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diff --git a/share/doc/cpp/Implementation-limits.html b/share/doc/cpp/Implementation-limits.html new file mode 100644 index 0000000..80ba0b4 --- /dev/null +++ b/share/doc/cpp/Implementation-limits.html @@ -0,0 +1,152 @@ +<!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: Implementation limits</title> + +<meta name="description" content="The C Preprocessor: Implementation limits"> +<meta name="keywords" content="The C Preprocessor: Implementation limits"> +<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="Implementation-Details.html#Implementation-Details" rel="up" title="Implementation Details"> +<link href="Obsolete-Features.html#Obsolete-Features" rel="next" title="Obsolete Features"> +<link href="Implementation_002ddefined-behavior.html#Implementation_002ddefined-behavior" rel="previous" title="Implementation-defined behavior"> +<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="Implementation-limits"></a> +<div class="header"> +<p> +Next: <a href="Obsolete-Features.html#Obsolete-Features" accesskey="n" rel="next">Obsolete Features</a>, Previous: <a href="Implementation_002ddefined-behavior.html#Implementation_002ddefined-behavior" accesskey="p" rel="previous">Implementation-defined behavior</a>, Up: <a href="Implementation-Details.html#Implementation-Details" accesskey="u" rel="up">Implementation Details</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="Implementation-limits-1"></a> +<h3 class="section">11.2 Implementation limits</h3> +<a name="index-implementation-limits"></a> + +<p>CPP has a small number of internal limits. This section lists the +limits which the C standard requires to be no lower than some minimum, +and all the others known. It is intended that there should be as few limits +as possible. If you encounter an undocumented or inconvenient limit, +please report that as a bug. See <a href="http://gcc.gnu.org/onlinedocs/gcc/Bugs.html#Bugs">Reporting Bugs</a> in <cite>Using +the GNU Compiler Collection (GCC)</cite>. +</p> +<p>Where we say something is limited <em>only by available memory</em>, that +means that internal data structures impose no intrinsic limit, and space +is allocated with <code>malloc</code> or equivalent. The actual limit will +therefore depend on many things, such as the size of other things +allocated by the compiler at the same time, the amount of memory +consumed by other processes on the same computer, etc. +</p> +<ul> +<li> Nesting levels of ‘<samp>#include</samp>’ files. + +<p>We impose an arbitrary limit of 200 levels, to avoid runaway recursion. +The standard requires at least 15 levels. +</p> +</li><li> Nesting levels of conditional inclusion. + +<p>The C standard mandates this be at least 63. CPP is limited only by +available memory. +</p> +</li><li> Levels of parenthesized expressions within a full expression. + +<p>The C standard requires this to be at least 63. In preprocessor +conditional expressions, it is limited only by available memory. +</p> +</li><li> Significant initial characters in an identifier or macro name. + +<p>The preprocessor treats all characters as significant. The C standard +requires only that the first 63 be significant. +</p> +</li><li> Number of macros simultaneously defined in a single translation unit. + +<p>The standard requires at least 4095 be possible. CPP is limited only +by available memory. +</p> +</li><li> Number of parameters in a macro definition and arguments in a macro call. + +<p>We allow <code>USHRT_MAX</code>, which is no smaller than 65,535. The minimum +required by the standard is 127. +</p> +</li><li> Number of characters on a logical source line. + +<p>The C standard requires a minimum of 4096 be permitted. CPP places +no limits on this, but you may get incorrect column numbers reported in +diagnostics for lines longer than 65,535 characters. +</p> +</li><li> Maximum size of a source file. + +<p>The standard does not specify any lower limit on the maximum size of a +source file. GNU cpp maps files into memory, so it is limited by the +available address space. This is generally at least two gigabytes. +Depending on the operating system, the size of physical memory may or +may not be a limitation. +</p> +</li></ul> + +<hr> +<div class="header"> +<p> +Next: <a href="Obsolete-Features.html#Obsolete-Features" accesskey="n" rel="next">Obsolete Features</a>, Previous: <a href="Implementation_002ddefined-behavior.html#Implementation_002ddefined-behavior" accesskey="p" rel="previous">Implementation-defined behavior</a>, Up: <a href="Implementation-Details.html#Implementation-Details" accesskey="u" rel="up">Implementation Details</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> + + + +</body> +</html> |