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-Extensions.html#C-Extensions" title="C Extensions"> 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) 1988-2013 Free Software Foundation, Inc. 13 14Permission is granted to copy, distribute and/or modify this document 15under the terms of the GNU Free Documentation License, Version 1.3 or 16any later version published by the Free Software Foundation; with the 17Invariant Sections being ``Funding Free Software'', the Front-Cover 18Texts being (a) (see below), and with the Back-Cover Texts being (b) 19(see below). 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If you 61want to write code that checks whether these features are available, you can 62test for the GNU compiler the same way as for C programs: check for a 63predefined macro <code>__GNUC__</code>. You can also use <code>__GNUG__</code> to 64test specifically for GNU C++ (see <a href="../cpp/Common-Predefined-Macros.html#Common-Predefined-Macros">Predefined Macros</a>). 65 66<ul class="menu"> 67<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. 68<li><a accesskey="2" href="Restricted-Pointers.html#Restricted-Pointers">Restricted Pointers</a>: C99 restricted pointers and references. 69<li><a accesskey="3" href="Vague-Linkage.html#Vague-Linkage">Vague Linkage</a>: Where G++ puts inlines, vtables and such. 70<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 71 declarations and definitions. 72<li><a accesskey="5" href="Template-Instantiation.html#Template-Instantiation">Template Instantiation</a>: Methods for ensuring that exactly one copy of 73 each needed template instantiation is emitted. 74<li><a accesskey="6" href="Bound-member-functions.html#Bound-member-functions">Bound member functions</a>: You can extract a function pointer to the 75 method denoted by a ‘<samp><span class="samp">->*</span></samp>’ or ‘<samp><span class="samp">.*</span></samp>’ expression. 76<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. 77<li><a accesskey="8" href="Function-Multiversioning.html#Function-Multiversioning">Function Multiversioning</a>: Declaring multiple function versions. 78<li><a accesskey="9" href="Namespace-Association.html#Namespace-Association">Namespace Association</a>: Strong using-directives for namespace association. 79<li><a href="Type-Traits.html#Type-Traits">Type Traits</a>: Compiler support for type traits 80<li><a href="Java-Exceptions.html#Java-Exceptions">Java Exceptions</a>: Tweaking exception handling to work with Java. 81<li><a href="Deprecated-Features.html#Deprecated-Features">Deprecated Features</a>: Things will disappear from G++. 82<li><a href="Backwards-Compatibility.html#Backwards-Compatibility">Backwards Compatibility</a>: Compatibilities with earlier definitions of C++. 83</ul> 84 85 </body></html> 86 87