot.org">Chris</a> with the following |
| information:</p> |
| |
| <ol> |
| <li>The user name you want to commit with, e.g. "hacker".</li> |
| |
| <li>The full name and email address you want message to llvm-commits to come |
| from, e.g. "J. Random Hacker <hacker@yoyodyne.com>".</li> |
| |
| <li>A "password hash" of the password you want to use, e.g. "2ACR96qjUqsyM". |
| Note that you don't ever tell us what your password is, you just give it |
| to us in an encrypted form. To get this, run "htpasswd" (a utility that |
| comes with apache) in crypt mode (often enabled with "-d"), or find a web |
| page that will do it for you.</li> |
| </ol> |
| |
| <p>Once you've been granted commit access, you should be able to check out an |
| LLVM tree with an SVN URL of "https://username@llvm.org/..." instead of the |
| normal anonymous URL of "http://llvm.org/...". The first time you commit |
| you'll have to type in your password. Note that you may get a warning from |
| SVN about an untrusted key, you can ignore this. To verify that your commit |
| access works, please do a test commit (e.g. change a comment or add a blank |
| line). Your first commit to a repository may require the autogenerated email |
| to be approved by a mailing list. This is normal, and will be done when |
| the mailing list owner has time.</p> |
| |
| <p>If you have recently been granted commit access, these policies apply:</p> |
| |
| <ol> |
| <li>You are granted <i>commit-after-approval</i> to all parts of LLVM. To get |
| approval, submit a <a href="#patches">patch</a> to |
| <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits">llvm-commits</a>. |
| When approved you may commit it yourself.</li> |
| |
| <li>You are allowed to commit patches without approval which you think are |
| obvious. This is clearly a subjective decision — we simply expect |
| you to use good judgement. Examples include: fixing build breakage, |
| reverting obviously broken patches, documentation/comment changes, any |
| other minor changes.</li> |
| |
| <li>You are allowed to commit patches without approval to those portions of |
| LLVM that you have contributed or maintain (i.e., have been assigned |
| 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 |
| reviewed after they are committed.</li> |
| |
| <li>Multiple violations of these policies or a single egregious violation may |
| cause commit access to be revoked.</li> |
| </ol> |
| |
| <p>In any case, your changes are still subject to <a href="#reviews">code |
| review</a> (either before or after they are committed, depending on the |
| nature of the change). You are encouraged to review other peoples' patches |
| as well, but you aren't required to.</p> |
| </div> |
| |
| <!-- _______________________________________________________________________ --> |
| <div class="doc_subsection"> <a name="newwork">Making a Major Change</a></div> |
| <div class="doc_text"> |
| <p>When a developer begins a major new project with the aim of contributing it |
| back to LLVM, s/he should inform the community with an email to |
| the <a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">llvmdev</a> |
| email list, to the extent possible. The reason for this is to: |
| |
| <ol> |
| <li>keep the community informed about future changes to LLVM, </li> |
| |
| <li>avoid duplication of effort by preventing multiple parties working on the |
| same thing and not knowing about it, and</li> |
| |
| <li>ensure that any technical issues around the proposed work are discussed |
| and resolved before any significant work is done.</li> |
| </ol> |
| |
| <p>The design of LLVM is carefully controlled to ensure that all the pieces fit |
| together well and are as consistent as possible. If you plan to make a 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 community before you start |
| working on it.</p> |
| |
| <p>Once the design of the new feature is finalized, the work itself should be |
| done as a series of <a href="#incremental">incremental changes</a>, not as a |
| long-term development branch.</p> |
| </div> |
| |
| <!-- _______________________________________________________________________ --> |
| <div class="doc_subsection"> <a name="incremental">Incremental Development</a> |
| </div> |
| <div class="doc_text"> |
| <p>In the LLVM project, we do all significant changes as a series of incremental |
| patches. We have a strong dislike for huge changes or long-term development |
| branches. Long-term development branches have a number of drawbacks:</p> |
| |
| <ol> |
| <li>Branches must have mainline merged into them periodically. If the branch |
| development and mainline development occur in the same pieces of code, |
| resolving merge conflicts can take a lot of time.</li> |
| |
| <li>Other people in the community tend to ignore work on branches.</li> |
| |
| <li>Huge changes (produced when a branch is merged back onto mainline) are |
| extremely difficult to <a href="#reviews">code review</a>.</li> |
| |
| <li>Branches are not routinely tested by our nightly tester |
| infrastructure.</li> |
| |
| <li>Changes developed as monolithic large changes often don't work until the |
| entire set of changes is done. Breaking it down into a set of smaller |
| changes increases the odds that any of the work will be committed to the |
| main repository.</li> |
| </ol> |
| |
| <p>To address these problems, LLVM uses an incremental development style and we |
| require contributors to follow this practice when making a large/invasive |
| change. Some tips:</p> |
| |
| <ul> |
| <li>Large/invasive changes usually have a number of secondary changes that are |
| required before the big change can be made (e.g. API cleanup, etc). These |
| sorts of changes can often be done before the major change is done, |
| independently of that work.</li> |
| |
| <li>The remaining inter-related work should be decomposed into unrelated sets |
| of changes if possible. Once this is done, define the first increment and |
| get consensus on what the end goal of the change is.</li> |
| |
| <li>Each change in the set can be stand alone (e.g. to fix a bug), or part 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 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> |
| |
| <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 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> |
| </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 consensus</a> |
| then ask about the best way to go about making the change.</p> |
| </div> |
| |
| <!-- _______________________________________________________________________ --> |
| <div class="doc_subsection"><a name="attribution">Attribution of |
| Changes</a></div> |
| <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 code written by J. Random Hacker" (this is noisy and |
| distracting). In practice, the revision control system keeps a perfect |
| history of who changed what, and the CREDITS.txt file describes higher-level |
| contributions. If you commit a patch for someone else, please say "patch |
| contributed by J. Random Hacker!" in the commit message.</p> |
| |
| <p>Overall, please do not add contributor names to the source code.</p> |
| </div> |
| |
| <!--=========================================================================--> |
| <div class="doc_section"> |
| <a name="clp">Copyright, License, and Patents</a> |
| </div> |
| <!--=========================================================================--> |
| |
| <div class="doc_text"> |
| <p>This section addresses the issues of copyright, license and patents for the |
| LLVM project. 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 |
| Illinois/NCSA Open Source License</a>.</p> |
| |
| <div class="doc_notes"> |
| <p style="text-align:center;font-weight:bold">NOTE: This section deals with |
| legal matters but does not provide legal advice. We are not lawyers, please |
| seek legal counsel from an attorney.</p> |
| </div> |
| </div> |
| |
| <!-- _______________________________________________________________________ --> |
| <div class="doc_subsection"><a name="copyright">Copyright</a></div> |
| <div class="doc_text"> |
| <p>For consistency and ease of management, the project requires the 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") 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 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 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> |
| </div> |
| |
| <!-- _______________________________________________________________________ --> |
| <div class="doc_subsection"><a name="license">License</a></div> |
| <div class="doc_text"> |
| <p>We intend to keep LLVM perpetually open source and to use a liberal open |
| source license. The current license is the |
| <a href="http://www.opensource.org/licenses/UoI-NCSA.php">University of |
| Illinois/NCSA Open Source License</a>, which boils 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 (e.g. in |
| an included readme file).</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> |
| |
| <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 |
| without a requirement for making any derived works also open source (i.e. |
| 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> |
| if further clarification is needed.</p> |
| |
| <p>Note that the LLVM Project does distribute llvm-gcc, <b>which is GPL.</b> |
| This means that anything "linked" into llvm-gcc must itself be compatible |
| with the GPL, and must be releasable under the terms of the GPL. This |
| implies that <b>any code linked into llvm-gcc and distributed to others may |
| be subject to the viral aspects of the GPL</b> (for example, a proprietary |
| code generator linked into llvm-gcc must be made available under the GPL). |
| This is not a problem for code already distributed under a more liberal |
| license (like the UIUC license), and does not affect code generated by |
| llvm-gcc. It may be a problem if you intend to base commercial development |
| on llvm-gcc without redistributing your source code.</p> |
| |
| <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> |
| </div> |
| |
| <!-- _______________________________________________________________________ --> |
| <div class="doc_subsection"><a name="patents">Patents</a></div> |
| <div class="doc_text"> |
| <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). |
| 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> |
| |
| <p>When contributing code, we expect contributors to notify us of any potential |
| for patent-related trouble with their changes. If you or your employer own |
| the rights to a patent and would like to contribute code to LLVM that relies |
| on it, we require that the copyright owner 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> |
| </div> |
| |
| <!-- _______________________________________________________________________ --> |
| <div class="doc_subsection"><a name="devagree">Developer Agreements</a></div> |
| <div class="doc_text"> |
| <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 project |
| uses.</p> |
| |
| <p>When contributing code, you also affirm that you are legally entitled to |
| grant this copyright, personally or on behalf of your employer. If the code |
| belongs to some other entity, please raise this issue with the oversight |
| group before the code is committed.</p> |
| </div> |
| |
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