blob: 2513cc1baacc7eafc09a0d6191559b61a2ed36d5 [file] [log] [blame] [edit]
<!DOCTYPE html>
<html lang="en" data-content_root="./">
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" /><meta name="viewport" content="width=device-width, initial-scale=1" />
<title>WebAssembly Specification &#8212; WebAssembly 3.0 (2025-10-01)</title>
<link rel="stylesheet" type="text/css" href="_static/pygments.css?v=03e43079" />
<link rel="stylesheet" type="text/css" href="_static/basic.css?v=686e5160" />
<link rel="stylesheet" type="text/css" href="_static/alabaster.css?v=057308f9" />
<script src="_static/documentation_options.js?v=909f528b"></script>
<script src="_static/doctools.js?v=9bcbadda"></script>
<script src="_static/sphinx_highlight.js?v=dc90522c"></script>
<script>window.MathJax = {"tex": {"maxBuffer": 30720, "macros": {"multicolumn": ["", 2]}}, "options": {"menuOptions": {"settings": {"enrich": false}}}}</script>
<script defer="defer" src="https://cdn.jsdelivr.net/npm/mathjax@4/tex-mml-chtml.js"></script>
<link rel="index" title="Index" href="genindex.html" />
<link rel="search" title="Search" href="search.html" />
<link rel="next" title="Introduction" href="intro/index.html" />
<link rel="stylesheet" href="_static/custom.css" type="text/css" />
</head><body>
<div class="document">
<div class="sphinxsidebar" role="navigation" aria-label="Main">
<div class="sphinxsidebarwrapper">
<p class="logo"><a href="#">
<img class="logo" src="_static/webassembly.png" alt="Logo of WebAssembly"/>
</a></p><h3>Navigation</h3>
<ul>
<li class="toctree-l1"><a class="reference internal" href="intro/index.html">Introduction</a></li>
<li class="toctree-l1"><a class="reference internal" href="syntax/index.html">Structure</a></li>
<li class="toctree-l1"><a class="reference internal" href="valid/index.html">Validation</a></li>
<li class="toctree-l1"><a class="reference internal" href="exec/index.html">Execution</a></li>
<li class="toctree-l1"><a class="reference internal" href="binary/index.html">Binary Format</a></li>
<li class="toctree-l1"><a class="reference internal" href="text/index.html">Text Format</a></li>
<li class="toctree-l1"><a class="reference internal" href="appendix/index.html">Appendix</a></li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="appendix/index-types.html">Index of Types</a></li>
<li class="toctree-l1"><a class="reference internal" href="appendix/index-instructions.html">Index of Instructions</a></li>
<li class="toctree-l1"><a class="reference internal" href="appendix/index-rules.html">Index of Semantic Rules</a></li>
</ul>
<hr />
<ul>
<li class="toctree-l1"><a href="./genindex.html">Index</a></li>
<li class="toctree-l1"><a href="./_download/WebAssembly.pdf">Download as PDF</a></li>
</ul>
<search id="searchbox" style="display: none" role="search">
<h3 id="searchlabel">Quick search</h3>
<div class="searchformwrapper">
<form class="search" action="search.html" method="get">
<input type="text" name="q" aria-labelledby="searchlabel" autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false"/>
<input type="submit" value="Go" />
</form>
</div>
</search>
<script>document.getElementById('searchbox').style.display = "block"</script>
</div>
</div>
<div class="documentwrapper">
<div class="bodywrapper">
<div class="body" role="main">
<section id="webassembly-specification">
<h1>WebAssembly Specification<a class="headerlink" href="#webassembly-specification" title="Link to this heading">ΒΆ</a></h1>
<div class="line-block">
<div class="line">Release 3.0 (2025-10-01)</div>
</div>
<div class="line-block">
<div class="line">Editor: Andreas Rossberg</div>
</div>
<div class="line-block">
<div class="line">Latest Draft: <a class="reference external" href="https://webassembly.github.io/spec/core/">https://webassembly.github.io/spec/core/</a></div>
<div class="line">Issue Tracker: <a class="reference external" href="https://github.com/webassembly/spec/issues/">https://github.com/webassembly/spec/issues/</a></div>
</div>
<div class="toctree-wrapper compound">
<ul>
<li class="toctree-l1"><a class="reference internal" href="intro/index.html">Introduction</a><ul>
<li class="toctree-l2"><a class="reference internal" href="intro/introduction.html">Introduction</a></li>
<li class="toctree-l2"><a class="reference internal" href="intro/overview.html">Overview</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="syntax/index.html">Structure</a><ul>
<li class="toctree-l2"><a class="reference internal" href="syntax/conventions.html">Conventions</a></li>
<li class="toctree-l2"><a class="reference internal" href="syntax/values.html">Values</a></li>
<li class="toctree-l2"><a class="reference internal" href="syntax/types.html">Types</a></li>
<li class="toctree-l2"><a class="reference internal" href="syntax/instructions.html">Instructions</a></li>
<li class="toctree-l2"><a class="reference internal" href="syntax/modules.html">Modules</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="valid/index.html">Validation</a><ul>
<li class="toctree-l2"><a class="reference internal" href="valid/conventions.html">Conventions</a></li>
<li class="toctree-l2"><a class="reference internal" href="valid/types.html">Types</a></li>
<li class="toctree-l2"><a class="reference internal" href="valid/matching.html">Matching</a></li>
<li class="toctree-l2"><a class="reference internal" href="valid/instructions.html">Instructions</a></li>
<li class="toctree-l2"><a class="reference internal" href="valid/modules.html">Modules</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="exec/index.html">Execution</a><ul>
<li class="toctree-l2"><a class="reference internal" href="exec/conventions.html">Conventions</a></li>
<li class="toctree-l2"><a class="reference internal" href="exec/runtime.html">Runtime Structure</a></li>
<li class="toctree-l2"><a class="reference internal" href="exec/numerics.html">Numerics</a></li>
<li class="toctree-l2"><a class="reference internal" href="exec/types.html">Types</a></li>
<li class="toctree-l2"><a class="reference internal" href="exec/values.html">Values</a></li>
<li class="toctree-l2"><a class="reference internal" href="exec/instructions.html">Instructions</a></li>
<li class="toctree-l2"><a class="reference internal" href="exec/modules.html">Modules</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="binary/index.html">Binary Format</a><ul>
<li class="toctree-l2"><a class="reference internal" href="binary/conventions.html">Conventions</a></li>
<li class="toctree-l2"><a class="reference internal" href="binary/values.html">Values</a></li>
<li class="toctree-l2"><a class="reference internal" href="binary/types.html">Types</a></li>
<li class="toctree-l2"><a class="reference internal" href="binary/instructions.html">Instructions</a></li>
<li class="toctree-l2"><a class="reference internal" href="binary/modules.html">Modules</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="text/index.html">Text Format</a><ul>
<li class="toctree-l2"><a class="reference internal" href="text/conventions.html">Conventions</a></li>
<li class="toctree-l2"><a class="reference internal" href="text/lexical.html">Lexical Format</a></li>
<li class="toctree-l2"><a class="reference internal" href="text/values.html">Values</a></li>
<li class="toctree-l2"><a class="reference internal" href="text/types.html">Types</a></li>
<li class="toctree-l2"><a class="reference internal" href="text/instructions.html">Instructions</a></li>
<li class="toctree-l2"><a class="reference internal" href="text/modules.html">Modules</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="appendix/index.html">Appendix</a><ul>
<li class="toctree-l2"><a class="reference internal" href="appendix/embedding.html">Embedding</a></li>
<li class="toctree-l2"><a class="reference internal" href="appendix/profiles.html">Profiles</a></li>
<li class="toctree-l2"><a class="reference internal" href="appendix/implementation.html">Implementation Limitations</a></li>
<li class="toctree-l2"><a class="reference internal" href="appendix/properties.html">Type Soundness</a></li>
<li class="toctree-l2"><a class="reference internal" href="appendix/properties.html#type-system-properties">Type System Properties</a></li>
<li class="toctree-l2"><a class="reference internal" href="appendix/algorithm.html">Validation Algorithm</a></li>
<li class="toctree-l2"><a class="reference internal" href="appendix/custom.html">Custom Sections and Annotations</a></li>
<li class="toctree-l2"><a class="reference internal" href="appendix/changes.html">Change History</a></li>
<li class="toctree-l2"><a class="reference internal" href="appendix/index-types.html">Index of Types</a></li>
<li class="toctree-l2"><a class="reference internal" href="appendix/index-instructions.html">Index of Instructions</a></li>
<li class="toctree-l2"><a class="reference internal" href="appendix/index-rules.html">Index of Semantic Rules</a></li>
</ul>
</li>
</ul>
</div>
<ul class="simple">
<li><p><a class="reference internal" href="appendix/index-types.html#index-type"><span class="std std-ref">Index of Types</span></a></p></li>
<li><p><a class="reference internal" href="appendix/index-instructions.html#index-instr"><span class="std std-ref">Index of Instructions</span></a></p></li>
<li><p><a class="reference internal" href="appendix/index-rules.html#index-rules"><span class="std std-ref">Index of Semantic Rules</span></a></p></li>
<li><p><a class="reference internal" href="genindex.html"><span class="std std-ref">Index</span></a></p></li>
</ul>
</section>
</div>
</div>
</div>
<div class="clearer"></div>
</div>
<div class="footer">
&#169;2017-2025, WebAssembly Community Group.
</div>
</body>
</html>