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| 22 | <title>Common Type (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="Type-Conversions.html" rel="up" title="Type Conversions">
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| 33 | <link href="Scope.html" rel="next" title="Scope">
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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="Common-Type"></span><div class="header">
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| 59 | <p>
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| 60 | Previous: <a href="Operand-Promotions.html" accesskey="p" rel="prev">Operand Promotions</a>, Up: <a href="Type-Conversions.html" accesskey="u" rel="up">Type Conversions</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="Common-Type-1"></span><h3 class="section">24.5 Common Type</h3>
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| 64 | <span id="index-common-type"></span>
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| 65 |
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| 66 | <p>Arithmetic binary operators (except the shift operators) convert their
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| 67 | operands to the <em>common type</em> before operating on them.
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| 68 | Conditional expressions also convert the two possible results to their
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| 69 | common type. Here are the rules for determining the common type.
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| 70 | </p>
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| 71 | <p>If one of the numbers has a floating-point type and the other is an
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| 72 | integer, the common type is that floating-point type. For instance,
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| 73 | </p>
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| 74 | <div class="example">
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| 75 | <pre class="example">5.6 * 2 ⇒ 11.2 /* <span class="roman">a <code>double</code> value</span> */
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| 76 | </pre></div>
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| 77 |
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| 78 | <p>If both are floating point, the type with the larger range is the
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| 79 | common type.
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| 80 | </p>
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| 81 | <p>If both are integers but of different widths, the common type
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| 82 | is the wider of the two.
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| 83 | </p>
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| 84 | <p>If they are integer types of the same width, the common type is
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| 85 | unsigned if either operand is unsigned, and it’s <code>long</code> if either
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| 86 | operand is <code>long</code>. It’s <code>long long</code> if either operand is
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| 87 | <code>long long</code>.
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| 88 | </p>
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| 89 | <p>These rules apply to addition, subtraction, multiplication, division,
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| 90 | remainder, comparisons, and bitwise operations. They also apply to
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| 91 | the two branches of a conditional expression, and to the arithmetic
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| 92 | done in a modifying assignment operation.
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| 93 | </p>
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| 94 |
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| 95 |
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| 96 |
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| 97 | </body>
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| 98 | </html>
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