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| author | alk3pInjection <webmaster@raspii.tech> | 2024-02-04 16:16:35 +0800 |
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| committer | alk3pInjection <webmaster@raspii.tech> | 2024-02-04 16:16:35 +0800 |
| commit | abdaadbcae30fe0c9a66c7516798279fdfd97750 (patch) | |
| tree | 00a54a6e25601e43876d03c1a4a12a749d4a914c /share/doc/gcc/Conditionals.html | |
https://developer.arm.com/downloads/-/arm-gnu-toolchain-downloads
Change-Id: I7303388733328cd98ab9aa3c30236db67f2e9e9c
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| -rw-r--r-- | share/doc/gcc/Conditionals.html | 119 |
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diff --git a/share/doc/gcc/Conditionals.html b/share/doc/gcc/Conditionals.html new file mode 100644 index 0000000..d7e277c --- /dev/null +++ b/share/doc/gcc/Conditionals.html @@ -0,0 +1,119 @@ +<!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): Conditionals</title> + +<meta name="description" content="Using the GNU Compiler Collection (GCC): Conditionals"> +<meta name="keywords" content="Using the GNU Compiler Collection (GCC): Conditionals"> +<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="_005f_005fint128.html#g_t_005f_005fint128" rel="next" title="__int128"> +<link href="Typeof.html#Typeof" rel="previous" title="Typeof"> +<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="Conditionals"></a> +<div class="header"> +<p> +Next: <a href="_005f_005fint128.html#g_t_005f_005fint128" accesskey="n" rel="next">__int128</a>, Previous: <a href="Typeof.html#Typeof" accesskey="p" rel="previous">Typeof</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="Conditionals-with-Omitted-Operands"></a> +<h3 class="section">6.8 Conditionals with Omitted Operands</h3> +<a name="index-conditional-expressions_002c-extensions"></a> +<a name="index-omitted-middle_002doperands"></a> +<a name="index-middle_002doperands_002c-omitted"></a> +<a name="index-extensions_002c-_003f_003a"></a> +<a name="index-_003f_003a-extensions"></a> + +<p>The middle operand in a conditional expression may be omitted. Then +if the first operand is nonzero, its value is the value of the conditional +expression. +</p> +<p>Therefore, the expression +</p> +<div class="smallexample"> +<pre class="smallexample">x ? : y +</pre></div> + +<p>has the value of <code>x</code> if that is nonzero; otherwise, the value of +<code>y</code>. +</p> +<p>This example is perfectly equivalent to +</p> +<div class="smallexample"> +<pre class="smallexample">x ? x : y +</pre></div> + +<a name="index-side-effect-in-_003f_003a"></a> +<a name="index-_003f_003a-side-effect"></a> +<p>In this simple case, the ability to omit the middle operand is not +especially useful. When it becomes useful is when the first operand does, +or may (if it is a macro argument), contain a side effect. Then repeating +the operand in the middle would perform the side effect twice. Omitting +the middle operand uses the value already computed without the undesirable +effects of recomputing it. +</p> + + + +</body> +</html> |