1<html lang="en"> 2<head> 3<title>Initializers - Using the GNU Compiler Collection (GCC)</title> 4<meta http-equiv="Content-Type" content="text/html"> 5<meta name="description" content="Using the GNU Compiler Collection (GCC)"> 6<meta name="generator" content="makeinfo 4.13"> 7<link title="Top" rel="start" href="index.html#Top"> 8<link rel="up" href="C-Extensions.html#C-Extensions" title="C Extensions"> 9<link rel="prev" href="Pointer-Arith.html#Pointer-Arith" title="Pointer Arith"> 10<link rel="next" href="Compound-Literals.html#Compound-Literals" title="Compound Literals"> 11<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> 12<!-- 13Copyright (C) 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 141998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 152010 Free Software Foundation, Inc. 16 17Permission is granted to copy, distribute and/or modify this document 18under the terms of the GNU Free Documentation License, Version 1.3 or 19any later version published by the Free Software Foundation; with the 20Invariant Sections being ``Funding Free Software'', the Front-Cover 21Texts being (a) (see below), and with the Back-Cover Texts being (b) 22(see below). A copy of the license is included in the section entitled 23``GNU Free Documentation License''. 24 25(a) The FSF's Front-Cover Text is: 26 27 A GNU Manual 28 29(b) The FSF's Back-Cover Text is: 30 31 You have freedom to copy and modify this GNU Manual, like GNU 32 software. Copies published by the Free Software Foundation raise 33 funds for GNU development.--> 34<meta http-equiv="Content-Style-Type" content="text/css"> 35<style type="text/css"><!-- 36 pre.display { font-family:inherit } 37 pre.format { font-family:inherit } 38 pre.smalldisplay { font-family:inherit; font-size:smaller } 39 pre.smallformat { font-family:inherit; font-size:smaller } 40 pre.smallexample { font-size:smaller } 41 pre.smalllisp { font-size:smaller } 42 span.sc { font-variant:small-caps } 43 span.roman { font-family:serif; font-weight:normal; } 44 span.sansserif { font-family:sans-serif; font-weight:normal; } 45--></style> 46<link rel="stylesheet" type="text/css" href="../cs.css"> 47</head> 48<body> 49<div class="node"> 50<a name="Initializers"></a> 51<p> 52Next: <a rel="next" accesskey="n" href="Compound-Literals.html#Compound-Literals">Compound Literals</a>, 53Previous: <a rel="previous" accesskey="p" href="Pointer-Arith.html#Pointer-Arith">Pointer Arith</a>, 54Up: <a rel="up" accesskey="u" href="C-Extensions.html#C-Extensions">C Extensions</a> 55<hr> 56</div> 57 58<h3 class="section">6.24 Non-Constant Initializers</h3> 59 60<p><a name="index-initializers_002c-non_002dconstant-2372"></a><a name="index-non_002dconstant-initializers-2373"></a> 61As in standard C++ and ISO C99, the elements of an aggregate initializer for an 62automatic variable are not required to be constant expressions in GNU C. 63Here is an example of an initializer with run-time varying elements: 64 65<pre class="smallexample"> foo (float f, float g) 66 { 67 float beat_freqs[2] = { f-g, f+g }; 68 /* <span class="roman">...</span> */ 69 } 70</pre> 71 </body></html> 72 73