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<h1 class='fqn'><span class='in-band'>Function <a href='../index.html'>core</a>::<wbr><a href='index.html'>mem</a>::<wbr><a class="fn" href=''>zeroed</a></span><span class='out-of-band'><span class='since' title='Stable since Rust version 1.0.0'>1.0.0</span><span id='render-detail'>
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</span><a class='srclink' href='../../src/core/mem.rs.html#517-519' title='goto source code'>[src]</a></span></h1>
<pre class='rust fn'>pub unsafe fn zeroed<T>() -> T</pre><div class='docblock'><p>Creates a value whose bytes are all zero.</p>
<p>This has the same effect as allocating space with
<a href="fn.uninitialized.html"><code>mem::uninitialized</code></a> and then zeroing it out. It is useful for
<a href="../../book/first-edition/ffi.html">FFI</a> sometimes, but should generally be avoided.</p>
<p>There is no guarantee that an all-zero byte-pattern represents a valid value of
some type <code>T</code>. If <code>T</code> has a destructor and the value is destroyed (due to
a panic or the end of a scope) before being initialized, then the destructor
will run on zeroed data, likely leading to <a href="../../reference/behavior-considered-undefined.html">undefined behavior</a>.</p>
<p>See also the documentation for <a href="fn.uninitialized.html"><code>mem::uninitialized</code></a>, which has
many of the same caveats.</p>
<h1 id="examples" class="section-header"><a href="#examples">Examples</a></h1>
<pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">mem</span>;
<span class="kw">let</span> <span class="ident">x</span>: <span class="ident">i32</span> <span class="op">=</span> <span class="kw">unsafe</span> { <span class="ident">mem</span>::<span class="ident">zeroed</span>() };
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="number">0</span>, <span class="ident">x</span>);<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Amem%3B%0A%0Alet%20x%3A%20i32%20%3D%20unsafe%20%7B%20mem%3A%3Azeroed()%20%7D%3B%0Aassert_eq!(0%2C%20x)%3B%0A%7D">Run</a></pre>
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