You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
104 lines
5.2 KiB
HTML
104 lines
5.2 KiB
HTML
4 years ago
|
<html lang="en">
|
||
|
|
<head>
|
||
|
|
<title>The GNU C Preprocessor Internals</title>
|
||
|
|
<meta http-equiv="Content-Type" content="text/html">
|
||
|
|
<meta name="description" content="The GNU C Preprocessor Internals">
|
||
|
|
<meta name="generator" content="makeinfo 4.13">
|
||
|
|
<link title="Top" rel="start" href="#Top">
|
||
|
|
<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
|
||
|
|
<meta http-equiv="Content-Style-Type" content="text/css">
|
||
|
|
<style type="text/css"><!--
|
||
|
|
pre.display { font-family:inherit }
|
||
|
|
pre.format { font-family:inherit }
|
||
|
|
pre.smalldisplay { font-family:inherit; font-size:smaller }
|
||
|
|
pre.smallformat { font-family:inherit; font-size:smaller }
|
||
|
|
pre.smallexample { font-size:smaller }
|
||
|
|
pre.smalllisp { font-size:smaller }
|
||
|
|
span.sc { font-variant:small-caps }
|
||
|
|
span.roman { font-family:serif; font-weight:normal; }
|
||
|
|
span.sansserif { font-family:sans-serif; font-weight:normal; }
|
||
|
|
--></style>
|
||
|
|
</head>
|
||
|
|
<body>
|
||
|
|
<h1 class="settitle">The GNU C Preprocessor Internals</h1>
|
||
|
|
<div class="contents">
|
||
|
|
<h2>Table of Contents</h2>
|
||
|
|
<ul>
|
||
|
|
<li><a name="toc_Top" href="index.html#Top">The GNU C Preprocessor Internals</a>
|
||
|
|
<li><a name="toc_Top" href="index.html#Top">1 Cpplib—the GNU C Preprocessor</a>
|
||
|
|
<li><a name="toc_Conventions" href="Conventions.html#Conventions">Conventions</a>
|
||
|
|
<li><a name="toc_Lexer" href="Lexer.html#Lexer">The Lexer</a>
|
||
|
|
<ul>
|
||
|
|
<li><a href="Lexer.html#Lexer">Overview</a>
|
||
|
|
<li><a href="Lexer.html#Lexer">Lexing a token</a>
|
||
|
|
<li><a href="Lexer.html#Lexer">Lexing a line</a>
|
||
|
|
</li></ul>
|
||
|
|
<li><a name="toc_Hash-Nodes" href="Hash-Nodes.html#Hash-Nodes">Hash Nodes</a>
|
||
|
|
<li><a name="toc_Macro-Expansion" href="Macro-Expansion.html#Macro-Expansion">Macro Expansion Algorithm</a>
|
||
|
|
<ul>
|
||
|
|
<li><a href="Macro-Expansion.html#Macro-Expansion">Internal representation of macros</a>
|
||
|
|
<li><a href="Macro-Expansion.html#Macro-Expansion">Macro expansion overview</a>
|
||
|
|
<li><a href="Macro-Expansion.html#Macro-Expansion">Scanning the replacement list for macros to expand</a>
|
||
|
|
<li><a href="Macro-Expansion.html#Macro-Expansion">Looking for a function-like macro's opening parenthesis</a>
|
||
|
|
<li><a href="Macro-Expansion.html#Macro-Expansion">Marking tokens ineligible for future expansion</a>
|
||
|
|
</li></ul>
|
||
|
|
<li><a name="toc_Token-Spacing" href="Token-Spacing.html#Token-Spacing">Token Spacing</a>
|
||
|
|
<li><a name="toc_Line-Numbering" href="Line-Numbering.html#Line-Numbering">Line numbering</a>
|
||
|
|
<ul>
|
||
|
|
<li><a href="Line-Numbering.html#Line-Numbering">Just which line number anyway?</a>
|
||
|
|
<li><a href="Line-Numbering.html#Line-Numbering">Representation of line numbers</a>
|
||
|
|
</li></ul>
|
||
|
|
<li><a name="toc_Guard-Macros" href="Guard-Macros.html#Guard-Macros">The Multiple-Include Optimization</a>
|
||
|
|
<li><a name="toc_Files" href="Files.html#Files">File Handling</a>
|
||
|
|
<li><a name="toc_Concept-Index" href="Concept-Index.html#Concept-Index">Concept Index</a>
|
||
|
|
</li></ul>
|
||
|
|
</div>
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
<div class="node">
|
||
|
|
<a name="Top"></a>
|
||
|
|
<p>
|
||
|
|
Next: <a rel="next" accesskey="n" href="Conventions.html#Conventions">Conventions</a>,
|
||
|
|
Up: <a rel="up" accesskey="u" href="../index.html#dir">(dir)</a>
|
||
|
|
<hr>
|
||
|
|
</div>
|
||
|
|
|
||
|
|
<h2 class="unnumbered">The GNU C Preprocessor Internals</h2>
|
||
|
|
|
||
|
|
<h2 class="chapter">1 Cpplib—the GNU C Preprocessor</h2>
|
||
|
|
|
||
|
|
<p>The GNU C preprocessor is
|
||
|
|
implemented as a library, <dfn>cpplib</dfn>, so it can be easily shared between
|
||
|
|
a stand-alone preprocessor, and a preprocessor integrated with the C,
|
||
|
|
C++ and Objective-C front ends. It is also available for use by other
|
||
|
|
programs, though this is not recommended as its exposed interface has
|
||
|
|
not yet reached a point of reasonable stability.
|
||
|
|
|
||
|
|
<p>The library has been written to be re-entrant, so that it can be used
|
||
|
|
to preprocess many files simultaneously if necessary. It has also been
|
||
|
|
written with the preprocessing token as the fundamental unit; the
|
||
|
|
preprocessor in previous versions of GCC would operate on text strings
|
||
|
|
as the fundamental unit.
|
||
|
|
|
||
|
|
<p>This brief manual documents the internals of cpplib, and explains some
|
||
|
|
of the tricky issues. It is intended that, along with the comments in
|
||
|
|
the source code, a reasonably competent C programmer should be able to
|
||
|
|
figure out what the code is doing, and why things have been implemented
|
||
|
|
the way they have.
|
||
|
|
|
||
|
|
<ul class="menu">
|
||
|
|
<li><a accesskey="1" href="Conventions.html#Conventions">Conventions</a>: Conventions used in the code.
|
||
|
|
<li><a accesskey="2" href="Lexer.html#Lexer">Lexer</a>: The combined C, C++ and Objective-C Lexer.
|
||
|
|
<li><a accesskey="3" href="Hash-Nodes.html#Hash-Nodes">Hash Nodes</a>: All identifiers are entered into a hash table.
|
||
|
|
<li><a accesskey="4" href="Macro-Expansion.html#Macro-Expansion">Macro Expansion</a>: Macro expansion algorithm.
|
||
|
|
<li><a accesskey="5" href="Token-Spacing.html#Token-Spacing">Token Spacing</a>: Spacing and paste avoidance issues.
|
||
|
|
<li><a accesskey="6" href="Line-Numbering.html#Line-Numbering">Line Numbering</a>: Tracking location within files.
|
||
|
|
<li><a accesskey="7" href="Guard-Macros.html#Guard-Macros">Guard Macros</a>: Optimizing header files with guard macros.
|
||
|
|
<li><a accesskey="8" href="Files.html#Files">Files</a>: File handling.
|
||
|
|
<li><a accesskey="9" href="Concept-Index.html#Concept-Index">Concept Index</a>: Index.
|
||
|
|
</ul>
|
||
|
|
|
||
|
|
</body></html>
|
||
|
|
|