1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" 2 "http://www.w3.org/TR/html4/strict.dtd"> 3<html> 4<head> 5 <META http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> 6 <title>Clang - Get Involved</title> 7 <link type="text/css" rel="stylesheet" href="menu.css"> 8 <link type="text/css" rel="stylesheet" href="content.css"> 9</head> 10<body> 11 12<!--#include virtual="menu.html.incl"--> 13 14<div id="content"> 15 16<h1>Getting Involved with the Clang Project</h1> 17 18<p>Once you have <a href="get_started.html">checked out and built</a> clang and 19played around with it, you might be wondering what you can do to make it better 20and contribute to its development. Alternatively, maybe you just want to follow 21the development of the project to see it progress. 22</p> 23 24<h2>Contribute</h2> 25 26See the <a href="hacking.html">hacking</a> document for information on how 27to author patches. 28 29<h2>Follow what's going on</h2> 30 31<p>Clang is a subproject of the <a href="https://llvm.org">LLVM Project</a> 32and has a Discourse forum and mailing list:</p> 33 34<ul> 35<li><a href="https://lists.llvm.org/mailman/listinfo/cfe-commits">cfe-commits 36</a> - This list is for patch submission/discussion.</li> 37 38<li><a href="https://discourse.llvm.org/c/clang/6">Clang Frontend Discourse forum</a> - 39This forum is for everything else Clang related (questions and answers, design 40discussions, etc).</li> 41 42</ul> 43 44<p>The most common way to talk with other developers on the project is through 45the <a href="https://discourse.llvm.org/c/clang/6">Clang Frontend Discourse forum 46</a>. The clang forum is a very friendly place and we welcome 47newcomers. In addition to the forum, a significant amount of design 48discussion takes place on the <a 49href="https://lists.llvm.org/mailman/listinfo/cfe-commits">cfe-commits mailing 50list</a>. All of these lists have archives, so you can browse through previous 51discussions or follow the list development on the web if you prefer.</p> 52 53<p>If you're looking for something to work on, check out our <a 54href="OpenProjects.html">Open Projects</a> page or look through the <a 55href="https://github.com/llvm/llvm-project/issues/">LLVM bug tracker</a>.</p> 56 57<h2 id="criteria">Contributing Extensions to Clang</h2> 58 59<p>Clang is designed to support experimentation, 60allowing programmers to easily extend the compiler to support great 61new language features and tools. At some point, the authors of these 62extensions may propose that the extensions become a part of Clang 63itself, to benefit the whole Clang community. However, extensions 64(particularly language extensions) have long-term maintenance costs 65for Clang. The benefits of the extension need to be evaluated against 66these costs. The Clang project uses the following criteria for this 67evaluation:</p> 68 69<ol> 70 <li>Evidence of a significant user community: This is based on a number of 71 factors, including an existing user community, the perceived likelihood that 72 users would adopt such a feature if it were available, and any secondary 73 effects that come from, e.g., a library adopting the feature and providing 74 benefits to its users.</li> 75 76 <li>A specific need to reside within the Clang tree: There are some extensions 77 that would be better expressed as a separate tool, and should remain as 78 separate tools even if they end up being hosted as part of the LLVM umbrella 79 project.</li> 80 81 <li>A specification: The specification must be sufficient to understand the 82 design of the feature as well as interpret the meaning of specific examples. 83 The specification should be detailed enough that another compiler vendor 84 could implement the feature.</li> 85 86 <li>Representation within the appropriate governing organization: For 87 extensions to a language governed by a standards committee (C, C++, OpenCL), 88 the extension itself must have an active proposal and proponent within that 89 committee and have a reasonable chance of acceptance. Clang should drive the 90 standard, not diverge from it. This criterion does not apply to all 91 extensions, since some extensions fall outside of the realm of the standards 92 bodies.</li> 93 94 <li>A long-term support plan: increasingly large or complex extensions to 95 Clang need matching commitments to supporting them over time, including 96 improving their implementation and specification as Clang evolves. The 97 capacity of the contributor to make that commitment is as important as the 98 commitment itself.</li> 99 100 <li>A high-quality implementation: The implementation must fit well into 101 Clang's architecture, follow LLVM's coding conventions, and meet Clang's 102 quality standards, including diagnostics and complete AST 103 representations. This is particularly important for language extensions, 104 because users will learn how those extensions work through the behavior of the 105 compiler.</li> 106 107 <li>A test suite: Extensive testing is crucial to ensure that the language 108 extension is not broken by ongoing maintenance in Clang. The test suite 109 should be complete enough that another compiler vendor could conceivably 110 validate their implementation of the feature against it.</li> 111</ol> 112 113</div> 114</body> 115</html> 116