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77 lines
3.2 KiB
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77 lines
3.2 KiB
HTML
4 years ago
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<title>Subscripting - Using the GNU Compiler Collection (GCC)</title>
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<meta name="description" content="Using the GNU Compiler Collection (GCC)">
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<link title="Top" rel="start" href="index.html#Top">
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<link rel="up" href="C-Extensions.html#C-Extensions" title="C Extensions">
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<link rel="prev" href="Escaped-Newlines.html#Escaped-Newlines" title="Escaped Newlines">
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<link rel="next" href="Pointer-Arith.html#Pointer-Arith" title="Pointer Arith">
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Copyright (C) 1988-2015 Free Software Foundation, Inc.
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Permission is granted to copy, distribute and/or modify this document
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under the terms of the GNU Free Documentation License, Version 1.3 or
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any later version published by the Free Software Foundation; with the
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Invariant Sections being ``Funding Free Software'', the Front-Cover
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(see below). A copy of the license is included in the section entitled
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``GNU Free Documentation License''.
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(a) The FSF's Front-Cover Text is:
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A GNU Manual
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(b) The FSF's Back-Cover Text is:
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You have freedom to copy and modify this GNU Manual, like GNU
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</head>
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<body>
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<div class="node">
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<a name="Subscripting"></a>
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<p>
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Next: <a rel="next" accesskey="n" href="Pointer-Arith.html#Pointer-Arith">Pointer Arith</a>,
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Previous: <a rel="previous" accesskey="p" href="Escaped-Newlines.html#Escaped-Newlines">Escaped Newlines</a>,
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Up: <a rel="up" accesskey="u" href="C-Extensions.html#C-Extensions">C Extensions</a>
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<hr>
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</div>
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<h3 class="section">6.22 Non-Lvalue Arrays May Have Subscripts</h3>
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<p><a name="index-subscripting-3004"></a><a name="index-arrays_002c-non_002dlvalue-3005"></a>
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<a name="index-subscripting-and-function-values-3006"></a>In ISO C99, arrays that are not lvalues still decay to pointers, and
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may be subscripted, although they may not be modified or used after
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the next sequence point and the unary ‘<samp><span class="samp">&</span></samp>’ operator may not be
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applied to them. As an extension, GNU C allows such arrays to be
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subscripted in C90 mode, though otherwise they do not decay to
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pointers outside C99 mode. For example,
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this is valid in GNU C though not valid in C90:
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<pre class="smallexample"> struct foo {int a[4];};
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struct foo f();
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bar (int index)
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{
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return f().a[index];
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}
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</pre>
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</body></html>
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