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<title>Subscripting - Using the GNU Compiler Collection (GCC)</title>
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<a name="Subscripting"></a>
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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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<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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