Save-and-restore errno more carefully in libstdc++
* doc/xml/manual/diagnostics.xml: Document use of errno. * doc/html/*: Regenerate. * config/locale/generic/c_locale.cc (_Save_errno): New helper. (__convert_to_v): Use _Save_errno. * include/ext/string_conversions.h (__stoa): Only restore errno when it isn't set to non-zero. From-SVN: r228328
This commit is contained in:
Jonathan Wakely
Jonathan Wakely
parent
aabef2de2f
commit
f14decafae
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@ -1,3 +1,12 @@
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2015-10-01 Jonathan Wakely <jwakely@redhat.com>
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* doc/xml/manual/diagnostics.xml: Document use of errno.
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* doc/html/*: Regenerate.
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* config/locale/generic/c_locale.cc (_Save_errno): New helper.
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(__convert_to_v): Use _Save_errno.
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* include/ext/string_conversions.h (__stoa): Only restore errno when
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it isn't set to non-zero.
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2015-09-30 François Dumont <fdumont@gcc.gnu.org>
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Jonathan Wakely <jwakely@redhat.com>
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@ -44,6 +44,16 @@ namespace std _GLIBCXX_VISIBILITY(default)
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{
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_GLIBCXX_BEGIN_NAMESPACE_VERSION
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namespace
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{
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struct _Save_errno
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{
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_Save_errno() : _M_errno(errno) { errno = 0; }
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~_Save_errno() { if (errno == 0) errno = _M_errno; }
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int _M_errno;
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};
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}
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template<>
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void
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__convert_to_v(const char* __s, float& __v, ios_base::iostate& __err,
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@ -59,7 +69,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
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bool __overflow = false;
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#if !__FLT_HAS_INFINITY__
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errno = 0;
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const _Save_errno __save_errno;
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#endif
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#ifdef _GLIBCXX_HAVE_STRTOF
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@ -123,7 +133,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
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char* __sanity;
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#if !__DBL_HAS_INFINITY__
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errno = 0;
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const _Save_errno __save_errno;
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#endif
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__v = strtod(__s, &__sanity);
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@ -167,7 +177,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
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setlocale(LC_ALL, "C");
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#if !__LDBL_HAS_INFINITY__
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errno = 0;
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const _Save_errno __save_errno;
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#endif
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#if defined(_GLIBCXX_HAVE_STRTOLD) && !defined(_GLIBCXX_HAVE_BROKEN_STRTOLD)
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@ -1,5 +1,5 @@
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<?xml version="1.0" encoding="UTF-8" standalone="no"?>
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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>Concept Checking</title><meta name="generator" content="DocBook XSL-NS Stylesheets V1.78.1" /><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="diagnostics.html" title="Chapter 5. Diagnostics" /><link rel="prev" href="diagnostics.html" title="Chapter 5. Diagnostics" /><link rel="next" href="utilities.html" title="Chapter 6. Utilities" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Concept Checking</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="diagnostics.html">Prev</a> </td><th width="60%" align="center">Chapter 5.
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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>Concept Checking</title><meta name="generator" content="DocBook XSL-NS Stylesheets V1.78.1" /><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="diagnostics.html" title="Chapter 5. Diagnostics" /><link rel="prev" href="errno.html" title="Use of errno by the library" /><link rel="next" href="utilities.html" title="Chapter 6. Utilities" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Concept Checking</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="errno.html">Prev</a> </td><th width="60%" align="center">Chapter 5.
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Diagnostics
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</th><td width="20%" align="right"> <a accesskey="n" href="utilities.html">Next</a></td></tr></table><hr /></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="std.diagnostics.concept_checking"></a>Concept Checking</h2></div></div></div><p>
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@ -41,10 +41,7 @@
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for example template argument types may need to be complete when used in
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a template definition, rather than at the point of instantiation.
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There are no plans to address these shortcomings.
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</p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="diagnostics.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="diagnostics.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="utilities.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 5.
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Diagnostics
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|
||||
</td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 6.
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</p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="errno.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="diagnostics.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="utilities.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Use of errno by the library </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 6.
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Utilities
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</td></tr></table></div></body></html>
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@ -1,13 +1,13 @@
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<?xml version="1.0" encoding="UTF-8" standalone="no"?>
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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>Chapter 5. Diagnostics</title><meta name="generator" content="DocBook XSL-NS Stylesheets V1.78.1" /><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="std_contents.html" title="Part II. Standard Contents" /><link rel="prev" href="termination.html" title="Termination" /><link rel="next" href="concept_checking.html" title="Concept Checking" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 5.
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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>Chapter 5. Diagnostics</title><meta name="generator" content="DocBook XSL-NS Stylesheets V1.78.1" /><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="std_contents.html" title="Part II. Standard Contents" /><link rel="prev" href="termination.html" title="Termination" /><link rel="next" href="errno.html" title="Use of errno by the library" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 5.
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Diagnostics
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</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="termination.html">Prev</a> </td><th width="60%" align="center">Part II.
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Standard Contents
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</th><td width="20%" align="right"> <a accesskey="n" href="concept_checking.html">Next</a></td></tr></table><hr /></div><div class="chapter"><div class="titlepage"><div><div><h2 class="title"><a id="std.diagnostics"></a>Chapter 5.
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</th><td width="20%" align="right"> <a accesskey="n" href="errno.html">Next</a></td></tr></table><hr /></div><div class="chapter"><div class="titlepage"><div><div><h2 class="title"><a id="std.diagnostics"></a>Chapter 5.
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Diagnostics
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<a id="id-1.3.4.3.1.1.1" class="indexterm"></a>
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</h2></div></div></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions.api">API Reference</a></span></dt><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions.data">Adding Data to <code class="classname">exception</code></a></span></dt></dl></dd><dt><span class="section"><a href="concept_checking.html">Concept Checking</a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="std.diagnostics.exceptions"></a>Exceptions</h2></div></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="std.diagnostics.exceptions.api"></a>API Reference</h3></div></div></div><p>
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</h2></div></div></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions.api">API Reference</a></span></dt><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions.data">Adding Data to <code class="classname">exception</code></a></span></dt></dl></dd><dt><span class="section"><a href="errno.html">Use of errno by the library</a></span></dt><dt><span class="section"><a href="concept_checking.html">Concept Checking</a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="std.diagnostics.exceptions"></a>Exceptions</h2></div></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="std.diagnostics.exceptions.api"></a>API Reference</h3></div></div></div><p>
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All exception objects are defined in one of the standard header
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files: <code class="filename">exception</code>,
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<code class="filename">stdexcept</code>, <code class="filename">new</code>, and
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@ -39,4 +39,4 @@
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int e;
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DBID id; // some user-defined type
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};
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</pre></div></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="termination.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="std_contents.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="concept_checking.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Termination </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Concept Checking</td></tr></table></div></body></html>
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</pre></div></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="termination.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="std_contents.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="errno.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Termination </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Use of errno by the library</td></tr></table></div></body></html>
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@ -12,7 +12,7 @@
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</a></span></dt><dd><dl><dt><span class="section"><a href="support.html#std.support.types">Types</a></span></dt><dd><dl><dt><span class="section"><a href="support.html#std.support.types.fundamental">Fundamental Types</a></span></dt><dt><span class="section"><a href="support.html#std.support.types.numeric_limits">Numeric Properties</a></span></dt><dt><span class="section"><a href="support.html#std.support.types.null">NULL</a></span></dt></dl></dd><dt><span class="section"><a href="dynamic_memory.html">Dynamic Memory</a></span></dt><dt><span class="section"><a href="termination.html">Termination</a></span></dt><dd><dl><dt><span class="section"><a href="termination.html#support.termination.handlers">Termination Handlers</a></span></dt><dt><span class="section"><a href="termination.html#support.termination.verbose">Verbose Terminate Handler</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="diagnostics.html">5.
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Diagnostics
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</a></span></dt><dd><dl><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions.api">API Reference</a></span></dt><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions.data">Adding Data to <code class="classname">exception</code></a></span></dt></dl></dd><dt><span class="section"><a href="concept_checking.html">Concept Checking</a></span></dt></dl></dd><dt><span class="chapter"><a href="utilities.html">6.
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</a></span></dt><dd><dl><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions.api">API Reference</a></span></dt><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions.data">Adding Data to <code class="classname">exception</code></a></span></dt></dl></dd><dt><span class="section"><a href="errno.html">Use of errno by the library</a></span></dt><dt><span class="section"><a href="concept_checking.html">Concept Checking</a></span></dt></dl></dd><dt><span class="chapter"><a href="utilities.html">6.
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Utilities
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</a></span></dt><dd><dl><dt><span class="section"><a href="utilities.html#std.util.functors">Functors</a></span></dt><dt><span class="section"><a href="pairs.html">Pairs</a></span></dt><dt><span class="section"><a href="memory.html">Memory</a></span></dt><dd><dl><dt><span class="section"><a href="memory.html#std.util.memory.allocator">Allocators</a></span></dt><dd><dl><dt><span class="section"><a href="memory.html#allocator.req">Requirements</a></span></dt><dt><span class="section"><a href="memory.html#allocator.design_issues">Design Issues</a></span></dt><dt><span class="section"><a href="memory.html#allocator.impl">Implementation</a></span></dt><dd><dl><dt><span class="section"><a href="memory.html#allocator.interface">Interface Design</a></span></dt><dt><span class="section"><a href="memory.html#allocator.default">Selecting Default Allocation Policy</a></span></dt><dt><span class="section"><a href="memory.html#allocator.caching">Disabling Memory Caching</a></span></dt></dl></dd><dt><span class="section"><a href="memory.html#allocator.using">Using a Specific Allocator</a></span></dt><dt><span class="section"><a href="memory.html#allocator.custom">Custom Allocators</a></span></dt><dt><span class="section"><a href="memory.html#allocator.ext">Extension Allocators</a></span></dt></dl></dd><dt><span class="section"><a href="memory.html#std.util.memory.auto_ptr">auto_ptr</a></span></dt><dd><dl><dt><span class="section"><a href="memory.html#auto_ptr.limitations">Limitations</a></span></dt><dt><span class="section"><a href="memory.html#auto_ptr.using">Use in Containers</a></span></dt></dl></dd><dt><span class="section"><a href="memory.html#std.util.memory.shared_ptr">shared_ptr</a></span></dt><dd><dl><dt><span class="section"><a href="memory.html#shared_ptr.req">Requirements</a></span></dt><dt><span class="section"><a href="memory.html#shared_ptr.design_issues">Design Issues</a></span></dt><dt><span class="section"><a href="memory.html#shared_ptr.impl">Implementation</a></span></dt><dd><dl><dt><span class="section"><a href="memory.html#shared_ptr.hier">Class Hierarchy</a></span></dt><dt><span class="section"><a href="memory.html#shared_ptr.thread">Thread Safety</a></span></dt><dt><span class="section"><a href="memory.html#shared_ptr.policy">Selecting Lock Policy</a></span></dt><dt><span class="section"><a href="memory.html#shared_ptr.rel">Related functions and classes</a></span></dt></dl></dd><dt><span class="section"><a href="memory.html#shared_ptr.using">Use</a></span></dt><dd><dl><dt><span class="section"><a href="memory.html#shared_ptr.examples">Examples</a></span></dt><dt><span class="section"><a href="memory.html#shared_ptr.issues">Unresolved Issues</a></span></dt></dl></dd><dt><span class="section"><a href="memory.html#shared_ptr.ack">Acknowledgments</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="traits.html">Traits</a></span></dt></dl></dd><dt><span class="chapter"><a href="strings.html">7.
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</a></span></dt><dd><dl><dt><span class="section"><a href="support.html#std.support.types">Types</a></span></dt><dd><dl><dt><span class="section"><a href="support.html#std.support.types.fundamental">Fundamental Types</a></span></dt><dt><span class="section"><a href="support.html#std.support.types.numeric_limits">Numeric Properties</a></span></dt><dt><span class="section"><a href="support.html#std.support.types.null">NULL</a></span></dt></dl></dd><dt><span class="section"><a href="dynamic_memory.html">Dynamic Memory</a></span></dt><dt><span class="section"><a href="termination.html">Termination</a></span></dt><dd><dl><dt><span class="section"><a href="termination.html#support.termination.handlers">Termination Handlers</a></span></dt><dt><span class="section"><a href="termination.html#support.termination.verbose">Verbose Terminate Handler</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="diagnostics.html">5.
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Diagnostics
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</a></span></dt><dd><dl><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions.api">API Reference</a></span></dt><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions.data">Adding Data to <code class="classname">exception</code></a></span></dt></dl></dd><dt><span class="section"><a href="concept_checking.html">Concept Checking</a></span></dt></dl></dd><dt><span class="chapter"><a href="utilities.html">6.
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</a></span></dt><dd><dl><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions.api">API Reference</a></span></dt><dt><span class="section"><a href="diagnostics.html#std.diagnostics.exceptions.data">Adding Data to <code class="classname">exception</code></a></span></dt></dl></dd><dt><span class="section"><a href="errno.html">Use of errno by the library</a></span></dt><dt><span class="section"><a href="concept_checking.html">Concept Checking</a></span></dt></dl></dd><dt><span class="chapter"><a href="utilities.html">6.
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Utilities
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</a></span></dt><dd><dl><dt><span class="section"><a href="utilities.html#std.util.functors">Functors</a></span></dt><dt><span class="section"><a href="pairs.html">Pairs</a></span></dt><dt><span class="section"><a href="memory.html">Memory</a></span></dt><dd><dl><dt><span class="section"><a href="memory.html#std.util.memory.allocator">Allocators</a></span></dt><dd><dl><dt><span class="section"><a href="memory.html#allocator.req">Requirements</a></span></dt><dt><span class="section"><a href="memory.html#allocator.design_issues">Design Issues</a></span></dt><dt><span class="section"><a href="memory.html#allocator.impl">Implementation</a></span></dt><dd><dl><dt><span class="section"><a href="memory.html#allocator.interface">Interface Design</a></span></dt><dt><span class="section"><a href="memory.html#allocator.default">Selecting Default Allocation Policy</a></span></dt><dt><span class="section"><a href="memory.html#allocator.caching">Disabling Memory Caching</a></span></dt></dl></dd><dt><span class="section"><a href="memory.html#allocator.using">Using a Specific Allocator</a></span></dt><dt><span class="section"><a href="memory.html#allocator.custom">Custom Allocators</a></span></dt><dt><span class="section"><a href="memory.html#allocator.ext">Extension Allocators</a></span></dt></dl></dd><dt><span class="section"><a href="memory.html#std.util.memory.auto_ptr">auto_ptr</a></span></dt><dd><dl><dt><span class="section"><a href="memory.html#auto_ptr.limitations">Limitations</a></span></dt><dt><span class="section"><a href="memory.html#auto_ptr.using">Use in Containers</a></span></dt></dl></dd><dt><span class="section"><a href="memory.html#std.util.memory.shared_ptr">shared_ptr</a></span></dt><dd><dl><dt><span class="section"><a href="memory.html#shared_ptr.req">Requirements</a></span></dt><dt><span class="section"><a href="memory.html#shared_ptr.design_issues">Design Issues</a></span></dt><dt><span class="section"><a href="memory.html#shared_ptr.impl">Implementation</a></span></dt><dd><dl><dt><span class="section"><a href="memory.html#shared_ptr.hier">Class Hierarchy</a></span></dt><dt><span class="section"><a href="memory.html#shared_ptr.thread">Thread Safety</a></span></dt><dt><span class="section"><a href="memory.html#shared_ptr.policy">Selecting Lock Policy</a></span></dt><dt><span class="section"><a href="memory.html#shared_ptr.rel">Related functions and classes</a></span></dt></dl></dd><dt><span class="section"><a href="memory.html#shared_ptr.using">Use</a></span></dt><dd><dl><dt><span class="section"><a href="memory.html#shared_ptr.examples">Examples</a></span></dt><dt><span class="section"><a href="memory.html#shared_ptr.issues">Unresolved Issues</a></span></dt></dl></dd><dt><span class="section"><a href="memory.html#shared_ptr.ack">Acknowledgments</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="traits.html">Traits</a></span></dt></dl></dd><dt><span class="chapter"><a href="strings.html">7.
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</section>
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</section>
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<section xml:id="std.diagnostics.errno" xreflabel="errno"><info><title>Use of errno by the library</title></info>
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<?dbhtml filename="errno.html"?>
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||||
<para>
|
||||
The C and POSIX standards guarantee that <varname>errno</varname>
|
||||
is never set to zero by any library function.
|
||||
The C++ standard has less to say about when <varname>errno</varname>
|
||||
is or isn't set, but libstdc++ follows the same rule and never sets
|
||||
it to zero.
|
||||
</para>
|
||||
|
||||
<para>
|
||||
On the other hand, there are few guarantees about when the C++ library
|
||||
sets <varname>errno</varname> on error, beyond what is specified for
|
||||
functions that come from the C library.
|
||||
For example, when <function>std::stoi</function> throws an exception of
|
||||
type <classname>std::out_of_range</classname>, <varname>errno</varname>
|
||||
may or may not have been set to <constant>ERANGE</constant>.
|
||||
</para>
|
||||
|
||||
<para>
|
||||
Parts of the C++ library may be implemented in terms of C library
|
||||
functions, which may result in <varname>errno</varname> being set
|
||||
with no explicit call to a C function. For example, on a target where
|
||||
<function>operator new</function> uses <function>malloc</function>
|
||||
a failed memory allocation with <function>operator new</function> might
|
||||
set <varname>errno</varname> to <constant>ENOMEM</constant>.
|
||||
Which C++ library functions can set <varname>errno</varname> in this way
|
||||
is unspecified because it may vary between platforms and between releases.
|
||||
</para>
|
||||
|
||||
</section>
|
||||
|
||||
<section xml:id="std.diagnostics.concept_checking" xreflabel="Concept Checking"><info><title>Concept Checking</title></info>
|
||||
<?dbhtml filename="concept_checking.html"?>
|
||||
|
||||
|
|
|
|||
|
|
@ -58,8 +58,13 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
|
|||
_Ret __ret;
|
||||
|
||||
_CharT* __endptr;
|
||||
const int __saved_errno = errno;
|
||||
errno = 0;
|
||||
|
||||
struct _Save_errno {
|
||||
_Save_errno() : _M_errno(errno) { errno = 0; }
|
||||
~_Save_errno() { if (errno == 0) errno = _M_errno; }
|
||||
int _M_errno;
|
||||
} const __save_errno;
|
||||
|
||||
const _TRet __tmp = __convf(__str, &__endptr, __base...);
|
||||
|
||||
if (__endptr == __str)
|
||||
|
|
@ -71,7 +76,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
|
|||
std::__throw_out_of_range(__name);
|
||||
else
|
||||
__ret = __tmp;
|
||||
errno = __saved_errno;
|
||||
|
||||
if (__idx)
|
||||
*__idx = __endptr - __str;
|
||||
|
|
|
|||
Loading…
Reference in New Issue