1<html lang="en"> 2<head> 3<title>Mixed Declarations - 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="Case-Ranges.html#Case-Ranges" title="Case Ranges"> 10<link rel="next" href="Function-Attributes.html#Function-Attributes" title="Function Attributes"> 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="Mixed-Declarations"></a> 51<p> 52Next: <a rel="next" accesskey="n" href="Function-Attributes.html#Function-Attributes">Function Attributes</a>, 53Previous: <a rel="previous" accesskey="p" href="Case-Ranges.html#Case-Ranges">Case Ranges</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">6.29 Mixed Declarations and Code</h3> 59 60<p><a name="index-mixed-declarations-and-code-2389"></a><a name="index-declarations_002c-mixed-with-code-2390"></a><a name="index-code_002c-mixed-with-declarations-2391"></a> 61ISO C99 and ISO C++ allow declarations and code to be freely mixed 62within compound statements. As an extension, GCC also allows this in 63C90 mode. For example, you could do: 64 65<pre class="smallexample"> int i; 66 /* <span class="roman">...</span> */ 67 i++; 68 int j = i + 2; 69</pre> 70 <p>Each identifier is visible from where it is declared until the end of 71the enclosing block. 72 73 </body></html> 74 75