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                         <h1 id="getting-started"><a class="header" href="#getting-started">Getting Started</a></h1>
 <p>Thank you for your interest in contributing to Rust! There are many ways to
 contribute, and we appreciate all of them.</p>
 <ul>
 <li><a href="#asking-questions">Asking Questions</a>
 <ul>
 <li><a href="#experts">Experts</a></li>
 <li><a href="#etiquette">Etiquette</a></li>
 </ul>
 </li>
 <li><a href="#what-should-i-work-on">What should I work on?</a>
 <ul>
 <li><a href="#easy-or-mentored-issues">Easy or mentored issues</a></li>
 <li><a href="#recurring-work">Recurring work</a></li>
 <li><a href="#clippy-issues">Clippy issues</a></li>
 <li><a href="#diagnostic-issues">Diagnostic issues</a></li>
 <li><a href="#picking-up-abandoned-pull-requests">Picking up abandoned pull requests</a></li>
 <li><a href="#writing-tests">Writing tests</a></li>
 <li><a href="#contributing-to-std-standard-library">Contributing to std (standard library)</a></li>
 <li><a href="#contributing-code-to-other-rust-projects">Contributing code to other Rust projects</a></li>
 <li><a href="#other-ways-to-contribute">Other ways to contribute</a></li>
 </ul>
 </li>
 <li><a href="#cloning-and-building">Cloning and Building</a></li>
 <li><a href="#contributor-procedures">Contributor Procedures</a></li>
 <li><a href="#other-resources">Other Resources</a></li>
 </ul>
 <p>If this is your first time contributing, the <a href="./walkthrough.html">walkthrough</a> chapter can give you a good example of
 how a typical contribution would go.</p>
 <p>This documentation is <em>not</em> intended to be comprehensive; it is meant to be a
 quick guide for the most useful things. For more information, <a href="./building/how-to-build-and-run.html">see this
 chapter on how to build and run the compiler</a>.</p>
 <h2 id="asking-questions"><a class="header" href="#asking-questions">Asking Questions</a></h2>
 <p>If you have questions, please make a post on the <a href="https://rust-lang.zulipchat.com">Rust Zulip server</a> or
 <a href="https://internals.rust-lang.org">internals.rust-lang.org</a>. If you are contributing to Rustup, be aware they are not on
 Zulip - you can ask questions in <code>#wg-rustup</code> <a href="http://discord.gg/rust-lang">on Discord</a>.
 See the <a href="https://www.rust-lang.org/governance">list of teams and working groups</a> and <a href="https://www.rust-lang.org/community">the Community page</a> on the
 official website for more resources.</p>
 <p>As a reminder, all contributors are expected to follow our <a href="https://www.rust-lang.org/policies/code-of-conduct">Code of Conduct</a>.</p>
 <p>The compiler team (or <code>t-compiler</code>) usually hangs out in Zulip <a href="https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler">in this
 "stream"</a>; it will be easiest to get questions answered there.</p>
 <p><strong>Please ask questions!</strong> A lot of people report feeling that they are "wasting
 expert time", but nobody on <code>t-compiler</code> feels this way. Contributors are
 important to us.</p>
 <p>Also, if you feel comfortable, prefer public topics, as this means others can
 see the questions and answers, and perhaps even integrate them back into this
 guide :)</p>
 <h3 id="experts"><a class="header" href="#experts">Experts</a></h3>
 <p>Not all <code>t-compiler</code> members are experts on all parts of <code>rustc</code>; it's a
 pretty large project. To find out who could have some expertise on
 different parts of the compiler, <a href="https://github.com/rust-lang/rust/blob/master/triagebot.toml">consult triagebot assign groups</a>.
 The sections that start with <code>[assign*</code> in <code>triagebot.toml</code> file.
 But also, feel free to ask questions even if you can't figure out who to ping.</p>
 <p>Another way to find experts for a given part of the compiler is to see who has made recent commits.
 For example, to find people who have recently worked on name resolution since the 1.68.2 release,
 you could run <code>git shortlog -n 1.68.2.. compiler/rustc_resolve/</code>. Ignore any commits starting with
 "Rollup merge" or commits by <code>@bors</code> (see <a href="./contributing.html#ci">CI contribution procedures</a> for
 more information about these commits).</p>
 <h3 id="etiquette"><a class="header" href="#etiquette">Etiquette</a></h3>
 <p>We do ask that you be mindful to include as much useful information as you can
 in your question, but we recognize this can be hard if you are unfamiliar with
 contributing to Rust.</p>
 <p>Just pinging someone without providing any context can be a bit annoying and
 just create noise, so we ask that you be mindful of the fact that the
 <code>t-compiler</code> folks get a lot of pings in a day.</p>
 <h2 id="what-should-i-work-on"><a class="header" href="#what-should-i-work-on">What should I work on?</a></h2>
 <p>The Rust project is quite large and it can be difficult to know which parts of the project need
 help, or are a good starting place for beginners. Here are some suggested starting places.</p>
 <h3 id="easy-or-mentored-issues"><a class="header" href="#easy-or-mentored-issues">Easy or mentored issues</a></h3>
 <p>If you're looking for somewhere to start, check out the following <a href="https://github.com/issues?q=is%3Aopen+is%3Aissue+org%3Arust-lang+no%3Aassignee+label%3AE-easy%2C%22good+first+issue%22%2Cgood-first-issue%2CE-medium%2CEasy%2CE-help-wanted%2CE-mentor+-label%3AS-blocked+-linked%3Apr+">issue
 search</a>. See the <a href="./contributing.html#issue-triage">Triage</a> for an explanation of these labels. You can also try
 filtering the search to areas you're interested in. For example:</p>
 <ul>
 <li><code>repo:rust-lang/rust-clippy</code> will only show clippy issues</li>
 <li><code>label:T-compiler</code> will only show issues related to the compiler</li>
 <li><code>label:A-diagnostics</code> will only show diagnostic issues</li>
 </ul>
 <p>Not all important or beginner work has issue labels.
 See below for how to find work that isn't labelled.</p>
 <h3 id="recurring-work"><a class="header" href="#recurring-work">Recurring work</a></h3>
 <p>Some work is too large to be done by a single person. In this case, it's common to have "Tracking
 issues" to co-ordinate the work between contributors. Here are some example tracking issues where
 it's easy to pick up work without a large time commitment:</p>
 <ul>
 <li><a href="https://github.com/rust-lang/rust/issues/73494">Move UI tests to subdirectories</a></li>
 </ul>
 <p>If you find more recurring work, please feel free to add it here!</p>
 <h3 id="clippy-issues"><a class="header" href="#clippy-issues">Clippy issues</a></h3>
 <p>The <a href="https://doc.rust-lang.org/clippy/">Clippy</a> project has spent a long time making its contribution process as friendly to newcomers
 as possible. Consider working on it first to get familiar with the process and the compiler
 internals.</p>
 <p>See <a href="https://github.com/rust-lang/rust-clippy/blob/master/CONTRIBUTING.md">the Clippy contribution guide</a> for instructions on getting started.</p>
 <h3 id="diagnostic-issues"><a class="header" href="#diagnostic-issues">Diagnostic issues</a></h3>
 <p>Many diagnostic issues are self-contained and don't need detailed background knowledge of the
 compiler. You can see a list of diagnostic issues <a href="https://github.com/rust-lang/rust/issues?q=is%3Aissue+is%3Aopen+label%3AA-diagnostics+no%3Aassignee">here</a>.</p>
 <h3 id="picking-up-abandoned-pull-requests"><a class="header" href="#picking-up-abandoned-pull-requests">Picking up abandoned pull requests</a></h3>
 <p>Sometimes, contributors send a pull request, but later find out that they don't have enough
 time to work on it, or they simply are not interested in it anymore. Such PRs are often
 eventually closed and they receive the <code>S-inactive</code> label. You could try to examine some of
 these PRs and pick up the work. You can find the list of such PRs <a href="https://github.com/rust-lang/rust/pulls?q=is%3Apr+label%3AS-inactive+is%3Aclosed">here</a>.</p>
 <p>If the PR has been implemented in some other way in the meantime, the <code>S-inactive</code> label
 should be removed from it. If not, and it seems that there is still interest in the change,
 you can try to rebase the pull request on top of the latest <code>master</code> branch and send a new
 pull request, continuing the work on the feature.</p>
 <h3 id="writing-tests"><a class="header" href="#writing-tests">Writing tests</a></h3>
 <p>Issues that have been resolved but do not have a regression test are marked with the <code>E-needs-test</code> label. Writing unit tests is a low-risk, lower-priority task that offers new contributors a great opportunity to familiarize themselves with the testing infrastructure and contribution workflow.</p>
 <h3 id="contributing-to-std-standard-library"><a class="header" href="#contributing-to-std-standard-library">Contributing to std (standard library)</a></h3>
 <p>See <a href="https://std-dev-guide.rust-lang.org/">std-dev-guide</a>.</p>
 <h3 id="contributing-code-to-other-rust-projects"><a class="header" href="#contributing-code-to-other-rust-projects">Contributing code to other Rust projects</a></h3>
 <p>There are a bunch of other projects that you can contribute to outside of the
 <code>rust-lang/rust</code> repo, including <code>cargo</code>, <code>miri</code>, <code>rustup</code>, and many others.</p>
 <p>These repos might have their own contributing guidelines and procedures. Many
 of them are owned by working groups. For more info, see the documentation in those repos' READMEs.</p>
 <h3 id="other-ways-to-contribute"><a class="header" href="#other-ways-to-contribute">Other ways to contribute</a></h3>
 <p>There are a bunch of other ways you can contribute, especially if you don't
 feel comfortable jumping straight into the large <code>rust-lang/rust</code> codebase.</p>
 <p>The following tasks are doable without much background knowledge but are
 incredibly helpful:</p>
 <ul>
 <li><a href="./contributing.html#writing-documentation">Writing documentation</a>: if you are feeling a bit more intrepid, you could try
 to read a part of the code and write doc comments for it. This will help you
 to learn some part of the compiler while also producing a useful artifact!</li>
 <li><a href="./contributing.html#issue-triage">Triaging issues</a>: categorizing, replicating, and minimizing issues is very helpful to the Rust maintainers.</li>
 <li><a href="https://rust-lang.github.io/compiler-team/working-groups/">Working groups</a>: there are a bunch of working groups on a wide variety
 of rust-related things.</li>
 <li>Answer questions in the <em>Get Help!</em> channels on the <a href="http://discord.gg/rust-lang">Rust Discord
 server</a>, on <a href="https://users.rust-lang.org/">users.rust-lang.org</a>, or on
 <a href="http://stackoverflow.com/questions/tagged/rust">StackOverflow</a>.</li>
 <li>Participate in the <a href="https://github.com/rust-lang/rfcs">RFC process</a>.</li>
 <li>Find a <a href="https://github.com/rust-lang/rfcs/labels/A-community-library">requested community library</a>, build it, and publish
 it to <a href="http://crates.io">Crates.io</a>. Easier said than done, but very, very
 valuable!</li>
 </ul>
 <h2 id="cloning-and-building"><a class="header" href="#cloning-and-building">Cloning and Building</a></h2>
 <p>See <a href="./building/how-to-build-and-run.html">"How to build and run the compiler"</a>.</p>
 <h2 id="contributor-procedures"><a class="header" href="#contributor-procedures">Contributor Procedures</a></h2>
 <p>This section has moved to the <a href="./contributing.html">"Contribution Procedures"</a> chapter.</p>
 <h2 id="other-resources"><a class="header" href="#other-resources">Other Resources</a></h2>
 <p>This section has moved to the <a href="./about-this-guide.html#other-places-to-find-information">"About this guide"</a> chapter.</p>

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	<h1 class="menu-title">Rust Compiler Development Guide</h1>

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	<h1 id="getting-started"><a class="header" href="#getting-started">Getting Started</a></h1>
	<p>Thank you for your interest in contributing to Rust! There are many ways to
	contribute, and we appreciate all of them.</p>
	<ul>
	<li><a href="#asking-questions">Asking Questions</a>
	<ul>
	<li><a href="#experts">Experts</a></li>
	<li><a href="#etiquette">Etiquette</a></li>
	</ul>
	</li>
	<li><a href="#what-should-i-work-on">What should I work on?</a>
	<ul>
	<li><a href="#easy-or-mentored-issues">Easy or mentored issues</a></li>
	<li><a href="#recurring-work">Recurring work</a></li>
	<li><a href="#clippy-issues">Clippy issues</a></li>
	<li><a href="#diagnostic-issues">Diagnostic issues</a></li>
	<li><a href="#picking-up-abandoned-pull-requests">Picking up abandoned pull requests</a></li>
	<li><a href="#writing-tests">Writing tests</a></li>
	<li><a href="#contributing-to-std-standard-library">Contributing to std (standard library)</a></li>
	<li><a href="#contributing-code-to-other-rust-projects">Contributing code to other Rust projects</a></li>
	<li><a href="#other-ways-to-contribute">Other ways to contribute</a></li>
	</ul>
	</li>
	<li><a href="#cloning-and-building">Cloning and Building</a></li>
	<li><a href="#contributor-procedures">Contributor Procedures</a></li>
	<li><a href="#other-resources">Other Resources</a></li>
	</ul>
	<p>If this is your first time contributing, the <a href="./walkthrough.html">walkthrough</a> chapter can give you a good example of
	how a typical contribution would go.</p>
	<p>This documentation is <em>not</em> intended to be comprehensive; it is meant to be a
	quick guide for the most useful things. For more information, <a href="./building/how-to-build-and-run.html">see this
	chapter on how to build and run the compiler</a>.</p>
	<h2 id="asking-questions"><a class="header" href="#asking-questions">Asking Questions</a></h2>
	<p>If you have questions, please make a post on the <a href="https://rust-lang.zulipchat.com">Rust Zulip server</a> or
	<a href="https://internals.rust-lang.org">internals.rust-lang.org</a>. If you are contributing to Rustup, be aware they are not on
	Zulip - you can ask questions in <code>#wg-rustup</code> <a href="http://discord.gg/rust-lang">on Discord</a>.
	See the <a href="https://www.rust-lang.org/governance">list of teams and working groups</a> and <a href="https://www.rust-lang.org/community">the Community page</a> on the
	official website for more resources.</p>
	<p>As a reminder, all contributors are expected to follow our <a href="https://www.rust-lang.org/policies/code-of-conduct">Code of Conduct</a>.</p>
	<p>The compiler team (or <code>t-compiler</code>) usually hangs out in Zulip <a href="https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler">in this
	"stream"</a>; it will be easiest to get questions answered there.</p>
	<p><strong>Please ask questions!</strong> A lot of people report feeling that they are "wasting
	expert time", but nobody on <code>t-compiler</code> feels this way. Contributors are
	important to us.</p>
	<p>Also, if you feel comfortable, prefer public topics, as this means others can
	see the questions and answers, and perhaps even integrate them back into this
	guide :)</p>
	<h3 id="experts"><a class="header" href="#experts">Experts</a></h3>
	<p>Not all <code>t-compiler</code> members are experts on all parts of <code>rustc</code>; it's a
	pretty large project. To find out who could have some expertise on
	different parts of the compiler, <a href="https://github.com/rust-lang/rust/blob/master/triagebot.toml">consult triagebot assign groups</a>.
	The sections that start with <code>[assign*</code> in <code>triagebot.toml</code> file.
	But also, feel free to ask questions even if you can't figure out who to ping.</p>
	<p>Another way to find experts for a given part of the compiler is to see who has made recent commits.
	For example, to find people who have recently worked on name resolution since the 1.68.2 release,
	you could run <code>git shortlog -n 1.68.2.. compiler/rustc_resolve/</code>. Ignore any commits starting with
	"Rollup merge" or commits by <code>@bors</code> (see <a href="./contributing.html#ci">CI contribution procedures</a> for
	more information about these commits).</p>
	<h3 id="etiquette"><a class="header" href="#etiquette">Etiquette</a></h3>
	<p>We do ask that you be mindful to include as much useful information as you can
	in your question, but we recognize this can be hard if you are unfamiliar with
	contributing to Rust.</p>
	<p>Just pinging someone without providing any context can be a bit annoying and
	just create noise, so we ask that you be mindful of the fact that the
	<code>t-compiler</code> folks get a lot of pings in a day.</p>
	<h2 id="what-should-i-work-on"><a class="header" href="#what-should-i-work-on">What should I work on?</a></h2>
	<p>The Rust project is quite large and it can be difficult to know which parts of the project need
	help, or are a good starting place for beginners. Here are some suggested starting places.</p>
	<h3 id="easy-or-mentored-issues"><a class="header" href="#easy-or-mentored-issues">Easy or mentored issues</a></h3>
	<p>If you're looking for somewhere to start, check out the following <a href="https://github.com/issues?q=is%3Aopen+is%3Aissue+org%3Arust-lang+no%3Aassignee+label%3AE-easy%2C%22good+first+issue%22%2Cgood-first-issue%2CE-medium%2CEasy%2CE-help-wanted%2CE-mentor+-label%3AS-blocked+-linked%3Apr+">issue
	search</a>. See the <a href="./contributing.html#issue-triage">Triage</a> for an explanation of these labels. You can also try
	filtering the search to areas you're interested in. For example:</p>
	<ul>
	<li><code>repo:rust-lang/rust-clippy</code> will only show clippy issues</li>
	<li><code>label:T-compiler</code> will only show issues related to the compiler</li>
	<li><code>label:A-diagnostics</code> will only show diagnostic issues</li>
	</ul>
	<p>Not all important or beginner work has issue labels.
	See below for how to find work that isn't labelled.</p>
	<h3 id="recurring-work"><a class="header" href="#recurring-work">Recurring work</a></h3>
	<p>Some work is too large to be done by a single person. In this case, it's common to have "Tracking
	issues" to co-ordinate the work between contributors. Here are some example tracking issues where
	it's easy to pick up work without a large time commitment:</p>
	<ul>
	<li><a href="https://github.com/rust-lang/rust/issues/73494">Move UI tests to subdirectories</a></li>
	</ul>
	<p>If you find more recurring work, please feel free to add it here!</p>
	<h3 id="clippy-issues"><a class="header" href="#clippy-issues">Clippy issues</a></h3>
	<p>The <a href="https://doc.rust-lang.org/clippy/">Clippy</a> project has spent a long time making its contribution process as friendly to newcomers
	as possible. Consider working on it first to get familiar with the process and the compiler
	internals.</p>
	<p>See <a href="https://github.com/rust-lang/rust-clippy/blob/master/CONTRIBUTING.md">the Clippy contribution guide</a> for instructions on getting started.</p>
	<h3 id="diagnostic-issues"><a class="header" href="#diagnostic-issues">Diagnostic issues</a></h3>
	<p>Many diagnostic issues are self-contained and don't need detailed background knowledge of the
	compiler. You can see a list of diagnostic issues <a href="https://github.com/rust-lang/rust/issues?q=is%3Aissue+is%3Aopen+label%3AA-diagnostics+no%3Aassignee">here</a>.</p>
	<h3 id="picking-up-abandoned-pull-requests"><a class="header" href="#picking-up-abandoned-pull-requests">Picking up abandoned pull requests</a></h3>
	<p>Sometimes, contributors send a pull request, but later find out that they don't have enough
	time to work on it, or they simply are not interested in it anymore. Such PRs are often
	eventually closed and they receive the <code>S-inactive</code> label. You could try to examine some of
	these PRs and pick up the work. You can find the list of such PRs <a href="https://github.com/rust-lang/rust/pulls?q=is%3Apr+label%3AS-inactive+is%3Aclosed">here</a>.</p>
	<p>If the PR has been implemented in some other way in the meantime, the <code>S-inactive</code> label
	should be removed from it. If not, and it seems that there is still interest in the change,
	you can try to rebase the pull request on top of the latest <code>master</code> branch and send a new
	pull request, continuing the work on the feature.</p>
	<h3 id="writing-tests"><a class="header" href="#writing-tests">Writing tests</a></h3>
	<p>Issues that have been resolved but do not have a regression test are marked with the <code>E-needs-test</code> label. Writing unit tests is a low-risk, lower-priority task that offers new contributors a great opportunity to familiarize themselves with the testing infrastructure and contribution workflow.</p>
	<h3 id="contributing-to-std-standard-library"><a class="header" href="#contributing-to-std-standard-library">Contributing to std (standard library)</a></h3>
	<p>See <a href="https://std-dev-guide.rust-lang.org/">std-dev-guide</a>.</p>
	<h3 id="contributing-code-to-other-rust-projects"><a class="header" href="#contributing-code-to-other-rust-projects">Contributing code to other Rust projects</a></h3>
	<p>There are a bunch of other projects that you can contribute to outside of the
	<code>rust-lang/rust</code> repo, including <code>cargo</code>, <code>miri</code>, <code>rustup</code>, and many others.</p>
	<p>These repos might have their own contributing guidelines and procedures. Many
	of them are owned by working groups. For more info, see the documentation in those repos' READMEs.</p>
	<h3 id="other-ways-to-contribute"><a class="header" href="#other-ways-to-contribute">Other ways to contribute</a></h3>
	<p>There are a bunch of other ways you can contribute, especially if you don't
	feel comfortable jumping straight into the large <code>rust-lang/rust</code> codebase.</p>
	<p>The following tasks are doable without much background knowledge but are
	incredibly helpful:</p>
	<ul>
	<li><a href="./contributing.html#writing-documentation">Writing documentation</a>: if you are feeling a bit more intrepid, you could try
	to read a part of the code and write doc comments for it. This will help you
	to learn some part of the compiler while also producing a useful artifact!</li>
	<li><a href="./contributing.html#issue-triage">Triaging issues</a>: categorizing, replicating, and minimizing issues is very helpful to the Rust maintainers.</li>
	<li><a href="https://rust-lang.github.io/compiler-team/working-groups/">Working groups</a>: there are a bunch of working groups on a wide variety
	of rust-related things.</li>
	<li>Answer questions in the <em>Get Help!</em> channels on the <a href="http://discord.gg/rust-lang">Rust Discord
	server</a>, on <a href="https://users.rust-lang.org/">users.rust-lang.org</a>, or on
	<a href="http://stackoverflow.com/questions/tagged/rust">StackOverflow</a>.</li>
	<li>Participate in the <a href="https://github.com/rust-lang/rfcs">RFC process</a>.</li>
	<li>Find a <a href="https://github.com/rust-lang/rfcs/labels/A-community-library">requested community library</a>, build it, and publish
	it to <a href="http://crates.io">Crates.io</a>. Easier said than done, but very, very
	valuable!</li>
	</ul>
	<h2 id="cloning-and-building"><a class="header" href="#cloning-and-building">Cloning and Building</a></h2>
	<p>See <a href="./building/how-to-build-and-run.html">"How to build and run the compiler"</a>.</p>
	<h2 id="contributor-procedures"><a class="header" href="#contributor-procedures">Contributor Procedures</a></h2>
	<p>This section has moved to the <a href="./contributing.html">"Contribution Procedures"</a> chapter.</p>
	<h2 id="other-resources"><a class="header" href="#other-resources">Other Resources</a></h2>
	<p>This section has moved to the <a href="./about-this-guide.html#other-places-to-find-information">"About this guide"</a> chapter.</p>

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