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diff --git a/share/doc/cpp/Diagnostics.html b/share/doc/cpp/Diagnostics.html new file mode 100644 index 0000000..6a4d09b --- /dev/null +++ b/share/doc/cpp/Diagnostics.html @@ -0,0 +1,128 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1987-2023 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. A copy of +the license is included in the +section entitled "GNU Free Documentation License". + +This manual contains no Invariant Sections. The Front-Cover Texts are +(a) (see below), and the Back-Cover Texts are (b) (see below). + +(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>The C Preprocessor: Diagnostics</title> + +<meta name="description" content="The C Preprocessor: Diagnostics"> +<meta name="keywords" content="The C Preprocessor: Diagnostics"> +<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="Index-of-Directives.html#Index-of-Directives" rel="index" title="Index of Directives"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="index.html#Top" rel="up" title="Top"> +<link href="Line-Control.html#Line-Control" rel="next" title="Line Control"> +<link href="Deleted-Code.html#Deleted-Code" rel="previous" title="Deleted Code"> +<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="Diagnostics"></a> +<div class="header"> +<p> +Next: <a href="Line-Control.html#Line-Control" accesskey="n" rel="next">Line Control</a>, Previous: <a href="Conditionals.html#Conditionals" accesskey="p" rel="previous">Conditionals</a>, Up: <a href="index.html#Top" accesskey="u" rel="up">Top</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Index-of-Directives.html#Index-of-Directives" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="Diagnostics-1"></a> +<h2 class="chapter">5 Diagnostics</h2> +<a name="index-diagnostic"></a> +<a name="index-reporting-errors"></a> +<a name="index-reporting-warnings"></a> + +<a name="index-_0023error"></a> +<p>The directive ‘<samp>#error</samp>’ causes the preprocessor to report a fatal +error. The tokens forming the rest of the line following ‘<samp>#error</samp>’ +are used as the error message. +</p> +<p>You would use ‘<samp>#error</samp>’ inside of a conditional that detects a +combination of parameters which you know the program does not properly +support. For example, if you know that the program will not run +properly on a VAX, you might write +</p> +<div class="smallexample"> +<pre class="smallexample">#ifdef __vax__ +#error "Won't work on VAXen. See comments at get_last_object." +#endif +</pre></div> + +<p>If you have several configuration parameters that must be set up by +the installation in a consistent way, you can use conditionals to detect +an inconsistency and report it with ‘<samp>#error</samp>’. For example, +</p> +<div class="smallexample"> +<pre class="smallexample">#if !defined(FOO) && defined(BAR) +#error "BAR requires FOO." +#endif +</pre></div> + +<a name="index-_0023warning"></a> +<p>The directive ‘<samp>#warning</samp>’ is like ‘<samp>#error</samp>’, but causes the +preprocessor to issue a warning and continue preprocessing. The tokens +following ‘<samp>#warning</samp>’ are used as the warning message. +</p> +<p>You might use ‘<samp>#warning</samp>’ in obsolete header files, with a message +directing the user to the header file which should be used instead. +</p> +<p>Neither ‘<samp>#error</samp>’ nor ‘<samp>#warning</samp>’ macro-expands its argument. +Internal whitespace sequences are each replaced with a single space. +The line must consist of complete tokens. It is wisest to make the +argument of these directives be a single string constant; this avoids +problems with apostrophes and the like. +</p> + + + +</body> +</html> |