1<html lang="en"> 2<head> 3<title>Push/Pop Macro Pragmas - 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="Pragmas.html#Pragmas" title="Pragmas"> 9<link rel="prev" href="Visibility-Pragmas.html#Visibility-Pragmas" title="Visibility Pragmas"> 10<link rel="next" href="Function-Specific-Option-Pragmas.html#Function-Specific-Option-Pragmas" title="Function Specific Option Pragmas"> 11<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> 12<!-- 13Copyright (C) 1988-2013 Free Software Foundation, Inc. 14 15Permission is granted to copy, distribute and/or modify this document 16under the terms of the GNU Free Documentation License, Version 1.3 or 17any later version published by the Free Software Foundation; with the 18Invariant Sections being ``Funding Free Software'', the Front-Cover 19Texts being (a) (see below), and with the Back-Cover Texts being (b) 20(see below). A copy of the license is included in the section entitled 21``GNU Free Documentation License''. 22 23(a) The FSF's Front-Cover Text is: 24 25 A GNU Manual 26 27(b) The FSF's Back-Cover Text is: 28 29 You have freedom to copy and modify this GNU Manual, like GNU 30 software. Copies published by the Free Software Foundation raise 31 funds for GNU development.--> 32<meta http-equiv="Content-Style-Type" content="text/css"> 33<style type="text/css"><!-- 34 pre.display { font-family:inherit } 35 pre.format { font-family:inherit } 36 pre.smalldisplay { font-family:inherit; font-size:smaller } 37 pre.smallformat { font-family:inherit; font-size:smaller } 38 pre.smallexample { font-size:smaller } 39 pre.smalllisp { font-size:smaller } 40 span.sc { font-variant:small-caps } 41 span.roman { font-family:serif; font-weight:normal; } 42 span.sansserif { font-family:sans-serif; font-weight:normal; } 43--></style> 44<link rel="stylesheet" type="text/css" href="../cs.css"> 45</head> 46<body> 47<div class="node"> 48<a name="Push%2fPop-Macro-Pragmas"></a> 49<a name="Push_002fPop-Macro-Pragmas"></a> 50<p> 51Next: <a rel="next" accesskey="n" href="Function-Specific-Option-Pragmas.html#Function-Specific-Option-Pragmas">Function Specific Option Pragmas</a>, 52Previous: <a rel="previous" accesskey="p" href="Visibility-Pragmas.html#Visibility-Pragmas">Visibility Pragmas</a>, 53Up: <a rel="up" accesskey="u" href="Pragmas.html#Pragmas">Pragmas</a> 54<hr> 55</div> 56 57<h4 class="subsection">6.58.12 Push/Pop Macro Pragmas</h4> 58 59<p>For compatibility with Microsoft Windows compilers, GCC supports 60‘<samp><span class="samp">#pragma push_macro(</span><var>"macro_name"</var><span class="samp">)</span></samp>’ 61and ‘<samp><span class="samp">#pragma pop_macro(</span><var>"macro_name"</var><span class="samp">)</span></samp>’. 62 63 <dl> 64<dt><code>#pragma push_macro(</code><var>"macro_name"</var><code>)</code><dd><a name="index-pragma_002c-push_005fmacro-3484"></a>This pragma saves the value of the macro named as <var>macro_name</var> to 65the top of the stack for this macro. 66 67 <br><dt><code>#pragma pop_macro(</code><var>"macro_name"</var><code>)</code><dd><a name="index-pragma_002c-pop_005fmacro-3485"></a>This pragma sets the value of the macro named as <var>macro_name</var> to 68the value on top of the stack for this macro. If the stack for 69<var>macro_name</var> is empty, the value of the macro remains unchanged. 70</dl> 71 72 <p>For example: 73 74<pre class="smallexample"> #define X 1 75 #pragma push_macro("X") 76 #undef X 77 #define X -1 78 #pragma pop_macro("X") 79 int x [X]; 80</pre> 81 <p class="noindent">In this example, the definition of X as 1 is saved by <code>#pragma 82push_macro</code> and restored by <code>#pragma pop_macro</code>. 83 84 </body></html> 85 86