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diff --git a/gcc-4.4.3/libstdc++-v3/doc/html/manual/bk01pt12ch30s02.html b/gcc-4.4.3/libstdc++-v3/doc/html/manual/bk01pt12ch30s02.html deleted file mode 100644 index cb2031718..000000000 --- a/gcc-4.4.3/libstdc++-v3/doc/html/manual/bk01pt12ch30s02.html +++ /dev/null @@ -1,55 +0,0 @@ -<?xml version="1.0" encoding="UTF-8" standalone="no"?> -<!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>Semantics</title><meta name="generator" content="DocBook XSL Stylesheets V1.74.0" /><meta name="keywords" content=" C++ , library , debug " /><meta name="keywords" content=" ISO C++ , library " /><link rel="home" href="../spine.html" title="The GNU C++ Library Documentation" /><link rel="up" href="debug_mode.html" title="Chapter 30. Debug Mode" /><link rel="prev" href="debug_mode.html" title="Chapter 30. Debug Mode" /><link rel="next" href="bk01pt12ch30s03.html" title="Using" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Semantics</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="debug_mode.html">Prev</a> </td><th width="60%" align="center">Chapter 30. Debug Mode</th><td width="20%" align="right"> <a accesskey="n" href="bk01pt12ch30s03.html">Next</a></td></tr></table><hr /></div><div class="sect1" lang="en" xml:lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="manual.ext.debug_mode.semantics"></a>Semantics</h2></div></div></div><p> - </p><p>A program that uses the C++ standard library correctly - will maintain the same semantics under debug mode as it had with - the normal (release) library. All functional and exception-handling - guarantees made by the normal library also hold for the debug mode - library, with one exception: performance guarantees made by the - normal library may not hold in the debug mode library. For - instance, erasing an element in a <code class="code">std::list</code> is a - constant-time operation in normal library, but in debug mode it is - linear in the number of iterators that reference that particular - list. So while your (correct) program won't change its results, it - is likely to execute more slowly.</p><p>libstdc++ includes many extensions to the C++ standard library. In - some cases the extensions are obvious, such as the hashed - associative containers, whereas other extensions give predictable - results to behavior that would otherwise be undefined, such as - throwing an exception when a <code class="code">std::basic_string</code> is - constructed from a NULL character pointer. This latter category also - includes implementation-defined and unspecified semantics, such as - the growth rate of a vector. Use of these extensions is not - considered incorrect, so code that relies on them will not be - rejected by debug mode. However, use of these extensions may affect - the portability of code to other implementations of the C++ standard - library, and is therefore somewhat hazardous. For this reason, the - libstdc++ debug mode offers a "pedantic" mode (similar to - GCC's <code class="code">-pedantic</code> compiler flag) that attempts to emulate - the semantics guaranteed by the C++ standard. For - instance, constructing a <code class="code">std::basic_string</code> with a NULL - character pointer would result in an exception under normal mode or - non-pedantic debug mode (this is a libstdc++ extension), whereas - under pedantic debug mode libstdc++ would signal an error. To enable - the pedantic debug mode, compile your program with - both <code class="code">-D_GLIBCXX_DEBUG</code> - and <code class="code">-D_GLIBCXX_DEBUG_PEDANTIC</code> . - (N.B. In GCC 3.4.x and 4.0.0, due to a bug, - <code class="code">-D_GLIBXX_DEBUG_PEDANTIC</code> was also needed. The problem has - been fixed in GCC 4.0.1 and later versions.) </p><p>The following library components provide extra debugging - capabilities in debug mode:</p><div class="itemizedlist"><ul type="disc"><li><p><code class="code">std::basic_string</code> (no safe iterators and see note below)</p></li><li><p><code class="code">std::bitset</code></p></li><li><p><code class="code">std::deque</code></p></li><li><p><code class="code">std::list</code></p></li><li><p><code class="code">std::map</code></p></li><li><p><code class="code">std::multimap</code></p></li><li><p><code class="code">std::multiset</code></p></li><li><p><code class="code">std::set</code></p></li><li><p><code class="code">std::vector</code></p></li><li><p><code class="code">std::unordered_map</code></p></li><li><p><code class="code">std::unordered_multimap</code></p></li><li><p><code class="code">std::unordered_set</code></p></li><li><p><code class="code">std::unordered_multiset</code></p></li></ul></div><p>N.B. although there are precondition checks for some string operations, -e.g. <code class="code">operator[]</code>, -they will not always be run when using the <code class="code">char</code> and -<code class="code">wchar_t</code> specialisations (<code class="code">std::string</code> and -<code class="code">std::wstring</code>). This is because libstdc++ uses GCC's -<code class="code">extern template</code> extension to provide explicit instantiations -of <code class="code">std::string</code> and <code class="code">std::wstring</code>, and those -explicit instantiations don't include the debug-mode checks. If the -containing functions are inlined then the checks will run, so compiling -with <code class="code">-O1</code> might be enough to enable them. Alternatively -<code class="code">-D_GLIBCXX_EXTERN_TEMPLATE=0</code> will suppress the declarations -of the explicit instantiations and cause the functions to be instantiated -with the debug-mode checks included, but this is unsupported and not -guaranteed to work. For full debug-mode support you can use the -<code class="code">__gnu_debug::basic_string</code> debugging container directly, -which always works correctly. -</p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="debug_mode.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="debug_mode.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="bk01pt12ch30s03.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 30. Debug Mode </td><td width="20%" align="center"><a accesskey="h" href="../spine.html">Home</a></td><td width="40%" align="right" valign="top"> Using</td></tr></table></div></body></html> |