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diff --git a/share/doc/gcc/Function-Names.html b/share/doc/gcc/Function-Names.html new file mode 100644 index 0000000..781a261 --- /dev/null +++ b/share/doc/gcc/Function-Names.html @@ -0,0 +1,154 @@ +<!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): Function Names</title> + +<meta name="description" content="Using the GNU Compiler Collection (GCC): Function Names"> +<meta name="keywords" content="Using the GNU Compiler Collection (GCC): Function Names"> +<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="C-Extensions.html#C-Extensions" rel="up" title="C Extensions"> +<link href="Return-Address.html#Return-Address" rel="next" title="Return Address"> +<link href="Incomplete-Enums.html#Incomplete-Enums" rel="previous" title="Incomplete Enums"> +<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="Function-Names"></a> +<div class="header"> +<p> +Next: <a href="Return-Address.html#Return-Address" accesskey="n" rel="next">Return Address</a>, Previous: <a href="Incomplete-Enums.html#Incomplete-Enums" accesskey="p" rel="previous">Incomplete Enums</a>, Up: <a href="C-Extensions.html#C-Extensions" accesskey="u" rel="up">C Extensions</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="Function-Names-as-Strings"></a> +<h3 class="section">6.50 Function Names as Strings</h3> +<a name="index-_005f_005ffunc_005f_005f-identifier"></a> +<a name="index-_005f_005fFUNCTION_005f_005f-identifier"></a> +<a name="index-_005f_005fPRETTY_005fFUNCTION_005f_005f-identifier"></a> + +<p>GCC provides three magic constants that hold the name of the current +function as a string. In C++11 and later modes, all three are treated +as constant expressions and can be used in <code>constexpr</code> constexts. +The first of these constants is <code>__func__</code>, which is part of +the C99 standard: +</p> +<p>The identifier <code>__func__</code> is implicitly declared by the translator +as if, immediately following the opening brace of each function +definition, the declaration +</p> +<div class="smallexample"> +<pre class="smallexample">static const char __func__[] = "function-name"; +</pre></div> + +<p>appeared, where function-name is the name of the lexically-enclosing +function. This name is the unadorned name of the function. As an +extension, at file (or, in C++, namespace scope), <code>__func__</code> +evaluates to the empty string. +</p> +<p><code>__FUNCTION__</code> is another name for <code>__func__</code>, provided for +backward compatibility with old versions of GCC. +</p> +<p>In C, <code>__PRETTY_FUNCTION__</code> is yet another name for +<code>__func__</code>, except that at file scope (or, in C++, namespace scope), +it evaluates to the string <code>"top level"</code>. In addition, in C++, +<code>__PRETTY_FUNCTION__</code> contains the signature of the function as +well as its bare name. For example, this program: +</p> +<div class="smallexample"> +<pre class="smallexample">extern "C" int printf (const char *, ...); + +class a { + public: + void sub (int i) + { + printf ("__FUNCTION__ = %s\n", __FUNCTION__); + printf ("__PRETTY_FUNCTION__ = %s\n", __PRETTY_FUNCTION__); + } +}; + +int +main (void) +{ + a ax; + ax.sub (0); + return 0; +} +</pre></div> + +<p>gives this output: +</p> +<div class="smallexample"> +<pre class="smallexample">__FUNCTION__ = sub +__PRETTY_FUNCTION__ = void a::sub(int) +</pre></div> + +<p>These identifiers are variables, not preprocessor macros, and may not +be used to initialize <code>char</code> arrays or be concatenated with string +literals. +</p> +<hr> +<div class="header"> +<p> +Next: <a href="Return-Address.html#Return-Address" accesskey="n" rel="next">Return Address</a>, Previous: <a href="Incomplete-Enums.html#Incomplete-Enums" accesskey="p" rel="previous">Incomplete Enums</a>, Up: <a href="C-Extensions.html#C-Extensions" accesskey="u" rel="up">C Extensions</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> + + + +</body> +</html> |