1<html lang="en"> 2<head> 3<title>C++ Extensions - 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="prev" href="C_002b_002b-Implementation.html#C_002b_002b-Implementation" title="C++ Implementation"> 9<link rel="next" href="Objective_002dC.html#Objective_002dC" title="Objective-C"> 10<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> 11<!-- 12Copyright (C) 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 131998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 142010 Free Software Foundation, Inc. 15 16Permission is granted to copy, distribute and/or modify this document 17under the terms of the GNU Free Documentation License, Version 1.3 or 18any later version published by the Free Software Foundation; with the 19Invariant Sections being ``Funding Free Software'', the Front-Cover 20Texts being (a) (see below), and with the Back-Cover Texts being (b) 21(see below). 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If you 63want to write code that checks whether these features are available, you can 64test for the GNU compiler the same way as for C programs: check for a 65predefined macro <code>__GNUC__</code>. You can also use <code>__GNUG__</code> to 66test specifically for GNU C++ (see <a href="../cpp/Common-Predefined-Macros.html#Common-Predefined-Macros">Predefined Macros</a>). 67 68<ul class="menu"> 69<li><a accesskey="1" href="C_002b_002b-Volatiles.html#C_002b_002b-Volatiles">C++ Volatiles</a>: What constitutes an access to a volatile object. 70<li><a accesskey="2" href="Restricted-Pointers.html#Restricted-Pointers">Restricted Pointers</a>: C99 restricted pointers and references. 71<li><a accesskey="3" href="Vague-Linkage.html#Vague-Linkage">Vague Linkage</a>: Where G++ puts inlines, vtables and such. 72<li><a accesskey="4" href="C_002b_002b-Interface.html#C_002b_002b-Interface">C++ Interface</a>: You can use a single C++ header file for both 73 declarations and definitions. 74<li><a accesskey="5" href="Template-Instantiation.html#Template-Instantiation">Template Instantiation</a>: Methods for ensuring that exactly one copy of 75 each needed template instantiation is emitted. 76<li><a accesskey="6" href="Bound-member-functions.html#Bound-member-functions">Bound member functions</a>: You can extract a function pointer to the 77 method denoted by a ‘<samp><span class="samp">->*</span></samp>’ or ‘<samp><span class="samp">.*</span></samp>’ expression. 78<li><a accesskey="7" href="C_002b_002b-Attributes.html#C_002b_002b-Attributes">C++ Attributes</a>: Variable, function, and type attributes for C++ only. 79<li><a accesskey="8" href="Namespace-Association.html#Namespace-Association">Namespace Association</a>: Strong using-directives for namespace association. 80<li><a accesskey="9" href="Type-Traits.html#Type-Traits">Type Traits</a>: Compiler support for type traits 81<li><a href="Java-Exceptions.html#Java-Exceptions">Java Exceptions</a>: Tweaking exception handling to work with Java. 82<li><a href="Deprecated-Features.html#Deprecated-Features">Deprecated Features</a>: Things will disappear from g++. 83<li><a href="Backwards-Compatibility.html#Backwards-Compatibility">Backwards Compatibility</a>: Compatibilities with earlier definitions of C++. 84</ul> 85 86 </body></html> 87 88