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<h1>LLVM Developer Policy</h1> | |
<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> | |
</ol></li> | |
</ol> | |
<div class="doc_author">Written by the LLVM Oversight Team</div> | |
<!--=========================================================================--> | |
<h2><a name="introduction">Introduction</a></h2> | |
<!--=========================================================================--> | |
<div> | |
<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. This policy covers all llvm.org subprojects, | |
including Clang, LLDB, etc.</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> | |
<!--=========================================================================--> | |
<h2><a name="policies">Developer Policies</a></h2> | |
<!--=========================================================================--> | |
<div> | |
<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> | |
<!-- _______________________________________________________________________ --> | |
<h3><a name="informed">Stay Informed</a></h3> | |
<div> | |
<p>Developers should stay informed by reading at least the "dev" mailing list | |
for the projects you are interested in, such as | |
<a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">llvmdev</a> for | |
LLVM, <a href="http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev">cfe-dev</a> | |
for Clang, or <a | |
href="http://lists.cs.uiuc.edu/mailman/listinfo/lldb-dev">lldb-dev</a> | |
for LLDB. If you are doing anything more than just casual work on LLVM, it | |
is suggested that you also subscribe to the "commits" mailing list for the | |
subproject you're interested in, such as | |
<a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits">llvm-commits</a>, | |
<a href="http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits">cfe-commits</a>, | |
or <a href="http://lists.cs.uiuc.edu/mailman/listinfo/lldb-commits">lldb-commits</a>. | |
Reading the "commits" list and paying attention to changes being made by | |
others is a good way to see what other people are interested in and watching | |
the flow of the project as a whole.</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. We | |
really appreciate people who are proactive at catching incoming bugs in their | |
components and dealing with them promptly.</p> | |
</div> | |
<!-- _______________________________________________________________________ --> | |
<h3><a name="patches">Making a Patch</a></h3> | |
<div> | |
<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 <tt>svn diff</tt>, or similar. If you use | |
a different tool, make sure it uses the <tt>diff -u</tt> format and | |
that it doesn't contain clutter which makes it hard to read.</li> | |
<li>If you are modifying generated files, such as the top-level | |
<tt>configure</tt> script, please separate out those changes into | |
a separate patch from the rest of your changes.</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> | |
<!-- _______________________________________________________________________ --> | |
<h3><a name="reviews">Code Reviews</a></h3> | |
<div> | |
<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> | |
<!-- _______________________________________________________________________ --> | |
<h3><a name="owners">Code Owners</a></h3> | |
<div> | |
<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>Greg Clayton</b>: LLDB.</li> | |
<li><b>Doug Gregor</b>: Clang Frontend Libraries.</li> | |
<li><b>Howard Hinnant</b>: libc++.</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>John McCall</b>: Clang LLVM IR generation.</li> | |
<li><b>Jakob Olesen</b>: Register allocators and TableGen.</li> | |
<li><b>Duncan Sands</b>: dragonegg and 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> | |
<!-- _______________________________________________________________________ --> | |
<h3><a name="testcases">Test Cases</a></h3> | |
<div> | |
<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 and clang/test are 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> | |
<!-- _______________________________________________________________________ --> | |
<h3><a name="quality">Quality</a></h3> | |
<div> | |
<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 <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> | |
<!-- _______________________________________________________________________ --> | |
<h3><a name="commitaccess">Obtaining Commit Access</a></h3> | |
<div> | |
<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> | |
<!-- _______________________________________________________________________ --> | |
<h3><a name="newwork">Making a Major Change</a></h3> | |
<div> | |
<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> | |
<!-- _______________________________________________________________________ --> | |
<h3><a name="incremental">Incremental Development</a></h3> | |
<div> | |
<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> | |
<!-- _______________________________________________________________________ --> | |
<h3><a name="attribution">Attribution of Changes</a></h3> | |
<div> | |
<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> | |
<!--=========================================================================--> | |
<h2> | |
<a name="clp">Copyright, License, and Patents</a> | |
</h2> | |
<!--=========================================================================--> | |
<div> | |
<p>This section addresses the issues of copyright, license and patents for the | |
LLVM project. The copyright holder for the code is held by the individual | |
contributors of the code 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> | |
<!-- _______________________________________________________________________ --> | |
<h3><a name="copyright">Copyright</a></h3> | |
<div> | |
<p>The LLVM project does not require copyright assignments, which means that the | |
copyright for the code in the project is held by its respective contributors | |
who have each agreed to release their contributed code under the terms of the | |
<a href="#license">LLVM License</a>.</p> | |
<p>An implication of this is that the LLVM license is unlikely to ever change: | |
changing it would require tracking down all the contributors to LLVM and | |
getting them to agree that a license change is acceptable for their | |
contribution. Since there are no plans to change the license, this is not a | |
cause for concern.</p> | |
<p>As a contributor to the project, this means that you (or your company) retain | |
ownership of the code you contribute, that it cannot be used in a way that | |
contradicts the license (which is a liberal BSD-style license), and that the | |
license for your contributions won't change without your approval in the | |
future.</p> | |
</div> | |
<!-- _______________________________________________________________________ --> | |
<h3><a name="license">License</a></h3> | |
<div> | |
<p>We intend to keep LLVM perpetually open source and to use a liberal open | |
source license. All of the code in LLVM is available under 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>In addition to the UIUC license, the runtime library components of LLVM | |
(<b>compiler_rt and libc++</b>) are also licensed under the <a | |
href="http://www.opensource.org/licenses/mit-license.php">MIT license</a>, | |
which does not contain the binary redistribution clause. As a user of these | |
runtime libraries, it means that you can choose to use the code under either | |
license (and thus don't need the binary redistribution clause), and as a | |
contributor to the code that you agree that any contributions to these | |
libraries be licensed under both licenses. We feel that this is important | |
for runtime libraries, because they are implicitly linked into applications | |
and therefore should not subject those applications to the binary | |
redistribution clause. This also means that it is ok to move code from (e.g.) | |
libc++ to the LLVM core without concern, but that code cannot be moved from | |
the LLVM core to libc++ without the copyright owner's permission. | |
</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:llvmdev@cs.uiuc.edu">LLVM Developer's Mailing List</a>.</p> | |
</div> | |
<!-- _______________________________________________________________________ --> | |
<h3><a name="patents">Patents</a></h3> | |
<div> | |
<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> | |
<!-- *********************************************************************** --> | |
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<address> | |
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Written by the | |
<a href="mailto:llvm-oversight@cs.uiuc.edu">LLVM Oversight Group</a><br> | |
<a href="http://llvm.org/">The LLVM Compiler Infrastructure</a><br> | |
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