Mini Kabibi Habibi
<!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" />
<meta property="og:title" content="Allocating Objects on the Heap" />
<meta property="og:type" content="website" />
<meta property="og:url" content="https://docs.python.org/3/c-api/allocation.html" />
<meta property="og:site_name" content="Python documentation" />
<meta property="og:image" content="_static/og-image.png" />
<meta property="og:image:alt" content="Python documentation" />
<meta name="theme-color" content="#3776ab">
<meta property="og:image:width" content="200">
<meta property="og:image:height" content="200">
<title>Allocating Objects on the Heap — Python 3.14.0 documentation</title><meta name="viewport" content="width=device-width, initial-scale=1.0">
<link rel="stylesheet" type="text/css" href="../_static/pygments.css?v=b86133f3" />
<link rel="stylesheet" type="text/css" href="../_static/classic.css?v=234b1a7c" />
<link rel="stylesheet" type="text/css" href="../_static/pydoctheme.css?v=8cd84f99" />
<link id="pygments_dark_css" media="(prefers-color-scheme: dark)" rel="stylesheet" type="text/css" href="../_static/pygments_dark.css?v=5349f25f" />
<script src="../_static/documentation_options.js?v=e4f4b189"></script>
<script src="../_static/doctools.js?v=9bcbadda"></script>
<script src="../_static/sphinx_highlight.js?v=dc90522c"></script>
<script src="../_static/sidebar.js"></script>
<link rel="search" type="application/opensearchdescription+xml"
title="Search within Python 3.14.0 documentation"
href="../_static/opensearch.xml"/>
<link rel="author" title="About these documents" href="../about.html" />
<link rel="index" title="Index" href="../genindex.html" />
<link rel="search" title="Search" href="../search.html" />
<link rel="copyright" title="Copyright" href="../copyright.html" />
<link rel="next" title="Object Life Cycle" href="lifecycle.html" />
<link rel="prev" title="Object Implementation Support" href="objimpl.html" />
<link rel="canonical" href="https://docs.python.org/3/c-api/allocation.html">
<style>
@media only screen {
table.full-width-table {
width: 100%;
}
}
</style>
<link rel="stylesheet" href="../_static/pydoctheme_dark.css" media="(prefers-color-scheme: dark)" id="pydoctheme_dark_css">
<link rel="shortcut icon" type="image/png" href="../_static/py.svg">
<script type="text/javascript" src="../_static/copybutton.js"></script>
<script type="text/javascript" src="../_static/menu.js"></script>
<script type="text/javascript" src="../_static/search-focus.js"></script>
<script type="text/javascript" src="../_static/themetoggle.js"></script>
<script type="text/javascript" src="../_static/rtd_switcher.js"></script>
<meta name="readthedocs-addons-api-version" content="1">
</head>
<body>
<div class="mobile-nav">
<input type="checkbox" id="menuToggler" class="toggler__input" aria-controls="navigation"
aria-pressed="false" aria-expanded="false" role="button" aria-label="Menu">
<nav class="nav-content" role="navigation">
<label for="menuToggler" class="toggler__label">
<span></span>
</label>
<span class="nav-items-wrapper">
<a href="https://www.python.org/" class="nav-logo">
<img src="../_static/py.svg" alt="Python logo">
</a>
<span class="version_switcher_placeholder"></span>
<form role="search" class="search" action="../search.html" method="get">
<svg xmlns="http://www.w3.org/2000/svg" width="20" height="20" viewBox="0 0 24 24" class="search-icon">
<path fill-rule="nonzero" fill="currentColor" d="M15.5 14h-.79l-.28-.27a6.5 6.5 0 001.48-5.34c-.47-2.78-2.79-5-5.59-5.34a6.505 6.505 0 00-7.27 7.27c.34 2.8 2.56 5.12 5.34 5.59a6.5 6.5 0 005.34-1.48l.27.28v.79l4.25 4.25c.41.41 1.08.41 1.49 0 .41-.41.41-1.08 0-1.49L15.5 14zm-6 0C7.01 14 5 11.99 5 9.5S7.01 5 9.5 5 14 7.01 14 9.5 11.99 14 9.5 14z"></path>
</svg>
<input placeholder="Quick search" aria-label="Quick search" type="search" name="q">
<input type="submit" value="Go">
</form>
</span>
</nav>
<div class="menu-wrapper">
<nav class="menu" role="navigation" aria-label="main navigation">
<div class="language_switcher_placeholder"></div>
<label class="theme-selector-label">
Theme
<select class="theme-selector" oninput="activateTheme(this.value)">
<option value="auto" selected>Auto</option>
<option value="light">Light</option>
<option value="dark">Dark</option>
</select>
</label>
<div>
<h4>Previous topic</h4>
<p class="topless"><a href="objimpl.html"
title="previous chapter">Object Implementation Support</a></p>
</div>
<div>
<h4>Next topic</h4>
<p class="topless"><a href="lifecycle.html"
title="next chapter">Object Life Cycle</a></p>
</div>
<div role="note" aria-label="source link">
<h3>This page</h3>
<ul class="this-page-menu">
<li><a href="../bugs.html">Report a bug</a></li>
<li>
<a href="https://github.com/python/cpython/blob/main/Doc/c-api/allocation.rst?plain=1"
rel="nofollow">Show source
</a>
</li>
</ul>
</div>
</nav>
</div>
</div>
<div class="related" role="navigation" aria-label="Related">
<h3>Navigation</h3>
<ul>
<li class="right" style="margin-right: 10px">
<a href="../genindex.html" title="General Index"
accesskey="I">index</a></li>
<li class="right" >
<a href="../py-modindex.html" title="Python Module Index"
>modules</a> |</li>
<li class="right" >
<a href="lifecycle.html" title="Object Life Cycle"
accesskey="N">next</a> |</li>
<li class="right" >
<a href="objimpl.html" title="Object Implementation Support"
accesskey="P">previous</a> |</li>
<li><img src="../_static/py.svg" alt="Python logo" style="vertical-align: middle; margin-top: -1px"></li>
<li><a href="https://www.python.org/">Python</a> »</li>
<li class="switchers">
<div class="language_switcher_placeholder"></div>
<div class="version_switcher_placeholder"></div>
</li>
<li>
</li>
<li id="cpython-language-and-version">
<a href="../index.html">3.14.0 Documentation</a> »
</li>
<li class="nav-item nav-item-1"><a href="index.html" >Python/C API Reference Manual</a> »</li>
<li class="nav-item nav-item-2"><a href="objimpl.html" accesskey="U">Object Implementation Support</a> »</li>
<li class="nav-item nav-item-this"><a href="">Allocating Objects on the Heap</a></li>
<li class="right">
<div class="inline-search" role="search">
<form class="inline-search" action="../search.html" method="get">
<input placeholder="Quick search" aria-label="Quick search" type="search" name="q" id="search-box">
<input type="submit" value="Go">
</form>
</div>
|
</li>
<li class="right">
<label class="theme-selector-label">
Theme
<select class="theme-selector" oninput="activateTheme(this.value)">
<option value="auto" selected>Auto</option>
<option value="light">Light</option>
<option value="dark">Dark</option>
</select>
</label> |</li>
</ul>
</div>
<div class="document">
<div class="documentwrapper">
<div class="bodywrapper">
<div class="body" role="main">
<section id="allocating-objects-on-the-heap">
<span id="allocating-objects"></span><h1>Allocating Objects on the Heap<a class="headerlink" href="#allocating-objects-on-the-heap" title="Link to this heading">¶</a></h1>
<dl class="c function">
<dt class="sig sig-object c" id="c._PyObject_New">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="sig-name descname"><span class="n"><span class="pre">_PyObject_New</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><span class="n"><span class="pre">PyTypeObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">type</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c._PyObject_New" title="Link to this definition">¶</a><br /></dt>
<dd><em class="refcount return_new_ref">Return value: New reference.</em></dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c._PyObject_NewVar">
<a class="reference internal" href="structures.html#c.PyVarObject" title="PyVarObject"><span class="n"><span class="pre">PyVarObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="sig-name descname"><span class="n"><span class="pre">_PyObject_NewVar</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><span class="n"><span class="pre">PyTypeObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">type</span></span>, <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><span class="n"><span class="pre">Py_ssize_t</span></span></a><span class="w"> </span><span class="n"><span class="pre">size</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c._PyObject_NewVar" title="Link to this definition">¶</a><br /></dt>
<dd><em class="refcount return_new_ref">Return value: New reference.</em></dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyObject_Init">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="sig-name descname"><span class="n"><span class="pre">PyObject_Init</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">op</span></span>, <a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><span class="n"><span class="pre">PyTypeObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">type</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Init" title="Link to this definition">¶</a><br /></dt>
<dd><em class="refcount return_borrowed_ref">Return value: Borrowed reference.</em><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em><p>Initialize a newly allocated object <em>op</em> with its type and initial
reference. Returns the initialized object. Other fields of the object are
not initialized. Despite its name, this function is unrelated to the
object’s <a class="reference internal" href="../reference/datamodel.html#object.__init__" title="object.__init__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__init__()</span></code></a> method (<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_init" title="PyTypeObject.tp_init"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_init</span></code></a>
slot). Specifically, this function does <strong>not</strong> call the object’s
<code class="xref py py-meth docutils literal notranslate"><span class="pre">__init__()</span></code> method.</p>
<p>In general, consider this function to be a low-level routine. Use
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_alloc" title="PyTypeObject.tp_alloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_alloc</span></code></a> where possible.
For implementing <code class="xref c c-member docutils literal notranslate"><span class="pre">tp_alloc</span></code> for your type, prefer
<a class="reference internal" href="type.html#c.PyType_GenericAlloc" title="PyType_GenericAlloc"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyType_GenericAlloc()</span></code></a> or <a class="reference internal" href="#c.PyObject_New" title="PyObject_New"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_New()</span></code></a>.</p>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>This function only initializes the object’s memory corresponding to the
initial <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyObject</span></code></a> structure. It does not zero the rest.</p>
</div>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyObject_InitVar">
<a class="reference internal" href="structures.html#c.PyVarObject" title="PyVarObject"><span class="n"><span class="pre">PyVarObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="sig-name descname"><span class="n"><span class="pre">PyObject_InitVar</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyVarObject" title="PyVarObject"><span class="n"><span class="pre">PyVarObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">op</span></span>, <a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><span class="n"><span class="pre">PyTypeObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">type</span></span>, <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><span class="n"><span class="pre">Py_ssize_t</span></span></a><span class="w"> </span><span class="n"><span class="pre">size</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_InitVar" title="Link to this definition">¶</a><br /></dt>
<dd><em class="refcount return_borrowed_ref">Return value: Borrowed reference.</em><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em><p>This does everything <a class="reference internal" href="#c.PyObject_Init" title="PyObject_Init"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_Init()</span></code></a> does, and also initializes the
length information for a variable-size object.</p>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>This function only initializes some of the object’s memory. It does not
zero the rest.</p>
</div>
</dd></dl>
<dl class="c macro">
<dt class="sig sig-object c" id="c.PyObject_New">
<span class="sig-name descname"><span class="n"><span class="pre">PyObject_New</span></span></span><span class="sig-paren">(</span><span class="n"><span class="pre">TYPE</span></span>, <span class="n"><span class="pre">typeobj</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_New" title="Link to this definition">¶</a><br /></dt>
<dd><p>Allocates a new Python object using the C structure type <em>TYPE</em> and the
Python type object <em>typeobj</em> (<code class="docutils literal notranslate"><span class="pre">PyTypeObject*</span></code>) by calling
<a class="reference internal" href="memory.html#c.PyObject_Malloc" title="PyObject_Malloc"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_Malloc()</span></code></a> to allocate memory and initializing it like
<a class="reference internal" href="#c.PyObject_Init" title="PyObject_Init"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_Init()</span></code></a>. The caller will own the only reference to the
object (i.e. its reference count will be one).</p>
<p>Avoid calling this directly to allocate memory for an object; call the type’s
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_alloc" title="PyTypeObject.tp_alloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_alloc</span></code></a> slot instead.</p>
<p>When populating a type’s <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_alloc" title="PyTypeObject.tp_alloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_alloc</span></code></a> slot,
<a class="reference internal" href="type.html#c.PyType_GenericAlloc" title="PyType_GenericAlloc"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyType_GenericAlloc()</span></code></a> is preferred over a custom function that
simply calls this macro.</p>
<p>This macro does not call <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_alloc" title="PyTypeObject.tp_alloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_alloc</span></code></a>,
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_new" title="PyTypeObject.tp_new"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_new</span></code></a> (<a class="reference internal" href="../reference/datamodel.html#object.__new__" title="object.__new__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__new__()</span></code></a>), or
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_init" title="PyTypeObject.tp_init"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_init</span></code></a> (<a class="reference internal" href="../reference/datamodel.html#object.__init__" title="object.__init__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__init__()</span></code></a>).</p>
<p>This cannot be used for objects with <a class="reference internal" href="typeobj.html#c.Py_TPFLAGS_HAVE_GC" title="Py_TPFLAGS_HAVE_GC"><code class="xref c c-macro docutils literal notranslate"><span class="pre">Py_TPFLAGS_HAVE_GC</span></code></a> set in
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_flags" title="PyTypeObject.tp_flags"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_flags</span></code></a>; use <a class="reference internal" href="gcsupport.html#c.PyObject_GC_New" title="PyObject_GC_New"><code class="xref c c-macro docutils literal notranslate"><span class="pre">PyObject_GC_New</span></code></a> instead.</p>
<p>Memory allocated by this macro must be freed with <a class="reference internal" href="memory.html#c.PyObject_Free" title="PyObject_Free"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_Free()</span></code></a>
(usually called via the object’s <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_free" title="PyTypeObject.tp_free"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_free</span></code></a> slot).</p>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>The returned memory is not guaranteed to have been completely zeroed
before it was initialized.</p>
</div>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>This macro does not construct a fully initialized object of the given
type; it merely allocates memory and prepares it for further
initialization by <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_init" title="PyTypeObject.tp_init"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_init</span></code></a>. To construct a
fully initialized object, call <em>typeobj</em> instead. For example:</p>
<div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="n">PyObject</span><span class="w"> </span><span class="o">*</span><span class="n">foo</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">PyObject_CallNoArgs</span><span class="p">((</span><span class="n">PyObject</span><span class="w"> </span><span class="o">*</span><span class="p">)</span><span class="o">&</span><span class="n">PyFoo_Type</span><span class="p">);</span>
</pre></div>
</div>
</div>
<div class="admonition seealso">
<p class="admonition-title">See also</p>
<ul class="simple">
<li><p><a class="reference internal" href="memory.html#c.PyObject_Free" title="PyObject_Free"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_Free()</span></code></a></p></li>
<li><p><a class="reference internal" href="gcsupport.html#c.PyObject_GC_New" title="PyObject_GC_New"><code class="xref c c-macro docutils literal notranslate"><span class="pre">PyObject_GC_New</span></code></a></p></li>
<li><p><a class="reference internal" href="type.html#c.PyType_GenericAlloc" title="PyType_GenericAlloc"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyType_GenericAlloc()</span></code></a></p></li>
<li><p><a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_alloc" title="PyTypeObject.tp_alloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_alloc</span></code></a></p></li>
</ul>
</div>
</dd></dl>
<dl class="c macro">
<dt class="sig sig-object c" id="c.PyObject_NewVar">
<span class="sig-name descname"><span class="n"><span class="pre">PyObject_NewVar</span></span></span><span class="sig-paren">(</span><span class="n"><span class="pre">TYPE</span></span>, <span class="n"><span class="pre">typeobj</span></span>, <span class="n"><span class="pre">size</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_NewVar" title="Link to this definition">¶</a><br /></dt>
<dd><p>Like <a class="reference internal" href="#c.PyObject_New" title="PyObject_New"><code class="xref c c-macro docutils literal notranslate"><span class="pre">PyObject_New</span></code></a> except:</p>
<ul class="simple">
<li><p>It allocates enough memory for the <em>TYPE</em> structure plus <em>size</em>
(<code class="docutils literal notranslate"><span class="pre">Py_ssize_t</span></code>) fields of the size given by the
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_itemsize" title="PyTypeObject.tp_itemsize"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_itemsize</span></code></a> field of <em>typeobj</em>.</p></li>
<li><p>The memory is initialized like <a class="reference internal" href="#c.PyObject_InitVar" title="PyObject_InitVar"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_InitVar()</span></code></a>.</p></li>
</ul>
<p>This is useful for implementing objects like tuples, which are able to
determine their size at construction time. Embedding the array of fields
into the same allocation decreases the number of allocations, improving the
memory management efficiency.</p>
<p>Avoid calling this directly to allocate memory for an object; call the type’s
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_alloc" title="PyTypeObject.tp_alloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_alloc</span></code></a> slot instead.</p>
<p>When populating a type’s <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_alloc" title="PyTypeObject.tp_alloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_alloc</span></code></a> slot,
<a class="reference internal" href="type.html#c.PyType_GenericAlloc" title="PyType_GenericAlloc"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyType_GenericAlloc()</span></code></a> is preferred over a custom function that
simply calls this macro.</p>
<p>This cannot be used for objects with <a class="reference internal" href="typeobj.html#c.Py_TPFLAGS_HAVE_GC" title="Py_TPFLAGS_HAVE_GC"><code class="xref c c-macro docutils literal notranslate"><span class="pre">Py_TPFLAGS_HAVE_GC</span></code></a> set in
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_flags" title="PyTypeObject.tp_flags"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_flags</span></code></a>; use <a class="reference internal" href="gcsupport.html#c.PyObject_GC_NewVar" title="PyObject_GC_NewVar"><code class="xref c c-macro docutils literal notranslate"><span class="pre">PyObject_GC_NewVar</span></code></a>
instead.</p>
<p>Memory allocated by this function must be freed with <a class="reference internal" href="memory.html#c.PyObject_Free" title="PyObject_Free"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_Free()</span></code></a>
(usually called via the object’s <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_free" title="PyTypeObject.tp_free"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_free</span></code></a> slot).</p>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>The returned memory is not guaranteed to have been completely zeroed
before it was initialized.</p>
</div>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>This macro does not construct a fully initialized object of the given
type; it merely allocates memory and prepares it for further
initialization by <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_init" title="PyTypeObject.tp_init"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_init</span></code></a>. To construct a
fully initialized object, call <em>typeobj</em> instead. For example:</p>
<div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="n">PyObject</span><span class="w"> </span><span class="o">*</span><span class="n">list_instance</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">PyObject_CallNoArgs</span><span class="p">((</span><span class="n">PyObject</span><span class="w"> </span><span class="o">*</span><span class="p">)</span><span class="o">&</span><span class="n">PyList_Type</span><span class="p">);</span>
</pre></div>
</div>
</div>
<div class="admonition seealso">
<p class="admonition-title">See also</p>
<ul class="simple">
<li><p><a class="reference internal" href="memory.html#c.PyObject_Free" title="PyObject_Free"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_Free()</span></code></a></p></li>
<li><p><a class="reference internal" href="gcsupport.html#c.PyObject_GC_NewVar" title="PyObject_GC_NewVar"><code class="xref c c-macro docutils literal notranslate"><span class="pre">PyObject_GC_NewVar</span></code></a></p></li>
<li><p><a class="reference internal" href="type.html#c.PyType_GenericAlloc" title="PyType_GenericAlloc"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyType_GenericAlloc()</span></code></a></p></li>
<li><p><a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_alloc" title="PyTypeObject.tp_alloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_alloc</span></code></a></p></li>
</ul>
</div>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyObject_Del">
<span class="kt"><span class="pre">void</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyObject_Del</span></span></span><span class="sig-paren">(</span><span class="kt"><span class="pre">void</span></span><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">op</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_Del" title="Link to this definition">¶</a><br /></dt>
<dd><p>Same as <a class="reference internal" href="memory.html#c.PyObject_Free" title="PyObject_Free"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_Free()</span></code></a>.</p>
</dd></dl>
<dl class="c var">
<dt class="sig sig-object c" id="c._Py_NoneStruct">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">_Py_NoneStruct</span></span></span><a class="headerlink" href="#c._Py_NoneStruct" title="Link to this definition">¶</a><br /></dt>
<dd><p>Object which is visible in Python as <code class="docutils literal notranslate"><span class="pre">None</span></code>. This should only be accessed
using the <a class="reference internal" href="none.html#c.Py_None" title="Py_None"><code class="xref c c-macro docutils literal notranslate"><span class="pre">Py_None</span></code></a> macro, which evaluates to a pointer to this
object.</p>
</dd></dl>
<div class="admonition seealso">
<p class="admonition-title">See also</p>
<dl class="simple">
<dt><a class="reference internal" href="module.html#moduleobjects"><span class="std std-ref">Module Objects</span></a></dt><dd><p>To allocate and create extension modules.</p>
</dd>
</dl>
</div>
</section>
<div class="clearer"></div>
</div>
</div>
</div>
<div class="sphinxsidebar" role="navigation" aria-label="Main">
<div class="sphinxsidebarwrapper">
<div>
<h4>Previous topic</h4>
<p class="topless"><a href="objimpl.html"
title="previous chapter">Object Implementation Support</a></p>
</div>
<div>
<h4>Next topic</h4>
<p class="topless"><a href="lifecycle.html"
title="next chapter">Object Life Cycle</a></p>
</div>
<div role="note" aria-label="source link">
<h3>This page</h3>
<ul class="this-page-menu">
<li><a href="../bugs.html">Report a bug</a></li>
<li>
<a href="https://github.com/python/cpython/blob/main/Doc/c-api/allocation.rst?plain=1"
rel="nofollow">Show source
</a>
</li>
</ul>
</div>
</div>
<div id="sidebarbutton" title="Collapse sidebar">
<span>«</span>
</div>
</div>
<div class="clearer"></div>
</div>
<div class="related" role="navigation" aria-label="Related">
<h3>Navigation</h3>
<ul>
<li class="right" style="margin-right: 10px">
<a href="../genindex.html" title="General Index"
>index</a></li>
<li class="right" >
<a href="../py-modindex.html" title="Python Module Index"
>modules</a> |</li>
<li class="right" >
<a href="lifecycle.html" title="Object Life Cycle"
>next</a> |</li>
<li class="right" >
<a href="objimpl.html" title="Object Implementation Support"
>previous</a> |</li>
<li><img src="../_static/py.svg" alt="Python logo" style="vertical-align: middle; margin-top: -1px"></li>
<li><a href="https://www.python.org/">Python</a> »</li>
<li class="switchers">
<div class="language_switcher_placeholder"></div>
<div class="version_switcher_placeholder"></div>
</li>
<li>
</li>
<li id="cpython-language-and-version">
<a href="../index.html">3.14.0 Documentation</a> »
</li>
<li class="nav-item nav-item-1"><a href="index.html" >Python/C API Reference Manual</a> »</li>
<li class="nav-item nav-item-2"><a href="objimpl.html" >Object Implementation Support</a> »</li>
<li class="nav-item nav-item-this"><a href="">Allocating Objects on the Heap</a></li>
<li class="right">
<div class="inline-search" role="search">
<form class="inline-search" action="../search.html" method="get">
<input placeholder="Quick search" aria-label="Quick search" type="search" name="q" id="search-box">
<input type="submit" value="Go">
</form>
</div>
|
</li>
<li class="right">
<label class="theme-selector-label">
Theme
<select class="theme-selector" oninput="activateTheme(this.value)">
<option value="auto" selected>Auto</option>
<option value="light">Light</option>
<option value="dark">Dark</option>
</select>
</label> |</li>
</ul>
</div>
<div class="footer">
© <a href="../copyright.html">Copyright</a> 2001 Python Software Foundation.
<br>
This page is licensed under the Python Software Foundation License Version 2.
<br>
Examples, recipes, and other code in the documentation are additionally licensed under the Zero Clause BSD License.
<br>
See <a href="/license.html">History and License</a> for more information.<br>
<br>
The Python Software Foundation is a non-profit corporation.
<a href="https://www.python.org/psf/donations/">Please donate.</a>
<br>
<br>
Last updated on Oct 07, 2025 (10:02 UTC).
<a href="/bugs.html">Found a bug</a>?
<br>
Created using <a href="https://www.sphinx-doc.org/">Sphinx</a> 8.2.3.
</div>
</body>
</html>