<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <html> <head> <meta http-equiv="Content-Type" content="text/html;charset=iso-8859-1"> <title>avr-libc: <alloca.h>: Allocate space in the stack</title> <link href="dox.css" rel="stylesheet" type="text/css"> </head> <body> <center> <table width="80%"> <tr> <td align="left"><a href="http://www.nongnu.org/avr-libc/">AVR Libc Home Page</a></td> <td align="center" colspan=4><img src="avrs.png" alt="AVRs" align="middle" border="0"></td> <td align="right"><a href="https://savannah.nongnu.org/projects/avr-libc/">AVR Libc Development Pages</a></td> </tr> <tr> <td align="center" width="13%"><a href="index.html">Main Page</a></td> <td align="center" width="13%"><a href="pages.html">User Manual</a></td> <td align="center" width="13%"><a href="modules.html">Library Reference</a></td> <td align="center" width="13%"><a href="FAQ.html">FAQ</a></td> <td align="center" width="13%"><a href="globals.html">Alphabetical Index</a></td> <td align="center" width="13%"><a href="group__demos.html">Example Projects</a></td> </tr> </table> </center> <hr width="80%"> <!-- Generated by Doxygen 1.5.6 --> <div class="contents"> <h1><alloca.h>: Allocate space in the stack</h1><hr><a name="_details"></a><h2>Detailed Description</h2> <p> <table border="0" cellpadding="0" cellspacing="0"> <tr><td></td></tr> <tr><td colspan="2"><br><h2>Functions</h2></td></tr> <tr><td class="memItemLeft" nowrap align="right" valign="top">void * </td><td class="memItemRight" valign="bottom"><a class="el" href="group__alloca.html#gbdd78c9d072e9d390bed0e8b79087a85">alloca</a> (size_t __size)</td></tr> </table> <hr><h2>Function Documentation</h2> <a class="anchor" name="gbdd78c9d072e9d390bed0e8b79087a85"></a><!-- doxytag: member="alloca.h::alloca" ref="gbdd78c9d072e9d390bed0e8b79087a85" args="(size_t __size)" --> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">void* alloca </td> <td>(</td> <td class="paramtype">size_t </td> <td class="paramname"> <em>__size</em> </td> <td> ) </td> <td></td> </tr> </table> </div> <div class="memdoc"> <p> Allocate <em>__size</em> bytes of space in the stack frame of the caller. <p> This temporary space is automatically freed when the function that called <a class="el" href="group__alloca.html#gbdd78c9d072e9d390bed0e8b79087a85" title="Allocate __size bytes of space in the stack frame of the caller.">alloca()</a> returns to its caller. Avr-libc defines the <a class="el" href="group__alloca.html#gbdd78c9d072e9d390bed0e8b79087a85" title="Allocate __size bytes of space in the stack frame of the caller.">alloca()</a> as a macro, which is translated into the inlined <code>__builtin_alloca()</code> function. The fact that the code is inlined, means that it is impossible to take the address of this function, or to change its behaviour by linking with a different library.<p> <dl class="return" compact><dt><b>Returns:</b></dt><dd><a class="el" href="group__alloca.html#gbdd78c9d072e9d390bed0e8b79087a85" title="Allocate __size bytes of space in the stack frame of the caller.">alloca()</a> returns a pointer to the beginning of the allocated space. If the allocation causes stack overflow, program behaviour is undefined.</dd></dl> <dl class="warning" compact><dt><b>Warning:</b></dt><dd>Avoid use <a class="el" href="group__alloca.html#gbdd78c9d072e9d390bed0e8b79087a85" title="Allocate __size bytes of space in the stack frame of the caller.">alloca()</a> inside the list of arguments of a function call. </dd></dl> </div> </div><p> </div> <hr width="80%"> <p><center>Automatically generated by Doxygen 1.5.6 on 4 Dec 2008.</center></p> </body> </html>