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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>Writing and Generating Documentation</title><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><meta name="keywords" content="ISO C++, documentation, style, docbook, doxygen" /><meta name="keywords" content="ISO C++, library" /><meta name="keywords" content="ISO C++, runtime, library" /><link rel="home" href="../index.html" title="The GNU C++ Library" /><link rel="up" href="appendix_porting.html" title="Appendix B.  Porting and Maintenance" /><link rel="prev" href="appendix_porting.html" title="Appendix B.  Porting and Maintenance" /><link rel="next" href="internals.html" title="Porting to New Hardware or Operating Systems" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Writing and Generating Documentation</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="appendix_porting.html">Prev</a> </td><th width="60%" align="center">Appendix B. 
Porting and Maintenance
</th><td width="20%" align="right"> <a accesskey="n" href="internals.html">Next</a></td></tr></table><hr /></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="appendix.porting.doc"></a>Writing and Generating Documentation</h2></div></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="doc.intro"></a>Introduction</h3></div></div></div><p>
Documentation for the GNU C++ Library is created from three
independent sources: a manual, a FAQ, and an API reference.
</p><p>
The sub-directory <code class="filename">doc</code>
within the main source directory contains
<code class="filename">Makefile.am</code> and
<code class="filename">Makefile.in</code>, which provide rules for
generating documentation, described in excruciating detail
below. The <code class="filename">doc</code>
sub-directory also contains three directories: <code class="filename">doxygen</code>, which contains scripts and
fragments for <span class="command"><strong>doxygen</strong></span>, <code class="filename">html</code>, which contains an html
version of the manual, and <code class="filename">xml</code>, which contains an xml version
of the manual.
</p><p>
Diverging from established documentation conventions in the rest
of the GCC project, libstdc++ does not use Texinfo as a markup
language. Instead, Docbook is used to create the manual and the
FAQ, and Doxygen is used to construct the API
reference. Although divergent, this conforms to the GNU Project
recommendations as long as the output is of sufficient quality,
as per
<a class="link" href="http://www.gnu.org/prep/standards/standards.html#Documentation" target="_top">
GNU Manuals</a>.
</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="doc.generation"></a>Generating Documentation</h3></div></div></div><p>
Certain Makefile rules are required by the GNU Coding
Standards. These standard rules generate HTML, PDF, XML, or man
files. For each of the generative rules, there is an additional
install rule that is used to install any generated documentation
files into the prescribed installation directory. Files are
installed into <code class="filename">share/doc</code>
or <code class="filename">share/man</code> directories.
</p><p>
The standard Makefile rules are conditionally supported, based
on the results of examining the host environment for
prerequisites at configuration time. If requirements are not
found, the rule is aliased to a dummy rule that does nothing,
and produces no documentation. If the requirements are found,
the rule forwards to a private rule that produces the requested
documentation.
</p><p>
For more details on what prerequisites were found and where,
please consult the file <code class="filename">config.log</code> in the
libstdc++ build directory. Compare this log to what is expected
for the relevant Makefile conditionals:
<code class="literal">BUILD_INFO</code>, <code class="literal">BUILD_XML</code>,
<code class="literal">BUILD_HTML</code>, <code class="literal">BUILD_MAN</code>,
<code class="literal">BUILD_PDF</code>, and <code class="literal">BUILD_EPUB</code>.
</p><p>
Supported Makefile rules:
</p><div class="variablelist"><dl class="variablelist"><dt><span class="term">
<span class="emphasis"><em>make html</em></span>
, </span><span class="term">
<span class="emphasis"><em>make install-html</em></span>
</span></dt><dd><p>
Generates multi-page HTML documentation, and installs it
in the following directories:
</p><p>
<code class="filename">doc/libstdc++/libstdc++-api.html</code>
</p><p>
<code class="filename">doc/libstdc++/libstdc++-manual.html</code>
</p></dd><dt><span class="term">
<span class="emphasis"><em>make pdf</em></span>
, </span><span class="term">
<span class="emphasis"><em>make install-pdf</em></span>
</span></dt><dd><p>
Generates indexed PDF documentation, and installs it as
the following files:
</p><p>
<code class="filename">doc/libstdc++/libstdc++-api.pdf</code>
</p><p>
<code class="filename">doc/libstdc++/libstdc++-manual.pdf</code>
</p></dd><dt><span class="term">
<span class="emphasis"><em>make man</em></span>
, </span><span class="term">
<span class="emphasis"><em>make install-man</em></span>
</span></dt><dd><p>
Generates man pages, and installs it in the following directory:
</p><p>
<code class="filename">man/man3/</code>
</p><p>
The generated man pages are namespace-qualified, so to look at
the man page for <code class="classname">vector</code>, one would use
<span class="command"><strong>man std::vector</strong></span>.
</p></dd><dt><span class="term">
<span class="emphasis"><em>make epub</em></span>
, </span><span class="term">
<span class="emphasis"><em>make install-epub</em></span>
</span></dt><dd><p>
Generates documentation in the ebook/portable electronic
reader format called Epub, and installs it as the
following file.
</p><p>
<code class="filename">doc/libstdc++/libstdc++-manual.epub</code>
</p></dd><dt><span class="term">
<span class="emphasis"><em>make xml</em></span>
, </span><span class="term">
<span class="emphasis"><em>make install-xml</em></span>
</span></dt><dd><p>
Generates single-file XML documentation, and installs it
as the following files:
</p><p>
<code class="filename">doc/libstdc++/libstdc++-api-single.xml</code>
</p><p>
<code class="filename">doc/libstdc++/libstdc++-manual-single.xml</code>
</p></dd></dl></div><p>
Makefile rules for several other formats are explicitly not
supported, and are always aliased to dummy rules. These
unsupported formats are: <span class="emphasis"><em>info</em></span>,
<span class="emphasis"><em>ps</em></span>, and <span class="emphasis"><em>dvi</em></span>.
</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="doc.doxygen"></a>Doxygen</h3></div></div></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="doxygen.prereq"></a>Prerequisites</h4></div></div></div><div class="table"><a id="table.doxygen_prereq"></a><p class="title"><strong>Table B.1. Doxygen Prerequisites</strong></p><div class="table-contents"><table class="table" summary="Doxygen Prerequisites" border="1"><colgroup><col align="center" class="c1" /><col align="center" class="c2" /><col align="center" class="c3" /></colgroup><thead><tr><th align="center">Tool</th><th align="center">Version</th><th align="center">Required By</th></tr></thead><tbody><tr><td align="center">coreutils</td><td align="center">8.5</td><td align="center">all</td></tr><tr><td align="center">bash</td><td align="center">4.1</td><td align="center">all</td></tr><tr><td align="center">doxygen</td><td align="center">1.7.6.1</td><td align="center">all</td></tr><tr><td align="center">graphviz</td><td align="center">2.26</td><td align="center">graphical hierarchies</td></tr><tr><td align="center">pdflatex</td><td align="center">2007-59</td><td align="center">pdf output</td></tr></tbody></table></div></div><br class="table-break" /><p>
Prerequisite tools are Bash 2.0 or later,
<a class="link" href="https://www.doxygen.nl" target="_top">Doxygen</a>, and
the <a class="link" href="http://www.gnu.org/software/coreutils/" target="_top">GNU
coreutils</a>. (GNU versions of find, xargs, and possibly
sed and grep are used, just because the GNU versions make
things very easy.)
</p><p>
To generate the pretty pictures and hierarchy
graphs, the
<a class="link" href="http://www.graphviz.org" target="_top">Graphviz</a> package
will need to be installed. For PDF
output, <a class="link" href="http://www.tug.org/applications/pdftex/" target="_top">
pdflatex</a> is required as well as a number of TeX packages
such as <span class="package">texlive-xtab</span> and
<span class="package">texlive-tocloft</span>.
</p><p>
Be warned the PDF file generated via doxygen is extremely
large. At last count, the PDF file is over three thousand
pages. Generating this document taxes the underlying TeX
formatting system, and will require the expansion of TeX's memory
capacity. Specifically, the <code class="literal">pool_size</code>
variable in the configuration file <code class="filename">texmf.cnf</code> may
need to be increased by a minimum factor of two.
</p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="doxygen.rules"></a>Generating the Doxygen Files</h4></div></div></div><p>
The following Makefile rules run Doxygen to generate HTML
docs, XML docs, XML docs as a single file, PDF docs, and the
man pages. These rules are not conditional! If the required
tools are not found, or are the wrong versions, the rule may
end in an error.
</p><p>
</p><pre class="screen"><strong class="userinput"><code>make doc-html-doxygen</code></strong></pre><p>
</p><p>
</p><pre class="screen"><strong class="userinput"><code>make doc-xml-doxygen</code></strong></pre><p>
</p><p>
</p><pre class="screen"><strong class="userinput"><code>make doc-xml-single-doxygen</code></strong></pre><p>
</p><p>
</p><pre class="screen"><strong class="userinput"><code>make doc-pdf-doxygen</code></strong></pre><p>
</p><p>
</p><pre class="screen"><strong class="userinput"><code>make doc-man-doxygen</code></strong></pre><p>
</p><p>
Generated files are output into separate sub directories of
<code class="filename">doc/doxygen/</code> in the
build directory, based on the output format. For instance, the
HTML docs will be in <code class="filename">doc/doxygen/html</code>.
</p><p>
Careful observers will see that the Makefile rules simply call
a script from the source tree, <code class="filename">run_doxygen</code>, which
does the actual work of running Doxygen and then (most
importantly) massaging the output files. If for some reason
you prefer to not go through the Makefile, you can call this
script directly. (Start by passing <code class="literal">--help</code>.)
</p><p>
If you wish to tweak the Doxygen settings, do so by editing
<code class="filename">doc/doxygen/user.cfg.in</code>. Notes to fellow
library hackers are written in triple-# comments.
</p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="doxygen.debug"></a>Debugging Generation</h4></div></div></div><p>
Sometimes, mis-configuration of the pre-requisite tools can
lead to errors when attempting to build the
documentation. Here are some of the obvious errors, and ways
to fix some common issues that may appear quite cryptic.
</p><p>
First, if using a rule like <code class="code">make pdf</code>, try to
narrow down the scope of the error to either docbook
(<code class="code">make doc-pdf-docbook</code>) or doxygen (<code class="code">make
doc-pdf-doxygen</code>).
</p><p>
Working on the doxygen path only, closely examine the
contents of the following build directory: <code class="filename">build/target/libstdc++-v3/doc/doxygen/latex</code>.
Pay attention to three files enclosed within, annotated as follows.
</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
<span class="emphasis"><em>refman.tex</em></span>
</p><p>
The actual latex file, or partial latex file. This is generated
via <span class="command"><strong>doxygen</strong></span>, and is the LaTeX version of the
Doxygen XML file <code class="filename">libstdc++-api.xml</code>. Go to a specific
line, and look at the generated LaTeX, and try to deduce what
markup in <code class="filename">libstdc++-api.xml</code> is causing it.
</p></li><li class="listitem"><p>
<span class="emphasis"><em>refman.log</em></span>
</p><p>
A log created by <span class="command"><strong>latex</strong></span> as it processes the
<code class="filename">refman.tex</code> file. If generating the PDF fails
look at the end of this file for errors such as:
</p><pre class="screen">
! LaTeX Error: File `xtab.sty' not found.
</pre><p>
This indicates a required TeX package is missing. For the example
above the <span class="package">texlive-xtab</span> package needs to be
installed.
</p></li><li class="listitem"><p>
<span class="emphasis"><em>refman.out</em></span>
</p><p>
A log of the compilation of the converted LaTeX form to PDF. This
is a linear list, from the beginning of the
<code class="filename">refman.tex</code> file: the last entry of this file
should be the end of the LaTeX file. If it is truncated, then you
know that the last entry is the last part of the generated LaTeX
source file that is valid. Often this file contains an error with
a specific line number of <code class="filename">refman.tex</code> that is
incorrect, or will have clues at the end of the file with the dump
of the memory usage of LaTeX.
</p></li></ul></div><p>
If the error at hand is not obvious after examination, a
fall-back strategy is to start commenting out the doxygen
input sources, which can be found in
<code class="filename">doc/doxygen/user.cfg.in</code>, look for the
<code class="literal">INPUT</code> tag. Start by commenting out whole
directories of header files, until the offending header is
identified. Then, read the latex log files to try and find
surround text, and look for that in the offending header.
</p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="doxygen.markup"></a>Markup</h4></div></div></div><p>
In general, libstdc++ files should be formatted according to
the rules found in the
<a class="link" href="source_code_style.html" title="Coding Style">Coding Standard</a>. Before
any doxygen-specific formatting tweaks are made, please try to
make sure that the initial formatting is sound.
</p><p>
Adding Doxygen markup to a file (informally called
<span class="quote"><span class="quote">doxygenating</span></span>) is very simple. See the
<a class="link" href="https://www.doxygen.nl/download.html#latestman" target="_top">Doxygen
manual</a> for details.
We try to use a very-recent version of Doxygen.
</p><p>
For classes, use
<code class="classname">deque</code>/<code class="classname">vector</code>/<code class="classname">list</code>
and <code class="classname">std::pair</code> as examples. For
functions, see their member functions, and the free functions
in <code class="filename">stl_algobase.h</code>. Member
functions of other container-like types should read similarly to
these member functions.
</p><p>
Some commentary to accompany
the first list in the <a class="link" href="https://www.doxygen.nl/manual/docblocks.html" target="_top">Special
Documentation Blocks</a> section of the Doxygen manual:
</p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>For longer comments, use the Javadoc style...</p></li><li class="listitem"><p>
...not the Qt style. The intermediate *'s are preferred.
</p></li><li class="listitem"><p>
Use the triple-slash style only for one-line comments (the
<span class="quote"><span class="quote">brief</span></span> mode).
</p></li><li class="listitem"><p>
This is disgusting. Don't do this.
</p></li></ol></div><p>
Some specific guidelines:
</p><p>
Use the @-style of commands, not the !-style. Please be
careful about whitespace in your markup comments. Most of the
time it doesn't matter; doxygen absorbs most whitespace, and
both HTML and *roff are agnostic about whitespace. However,
in &lt;pre&gt; blocks and @code/@endcode sections, spacing can
have <span class="quote"><span class="quote">interesting</span></span> effects.
</p><p>
Use either kind of grouping, as
appropriate. <code class="filename">doxygroups.cc</code> exists for this
purpose. See <code class="filename">stl_iterator.h</code>
for a good example of the <span class="quote"><span class="quote">other</span></span> kind of grouping.
</p><p>
Please use markup tags like @p and @a when referring to things
such as the names of function parameters. Use @e for emphasis
when necessary. Use @c to refer to other standard names.
(Examples of all these abound in the present code.)
</p><p>
Complicated math functions should use the multi-line format.
An example from <code class="filename">random.h</code>:
</p><p>
</p><div class="literallayout"><p><br />
/**<br />
 * @brief A model of a linear congruential random number generator.<br />
 *<br />
 * @f[<br />
 *     x_{i+1}\leftarrow(ax_{i} + c) \bmod m<br />
 * @f]<br />
 */<br />
</p></div><p>
</p><p>
One area of note is the markup required for
<code class="literal">@file</code> markup in header files. Two details
are important: for filenames that have the same name in
multiple directories, include part of the installed path to
disambiguate. For example:
</p><p>
</p><div class="literallayout"><p><br />
/** @file debug/vector<br />
 *  This file is a GNU debug extension to the Standard C++ Library.<br />
 */<br />
</p></div><p>
</p><p>
The other relevant detail for header files is the use of a
libstdc++-specific doxygen alias that helps distinguish
between public header files (like <code class="filename">random</code>)
from implementation or private header files (like
<code class="filename">bits/c++config.h</code>.) This alias is spelled
<code class="literal">@headername</code> and can take one or two
arguments that detail the public header file or files that
should be included to use the contents of the file. All header
files that are not intended for direct inclusion must use
<code class="literal">headername</code> in the <code class="literal">file</code>
block. An example:
</p><p>
</p><div class="literallayout"><p><br />
/** @file bits/basic_string.h<br />
 *  This is an internal header file, included by other library headers.<br />
 *  Do not attempt to use it directly. @headername{string}<br />
 */<br />
</p></div><p>
</p><p>
Be careful about using certain, special characters when
writing Doxygen comments. Single and double quotes, and
separators in filenames are two common trouble spots. When in
doubt, consult the following table.
</p><div class="table"><a id="table.doxygen_cmp"></a><p class="title"><strong>Table B.2. HTML to Doxygen Markup Comparison</strong></p><div class="table-contents"><table class="table" summary="HTML to Doxygen Markup Comparison" border="1"><colgroup><col align="left" class="c1" /><col align="left" class="c2" /></colgroup><thead><tr><th align="left">HTML</th><th align="left">Doxygen</th></tr></thead><tbody><tr><td align="left">\</td><td align="left">\\</td></tr><tr><td align="left">"</td><td align="left">\"</td></tr><tr><td align="left">'</td><td align="left">\'</td></tr><tr><td align="left">&lt;i&gt;</td><td align="left">@a word</td></tr><tr><td align="left">&lt;b&gt;</td><td align="left">@b word</td></tr><tr><td align="left">&lt;code&gt;</td><td align="left">@c word</td></tr><tr><td align="left">&lt;em&gt;</td><td align="left">@a word</td></tr><tr><td align="left">&lt;em&gt;</td><td align="left">&lt;em&gt;two words or more&lt;/em&gt;</td></tr></tbody></table></div></div><br class="table-break" /></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="doc.docbook"></a>Docbook</h3></div></div></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="docbook.prereq"></a>Prerequisites</h4></div></div></div><div class="table"><a id="table.docbook_prereq"></a><p class="title"><strong>Table B.3. Docbook Prerequisites</strong></p><div class="table-contents"><table class="table" summary="Docbook Prerequisites" border="1"><colgroup><col align="center" class="c1" /><col align="center" class="c2" /><col align="center" class="c3" /></colgroup><thead><tr><th align="center">Tool</th><th align="center">Version</th><th align="center">Required By</th></tr></thead><tbody><tr><td align="center">docbook5-style-xsl</td><td align="center">1.76.1</td><td align="center">all</td></tr><tr><td align="center">xsltproc</td><td align="center">1.1.26</td><td align="center">all</td></tr><tr><td align="center">xmllint</td><td align="center">2.7.7</td><td align="center">validation</td></tr><tr><td align="center">dblatex</td><td align="center">0.3</td><td align="center">pdf output</td></tr><tr><td align="center">pdflatex</td><td align="center">2007-59</td><td align="center">pdf output</td></tr><tr><td align="center">docbook2X</td><td align="center">0.8.8</td><td align="center">info output</td></tr><tr><td align="center">epub3 stylesheets</td><td align="center">b3</td><td align="center">epub output</td></tr></tbody></table></div></div><br class="table-break" /><p>
Editing the DocBook sources requires an XML editor. Many
exist: some notable options
include <span class="command"><strong>emacs</strong></span>, <span class="application">Kate</span>,
or <span class="application">Conglomerate</span>.
</p><p>
Some editors support special <span class="quote"><span class="quote">XML Validation</span></span>
modes that can validate the file as it is
produced. Recommended is the <span class="command"><strong>nXML Mode</strong></span>
for <span class="command"><strong>emacs</strong></span>.
</p><p>
Besides an editor, additional DocBook files and XML tools are
also required.
</p><p>
Access to the DocBook 5.0 stylesheets and schema is required. The
stylesheets are usually packaged by vendor, in something
like <code class="filename">docbook5-style-xsl</code>. To exactly match
generated output, please use a version of the stylesheets
equivalent
to <code class="filename">docbook5-style-xsl-1.75.2-3</code>. The
installation directory for this package corresponds to
the <code class="literal">XSL_STYLE_DIR</code>
in <code class="filename">doc/Makefile.am</code> and defaults
to <code class="filename">/usr/share/sgml/docbook/xsl-ns-stylesheets</code>.
</p><p>
For processing XML, an XSLT processor and some style
sheets are necessary. Defaults are <span class="command"><strong>xsltproc</strong></span>
provided by <code class="filename">libxslt</code>.
</p><p>
For validating the XML document, you'll need
something like <span class="command"><strong>xmllint</strong></span> and access to the
relevant DocBook schema. These are provided
by a vendor package like <code class="filename">libxml2</code> and <code class="filename">docbook5-schemas-5.0-4</code>
</p><p>
For PDF output, something that transforms valid Docbook XML to PDF is
required. Possible solutions include <a class="link" href="http://dblatex.sourceforge.net" target="_top">dblatex</a>,
<span class="command"><strong>xmlto</strong></span>, or <span class="command"><strong>prince</strong></span>. Of
these, <span class="command"><strong>dblatex</strong></span> is the default.
Please consult the <code class="email">&lt;<a class="email" href="mailto:libstdc++@gcc.gnu.org">libstdc++@gcc.gnu.org</a>&gt;</code> list when
preparing printed manuals for current best practice and
suggestions.
</p><p>
For Texinfo output, something that transforms valid Docbook
XML to Texinfo is required. The default choice is <a class="link" href="http://docbook2x.sourceforge.net/" target="_top">docbook2X</a>.
</p><p>
For epub output, the <a class="link" href="https://sourceforge.net/projects/docbook/files/epub3/" target="_top">stylesheets</a> for EPUB3 are required. These stylesheets are still in development. To validate the created file, <a class="link" href="https://github.com/w3c/epubcheck" target="_top">epubcheck</a> is necessary.
</p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="docbook.rules"></a>Generating the DocBook Files</h4></div></div></div><p>
The following Makefile rules generate (in order): an HTML
version of all the DocBook documentation, a PDF version of the
same, and a single XML document. These rules are not
conditional! If the required tools are not found, or are the
wrong versions, the rule may end in an error.
</p><p>
</p><pre class="screen"><strong class="userinput"><code>make doc-html-docbook</code></strong></pre><p>
</p><p>
</p><pre class="screen"><strong class="userinput"><code>make doc-pdf-docbook</code></strong></pre><p>
</p><p>
</p><pre class="screen"><strong class="userinput"><code>make doc-xml-single-docbook</code></strong></pre><p>
</p><p>
Generated files are output into separate sub-directores of
<code class="filename">doc/docbook/</code> in the
build directory, based on the output format. For instance, the
HTML docs will be in <code class="filename">doc/docbook/html</code>.
</p><p>
The </p><pre class="screen">doc-html-docbook-regenerate</pre><p> target will generate
the HTML files and copy them back to the libstdc++ source tree.
This can be used to update the HTML files that are checked in to
version control.
</p><p>
If the Docbook stylesheets are installed in a custom location,
one can use the variable <code class="literal">XSL_STYLE_DIR</code> to
override the Makefile defaults. For example:
</p><pre class="screen">
<strong class="userinput"><code>
make <code class="literal">XSL_STYLE_DIR="/usr/share/xml/docbook/stylesheet/nwalsh"</code> doc-html-docbook
</code></strong>
</pre></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="docbook.debug"></a>Debugging Generation</h4></div></div></div><p>
Sometimes, mis-configuration of the pre-requisite tools can
lead to errors when attempting to build the
documentation. Here are some of the obvious errors, and ways
to fix some common issues that may appear quite cryptic.
</p><p>
First, if using a rule like <code class="code">make pdf</code>, try to
narrow down the scope of the error to either docbook
(<code class="code">make doc-pdf-docbook</code>) or doxygen (<code class="code">make
doc-pdf-doxygen</code>).
</p><p>
Working on the docbook path only, closely examine the
contents of the following build directory:
<code class="filename">build/target/libstdc++-v3/doc/docbook/latex</code>.
Pay attention to three files enclosed within, annotated as follows.
</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
<span class="emphasis"><em>spine.tex</em></span>
</p><p>
The actual latex file, or partial latex file. This is generated
via <span class="command"><strong>dblatex</strong></span>, and is the LaTeX version of the
DocBook XML file <code class="filename">spine.xml</code>. Go to a specific
line, and look at the generated LaTeX, and try to deduce what
markup in <code class="filename">spine.xml</code> is causing it.
</p></li><li class="listitem"><p>
<span class="emphasis"><em>spine.out</em></span>
</p><p>
A log of the conversion from the XML form to the LaTeX form. This
is a linear list, from the beginning of the
<code class="filename">spine.xml</code> file: the last entry of this file
should be the end of the DocBook file. If it is truncated, then
you know that the last entry is the last part of the XML source
file that is valid. The error is after this point.
</p></li><li class="listitem"><p>
<span class="emphasis"><em>spine.log</em></span>
</p><p>
A log of the compilation of the converted LaTeX form to pdf. This
is a linear list, from the beginning of the
<code class="filename">spine.tex</code> file: the last entry of this file
should be the end of the LaTeX file. If it is truncated, then you
know that the last entry is the last part of the generated LaTeX
source file that is valid. Often this file contains an error with
a specific line number of <code class="filename">spine.tex</code> that is
incorrect.
</p></li></ul></div><p>
If the error at hand is not obvious after examination, or if one
encounters the inscruitable <span class="quote"><span class="quote">Incomplete
\ifmmode</span></span> error, a fall-back strategy is to start
commenting out parts of the XML document (regardless of what
this does to over-all document validity). Start by
commenting out each of the largest parts of the
<code class="filename">spine.xml</code> file, section by section,
until the offending section is identified.
</p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="docbook.validation"></a>Editing and Validation</h4></div></div></div><p>
After editing the xml sources, please make sure that the XML
documentation and markup is still valid. This can be
done easily, with the following validation rule:
</p><pre class="screen">
<strong class="userinput"><code>make doc-xml-validate-docbook</code></strong>
</pre><p>
This is equivalent to doing:
</p><pre class="screen">
<strong class="userinput"><code>
xmllint --noout --valid <code class="filename">xml/index.xml</code>
</code></strong>
</pre><p>
Please note that individual sections and chapters of the
manual can be validated by substituting the file desired for
<code class="filename">xml/index.xml</code> in the command
above. Reducing scope in this manner can be helpful when
validation on the entire manual fails.
</p><p>
All Docbook xml sources should always validate. No excuses!
</p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="docbook.examples"></a>File Organization and Basics</h4></div></div></div><div class="literallayout"><p><br />
      <span class="emphasis"><em>Which files are important</em></span><br />
<br />
      All Docbook files are in the directory<br />
      libstdc++-v3/doc/xml<br />
<br />
      Inside this directory, the files of importance:<br />
      spine.xml   - index to documentation set<br />
      manual/spine.xml  - index to manual<br />
      manual/*.xml   - individual chapters and sections of the manual<br />
      faq.xml   - index to FAQ<br />
      api.xml   - index to source level / API<br />
<br />
      All *.txml files are template xml files, i.e., otherwise empty files with<br />
      the correct structure, suitable for filling in with new information.<br />
<br />
      <span class="emphasis"><em>Canonical Writing Style</em></span><br />
<br />
      class template<br />
      function template<br />
      member function template<br />
      (via C++ Templates, Vandevoorde)<br />
<br />
      class in namespace std: allocator, not std::allocator<br />
<br />
      header file: iostream, not &lt;iostream&gt;<br />
<br />
<br />
      <span class="emphasis"><em>General structure</em></span><br />
<br />
      &lt;set&gt;<br />
      &lt;book&gt;<br />
      &lt;/book&gt;<br />
<br />
      &lt;book&gt;<br />
      &lt;chapter&gt;<br />
      &lt;/chapter&gt;<br />
      &lt;/book&gt;<br />
<br />
      &lt;book&gt;<br />
      &lt;part&gt;<br />
      &lt;chapter&gt;<br />
      &lt;section&gt;<br />
      &lt;/section&gt;<br />
<br />
      &lt;sect1&gt;<br />
      &lt;/sect1&gt;<br />
<br />
      &lt;sect1&gt;<br />
      &lt;sect2&gt;<br />
      &lt;/sect2&gt;<br />
      &lt;/sect1&gt;<br />
      &lt;/chapter&gt;<br />
<br />
      &lt;chapter&gt;<br />
      &lt;/chapter&gt;<br />
      &lt;/part&gt;<br />
      &lt;/book&gt;<br />
<br />
      &lt;/set&gt;<br />
    </p></div></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="docbook.markup"></a>Markup By Example</h4></div></div></div><p>
Complete details on Docbook markup can be found in the
<a class="link" href="https://tdg.docbook.org/tdg/5.0/ref-elements.html" target="_top">DocBook Element Reference</a>.
An incomplete reference for HTML to Docbook conversion is
detailed in the table below.
</p><div class="table"><a id="table.docbook_cmp"></a><p class="title"><strong>Table B.4. HTML to Docbook XML Markup Comparison</strong></p><div class="table-contents"><table class="table" summary="HTML to Docbook XML Markup Comparison" border="1"><colgroup><col align="left" class="c1" /><col align="left" class="c2" /></colgroup><thead><tr><th align="left">HTML</th><th align="left">Docbook</th></tr></thead><tbody><tr><td align="left">&lt;p&gt;</td><td align="left">&lt;para&gt;</td></tr><tr><td align="left">&lt;pre&gt;</td><td align="left">&lt;computeroutput&gt;, &lt;programlisting&gt;,
&lt;literallayout&gt;</td></tr><tr><td align="left">&lt;ul&gt;</td><td align="left">&lt;itemizedlist&gt;</td></tr><tr><td align="left">&lt;ol&gt;</td><td align="left">&lt;orderedlist&gt;</td></tr><tr><td align="left">&lt;il&gt;</td><td align="left">&lt;listitem&gt;</td></tr><tr><td align="left">&lt;dl&gt;</td><td align="left">&lt;variablelist&gt;</td></tr><tr><td align="left">&lt;dt&gt;</td><td align="left">&lt;term&gt;</td></tr><tr><td align="left">&lt;dd&gt;</td><td align="left">&lt;listitem&gt;</td></tr><tr><td align="left">&lt;a href=""&gt;</td><td align="left">&lt;ulink url=""&gt;</td></tr><tr><td align="left">&lt;code&gt;</td><td align="left">&lt;literal&gt;, &lt;programlisting&gt;</td></tr><tr><td align="left">&lt;strong&gt;</td><td align="left">&lt;emphasis&gt;</td></tr><tr><td align="left">&lt;em&gt;</td><td align="left">&lt;emphasis&gt;</td></tr><tr><td align="left">"</td><td align="left">&lt;quote&gt;</td></tr></tbody></table></div></div><br class="table-break" /><p>
And examples of detailed markup for which there are no real HTML
equivalents are listed in the table below.
</p><div class="table"><a id="table.docbook_elem"></a><p class="title"><strong>Table B.5. Docbook XML Element Use</strong></p><div class="table-contents"><table class="table" summary="Docbook XML Element Use" border="1"><colgroup><col align="left" class="c1" /><col align="left" class="c2" /></colgroup><thead><tr><th align="left">Element</th><th align="left">Use</th></tr></thead><tbody><tr><td align="left">&lt;structname&gt;</td><td align="left">&lt;structname&gt;char_traits&lt;/structname&gt;</td></tr><tr><td align="left">&lt;classname&gt;</td><td align="left">&lt;classname&gt;string&lt;/classname&gt;</td></tr><tr><td align="left">&lt;function&gt;</td><td align="left">
<p>&lt;function&gt;clear()&lt;/function&gt;</p>
<p>&lt;function&gt;fs.clear()&lt;/function&gt;</p>
</td></tr><tr><td align="left">&lt;type&gt;</td><td align="left">&lt;type&gt;long long&lt;/type&gt;</td></tr><tr><td align="left">&lt;varname&gt;</td><td align="left">&lt;varname&gt;fs&lt;/varname&gt;</td></tr><tr><td align="left">&lt;literal&gt;</td><td align="left">
<p>&lt;literal&gt;-Weffc++&lt;/literal&gt;</p>
<p>&lt;literal&gt;rel_ops&lt;/literal&gt;</p>
</td></tr><tr><td align="left">&lt;constant&gt;</td><td align="left">
<p>&lt;constant&gt;_GNU_SOURCE&lt;/constant&gt;</p>
<p>&lt;constant&gt;3.0&lt;/constant&gt;</p>
</td></tr><tr><td align="left">&lt;command&gt;</td><td align="left">&lt;command&gt;g++&lt;/command&gt;</td></tr><tr><td align="left">&lt;errortext&gt;</td><td align="left">&lt;errortext&gt;In instantiation of&lt;/errortext&gt;</td></tr><tr><td align="left">&lt;filename&gt;</td><td align="left">
<p>&lt;filename class="headerfile"&gt;ctype.h&lt;/filename&gt;</p>
<p>&lt;filename class="directory"&gt;/home/gcc/build&lt;/filename&gt;</p>
<p>&lt;filename class="libraryfile"&gt;libstdc++.so&lt;/filename&gt;</p>
</td></tr></tbody></table></div></div><br class="table-break" /></div></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="appendix_porting.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="appendix_porting.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="internals.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Appendix B. 
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