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diff --git a/share/doc/gccint/Classes.html b/share/doc/gccint/Classes.html new file mode 100644 index 0000000..7987927 --- /dev/null +++ b/share/doc/gccint/Classes.html @@ -0,0 +1,239 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- 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>GNU Compiler Collection (GCC) Internals: Classes</title> + +<meta name="description" content="GNU Compiler Collection (GCC) Internals: Classes"> +<meta name="keywords" content="GNU Compiler Collection (GCC) Internals: Classes"> +<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="Option-Index.html#Option-Index" rel="index" title="Option Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="C-and-C_002b_002b-Trees.html#C-and-C_002b_002b-Trees" rel="up" title="C and C++ Trees"> +<link href="Functions-for-C_002b_002b.html#Functions-for-C_002b_002b" rel="next" title="Functions for C++"> +<link href="Namespaces.html#Namespaces" rel="previous" title="Namespaces"> +<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" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> +<a name="Classes"></a> +<div class="header"> +<p> +Next: <a href="Functions-for-C_002b_002b.html#Functions-for-C_002b_002b" accesskey="n" rel="next">Functions for C++</a>, Previous: <a href="Namespaces.html#Namespaces" accesskey="p" rel="previous">Namespaces</a>, Up: <a href="C-and-C_002b_002b-Trees.html#C-and-C_002b_002b-Trees" accesskey="u" rel="up">C and C++ Trees</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="Classes-1"></a> +<h4 class="subsection">11.10.3 Classes</h4> +<a name="index-class_002c-scope"></a> +<a name="index-RECORD_005fTYPE-1"></a> +<a name="index-UNION_005fTYPE-1"></a> +<a name="index-CLASSTYPE_005fDECLARED_005fCLASS"></a> +<a name="index-TYPE_005fBINFO"></a> +<a name="index-BINFO_005fTYPE"></a> +<a name="index-TYPE_005fFIELDS-2"></a> +<a name="index-TYPE_005fVFIELD"></a> + +<p>Besides namespaces, the other high-level scoping construct in C++ is the +class. (Throughout this manual the term <em>class</em> is used to mean the +types referred to in the ANSI/ISO C++ Standard as classes; these include +types defined with the <code>class</code>, <code>struct</code>, and <code>union</code> +keywords.) +</p> +<p>A class type is represented by either a <code>RECORD_TYPE</code> or a +<code>UNION_TYPE</code>. A class declared with the <code>union</code> tag is +represented by a <code>UNION_TYPE</code>, while classes declared with either +the <code>struct</code> or the <code>class</code> tag are represented by +<code>RECORD_TYPE</code>s. You can use the <code>CLASSTYPE_DECLARED_CLASS</code> +macro to discern whether or not a particular type is a <code>class</code> as +opposed to a <code>struct</code>. This macro will be true only for classes +declared with the <code>class</code> tag. +</p> +<p>Almost all members are available on the <code>TYPE_FIELDS</code> +list. Given one member, the next can be found by following the +<code>TREE_CHAIN</code>. You should not depend in any way on the order in +which fields appear on this list. All nodes on this list will be +‘<samp>DECL</samp>’ nodes. A <code>FIELD_DECL</code> is used to represent a non-static +data member, a <code>VAR_DECL</code> is used to represent a static data +member, and a <code>TYPE_DECL</code> is used to represent a type. Note that +the <code>CONST_DECL</code> for an enumeration constant will appear on this +list, if the enumeration type was declared in the class. (Of course, +the <code>TYPE_DECL</code> for the enumeration type will appear here as well.) +There are no entries for base classes on this list. In particular, +there is no <code>FIELD_DECL</code> for the “base-class portion” of an +object. If a function member is overloaded, each of the overloaded +functions appears; no <code>OVERLOAD</code> nodes appear on the <code>TYPE_FIELDS</code> +list. Implicitly declared functions (including default constructors, +copy constructors, assignment operators, and destructors) will appear on +this list as well. +</p> +<p>The <code>TYPE_VFIELD</code> is a compiler-generated field used to point to +virtual function tables. It may or may not appear on the +<code>TYPE_FIELDS</code> list. However, back ends should handle the +<code>TYPE_VFIELD</code> just like all the entries on the <code>TYPE_FIELDS</code> +list. +</p> +<p>Every class has an associated <em>binfo</em>, which can be obtained with +<code>TYPE_BINFO</code>. Binfos are used to represent base-classes. The +binfo given by <code>TYPE_BINFO</code> is the degenerate case, whereby every +class is considered to be its own base-class. The base binfos for a +particular binfo are held in a vector, whose length is obtained with +<code>BINFO_N_BASE_BINFOS</code>. The base binfos themselves are obtained +with <code>BINFO_BASE_BINFO</code> and <code>BINFO_BASE_ITERATE</code>. To add a +new binfo, use <code>BINFO_BASE_APPEND</code>. The vector of base binfos can +be obtained with <code>BINFO_BASE_BINFOS</code>, but normally you do not need +to use that. The class type associated with a binfo is given by +<code>BINFO_TYPE</code>. It is not always the case that <code>BINFO_TYPE +(TYPE_BINFO (x))</code>, because of typedefs and qualified types. Neither is +it the case that <code>TYPE_BINFO (BINFO_TYPE (y))</code> is the same binfo as +<code>y</code>. The reason is that if <code>y</code> is a binfo representing a +base-class <code>B</code> of a derived class <code>D</code>, then <code>BINFO_TYPE +(y)</code> will be <code>B</code>, and <code>TYPE_BINFO (BINFO_TYPE (y))</code> will be +<code>B</code> as its own base-class, rather than as a base-class of <code>D</code>. +</p> +<p>The access to a base type can be found with <code>BINFO_BASE_ACCESS</code>. +This will produce <code>access_public_node</code>, <code>access_private_node</code> +or <code>access_protected_node</code>. If bases are always public, +<code>BINFO_BASE_ACCESSES</code> may be <code>NULL</code>. +</p> +<p><code>BINFO_VIRTUAL_P</code> is used to specify whether the binfo is inherited +virtually or not. The other flags, <code>BINFO_FLAG_0</code> to +<code>BINFO_FLAG_6</code>, can be used for language specific use. +</p> +<p>The following macros can be used on a tree node representing a class-type. +</p> +<dl compact="compact"> +<dt><code>LOCAL_CLASS_P</code> +<a name="index-LOCAL_005fCLASS_005fP"></a> +</dt> +<dd><p>This predicate holds if the class is local class <em>i.e.</em> declared +inside a function body. +</p> +</dd> +<dt><code>TYPE_POLYMORPHIC_P</code> +<a name="index-TYPE_005fPOLYMORPHIC_005fP"></a> +</dt> +<dd><p>This predicate holds if the class has at least one virtual function +(declared or inherited). +</p> +</dd> +<dt><code>TYPE_HAS_DEFAULT_CONSTRUCTOR</code> +<a name="index-TYPE_005fHAS_005fDEFAULT_005fCONSTRUCTOR"></a> +</dt> +<dd><p>This predicate holds whenever its argument represents a class-type with +default constructor. +</p> +</dd> +<dt><code>CLASSTYPE_HAS_MUTABLE</code> +<a name="index-CLASSTYPE_005fHAS_005fMUTABLE"></a> +</dt> +<dt><code>TYPE_HAS_MUTABLE_P</code> +<a name="index-TYPE_005fHAS_005fMUTABLE_005fP"></a> +</dt> +<dd><p>These predicates hold for a class-type having a mutable data member. +</p> +</dd> +<dt><code>CLASSTYPE_NON_POD_P</code> +<a name="index-CLASSTYPE_005fNON_005fPOD_005fP"></a> +</dt> +<dd><p>This predicate holds only for class-types that are not PODs. +</p> +</dd> +<dt><code>TYPE_HAS_NEW_OPERATOR</code> +<a name="index-TYPE_005fHAS_005fNEW_005fOPERATOR"></a> +</dt> +<dd><p>This predicate holds for a class-type that defines +<code>operator new</code>. +</p> +</dd> +<dt><code>TYPE_HAS_ARRAY_NEW_OPERATOR</code> +<a name="index-TYPE_005fHAS_005fARRAY_005fNEW_005fOPERATOR"></a> +</dt> +<dd><p>This predicate holds for a class-type for which +<code>operator new[]</code> is defined. +</p> +</dd> +<dt><code>TYPE_OVERLOADS_CALL_EXPR</code> +<a name="index-TYPE_005fOVERLOADS_005fCALL_005fEXPR"></a> +</dt> +<dd><p>This predicate holds for class-type for which the function call +<code>operator()</code> is overloaded. +</p> +</dd> +<dt><code>TYPE_OVERLOADS_ARRAY_REF</code> +<a name="index-TYPE_005fOVERLOADS_005fARRAY_005fREF"></a> +</dt> +<dd><p>This predicate holds for a class-type that overloads +<code>operator[]</code> +</p> +</dd> +<dt><code>TYPE_OVERLOADS_ARROW</code> +<a name="index-TYPE_005fOVERLOADS_005fARROW"></a> +</dt> +<dd><p>This predicate holds for a class-type for which <code>operator-></code> is +overloaded. +</p> +</dd> +</dl> + +<hr> +<div class="header"> +<p> +Next: <a href="Functions-for-C_002b_002b.html#Functions-for-C_002b_002b" accesskey="n" rel="next">Functions for C++</a>, Previous: <a href="Namespaces.html#Namespaces" accesskey="p" rel="previous">Namespaces</a>, Up: <a href="C-and-C_002b_002b-Trees.html#C-and-C_002b_002b-Trees" accesskey="u" rel="up">C and C++ Trees</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |