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| 22 | <title>Integer Conversion (GNU C Language Manual)</title>
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| 23 |
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| 30 | <link href="Symbol-Index.html" rel="index" title="Symbol Index">
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| 31 | <link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
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| 32 | <link href="Integer-Types.html" rel="up" title="Integer Types">
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| 33 | <link href="Boolean-Type.html" rel="next" title="Boolean Type">
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| 34 | <link href="Narrow-Integers.html" rel="prev" title="Narrow Integers">
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| 55 | </head>
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| 56 |
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| 57 | <body lang="en">
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| 58 | <span id="Integer-Conversion"></span><div class="header">
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| 59 | <p>
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| 60 | Next: <a href="Boolean-Type.html" accesskey="n" rel="next">Boolean Type</a>, Previous: <a href="Narrow-Integers.html" accesskey="p" rel="prev">Narrow Integers</a>, Up: <a href="Integer-Types.html" accesskey="u" rel="up">Integer Types</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Symbol-Index.html" title="Index" rel="index">Index</a>]</p>
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| 61 | </div>
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| 62 | <hr>
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| 63 | <span id="Conversion-among-Integer-Types"></span><h4 class="subsection">11.1.4 Conversion among Integer Types</h4>
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| 64 |
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| 65 | <p>C converts between integer types implicitly in many situations. It
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| 66 | converts the narrow integer types, <code>char</code> and <code>short</code>, to
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| 67 | <code>int</code> whenever they are used in arithmetic. Assigning a new
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| 68 | value to an integer variable (or other lvalue) converts the value to
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| 69 | the variable’s type.
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| 70 | </p>
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| 71 | <p>You can also convert one integer type to another explicitly with a
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| 72 | <em>cast</em> operator. See <a href="Explicit-Type-Conversion.html">Explicit Type Conversion</a>.
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| 73 | </p>
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| 74 | <p>The process of conversion to a wider type is straightforward: the
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| 75 | value is unchanged. The only exception is when converting a negative
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| 76 | value (in a signed type, obviously) to a wider unsigned type. In that
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| 77 | case, the result is a positive value with the same bits
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| 78 | (see <a href="Integers-in-Depth.html">Integers in Depth</a>).
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| 79 | </p>
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| 80 | <span id="index-truncation"></span>
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| 81 | <p>Converting to a narrower type, also called <em>truncation</em>, involves
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| 82 | discarding some of the value’s bits. This is not considered overflow
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| 83 | (see <a href="Integer-Overflow.html">Integer Overflow</a>) because loss of significant bits is a
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| 84 | normal consequence of truncation. Likewise for conversion between
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| 85 | signed and unsigned types of the same width.
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| 86 | </p>
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| 87 | <p>More information about conversion for assignment is in
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| 88 | <a href="Assignment-Type-Conversions.html">Assignment Type Conversions</a>. For conversion for arithmetic,
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| 89 | see <a href="Argument-Promotions.html">Argument Promotions</a>.
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| 90 | </p>
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| 91 |
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| 92 |
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| 93 |
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| 94 | </body>
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| 95 | </html>
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