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diff --git a/share/doc/gcc/Messaging-with-the-GNU-Objective_002dC-runtime.html b/share/doc/gcc/Messaging-with-the-GNU-Objective_002dC-runtime.html new file mode 100644 index 0000000..f02af29 --- /dev/null +++ b/share/doc/gcc/Messaging-with-the-GNU-Objective_002dC-runtime.html @@ -0,0 +1,115 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- This file documents the use of the GNU compilers. + +Copyright (C) 1988-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Funding Free Software", the Front-Cover +Texts being (a) (see below), and with the Back-Cover Texts being (b) +(see below). A copy of the license is included in the section entitled +"GNU Free Documentation License". + +(a) The FSF's Front-Cover Text is: + +A GNU Manual + +(b) The FSF's Back-Cover Text is: + +You have freedom to copy and modify this GNU Manual, like GNU + software. Copies published by the Free Software Foundation raise + funds for GNU development. --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>Using the GNU Compiler Collection (GCC): Messaging with the GNU Objective-C runtime</title> + +<meta name="description" content="Using the GNU Compiler Collection (GCC): Messaging with the GNU Objective-C runtime"> +<meta name="keywords" content="Using the GNU Compiler Collection (GCC): Messaging with the GNU Objective-C runtime"> +<meta name="resource-type" content="document"> +<meta name="distribution" content="global"> +<meta name="Generator" content="makeinfo"> +<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> +<link href="index.html#Top" rel="start" title="Top"> +<link href="Indices.html#Indices" rel="index" title="Indices"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="Objective_002dC.html#Objective_002dC" rel="up" title="Objective-C"> +<link href="Dynamically-registering-methods.html#Dynamically-registering-methods" rel="next" title="Dynamically registering methods"> +<link href="Fast-enumeration-protocol.html#Fast-enumeration-protocol" rel="previous" title="Fast enumeration protocol"> +<style type="text/css"> +<!-- +a.summary-letter {text-decoration: none} +blockquote.smallquotation {font-size: smaller} +div.display {margin-left: 3.2em} +div.example {margin-left: 3.2em} +div.indentedblock {margin-left: 3.2em} +div.lisp {margin-left: 3.2em} +div.smalldisplay {margin-left: 3.2em} +div.smallexample {margin-left: 3.2em} +div.smallindentedblock {margin-left: 3.2em; font-size: smaller} +div.smalllisp {margin-left: 3.2em} +kbd {font-style:oblique} +pre.display {font-family: inherit} +pre.format {font-family: inherit} +pre.menu-comment {font-family: serif} +pre.menu-preformatted {font-family: serif} +pre.smalldisplay {font-family: inherit; font-size: smaller} +pre.smallexample {font-size: smaller} +pre.smallformat {font-family: inherit; font-size: smaller} +pre.smalllisp {font-size: smaller} +span.nocodebreak {white-space:nowrap} +span.nolinebreak {white-space:nowrap} +span.roman {font-family:serif; font-weight:normal} +span.sansserif {font-family:sans-serif; font-weight:normal} +ul.no-bullet {list-style: none} +--> +</style> + + +</head> + +<body lang="en_US" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> +<a name="Messaging-with-the-GNU-Objective_002dC-runtime"></a> +<div class="header"> +<p> +Previous: <a href="Fast-enumeration.html#Fast-enumeration" accesskey="p" rel="previous">Fast enumeration</a>, Up: <a href="Objective_002dC.html#Objective_002dC" accesskey="u" rel="up">Objective-C</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Indices.html#Indices" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="Messaging-with-the-GNU-Objective_002dC-Runtime"></a> +<h3 class="section">8.10 Messaging with the GNU Objective-C Runtime</h3> + +<p>This section is specific for the GNU Objective-C runtime. If you are +using a different runtime, you can skip it. +</p> +<p>The implementation of messaging in the GNU Objective-C runtime is +designed to be portable, and so is based on standard C. +</p> +<p>Sending a message in the GNU Objective-C runtime is composed of two +separate steps. First, there is a call to the lookup function, +<code>objc_msg_lookup ()</code> (or, in the case of messages to super, +<code>objc_msg_lookup_super ()</code>). This runtime function takes as +argument the receiver and the selector of the method to be called; it +returns the <code>IMP</code>, that is a pointer to the function implementing +the method. The second step of method invocation consists of casting +this pointer function to the appropriate function pointer type, and +calling the function pointed to it with the right arguments. +</p> +<p>For example, when the compiler encounters a method invocation such as +<code>[object init]</code>, it compiles it into a call to +<code>objc_msg_lookup (object, @selector(init))</code> followed by a cast +of the returned value to the appropriate function pointer type, and +then it calls it. +</p> +<table class="menu" border="0" cellspacing="0"> +<tr><td align="left" valign="top">• <a href="Dynamically-registering-methods.html#Dynamically-registering-methods" accesskey="1">Dynamically registering methods</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="Forwarding-hook.html#Forwarding-hook" accesskey="2">Forwarding hook</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +</table> + + + + +</body> +</html> |