* doc/xml/manual/status_cxx2017.xml: Document P0024R2 status.
* doc/html/*: Regenerate.
From-SVN: r270559
2019-04-24 Jonathan Wakely <jwakely@redhat.com>
+ * doc/xml/manual/status_cxx2017.xml: Document P0024R2 status.
+ * doc/html/*: Regenerate.
+
* include/bits/fs_path.h (operator<, operator<=, operator>)
(operator>=, operator==, operator!=): Make hidden friends, as per
LWG 3065.
Program crashes when using library code in a
dynamically-loaded library
</a></dt><dt>6.7. <a href="faq.html#faq.memory_leaks">
- “Memory leaks” in containers
+ “Memory leaks” in libstdc++
</a></dt><dt>6.8. <a href="faq.html#faq.list_size_on">
list::size() is O(n)!
</a></dt><dt>6.9. <a href="faq.html#faq.easy_to_fix">
Program crashes when using library code in a
dynamically-loaded library
</a></dt><dt>6.7. <a href="faq.html#faq.memory_leaks">
- “Memory leaks” in containers
+ “Memory leaks” in libstdc++
</a></dt><dt>6.8. <a href="faq.html#faq.list_size_on">
list::size() is O(n)!
</a></dt><dt>6.9. <a href="faq.html#faq.easy_to_fix">
Link the executable:<br />
<span class="command"><strong>g++ -fPIC -rdynamic -o foo ... -L. -lfoo -ldl</strong></span><br />
</p></div></td></tr><tr class="question"><td align="left" valign="top"><a id="faq.memory_leaks"></a><a id="q-memory_leaks"></a><p><strong>6.7.</strong></p></td><td align="left" valign="top"><p>
- <span class="quote">“<span class="quote">Memory leaks</span>”</span> in containers
- </p></td></tr><tr class="answer"><td align="left" valign="top"><a id="a-memory_leaks"></a></td><td align="left" valign="top"><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>This answer is old and probably no longer be relevant.</p></div><p>
- A few people have reported that the standard containers appear
+ <span class="quote">“<span class="quote">Memory leaks</span>”</span> in libstdc++
+ </p></td></tr><tr class="answer"><td align="left" valign="top"><a id="a-memory_leaks"></a></td><td align="left" valign="top"><p>
+ Since GCC 5.1.0, libstdc++ automatically allocates a pool
+ of a few dozen kilobytes on startup. This pool is used to ensure it's
+ possible to throw exceptions (such as <code class="classname">bad_alloc</code>)
+ even when <code class="code">malloc</code> is unable to allocate any more memory.
+ With some versions of <a class="link" href="http://valgrind.org/" target="_top"><span class="command"><strong>valgrind</strong></span></a>
+ this pool will be shown as "still reachable" when the process exits, e.g.
+ <code class="code">still reachable: 72,704 bytes in 1 blocks</code>.
+ This memory is not a leak, because it's still in use by libstdc++,
+ and the memory will be returned to the OS when the process exits.
+ Later versions of <span class="command"><strong>valgrind</strong></span> know how to free this
+ pool as the process exits, and so won't show any "still reachable" memory.
+ </p><p>
+ In the past, a few people reported that the standard containers appear
to leak memory when tested with memory checkers such as
<a class="link" href="http://valgrind.org/" target="_top"><span class="command"><strong>valgrind</strong></span></a>.
Under some (non-default) configurations the library's allocators keep
free memory in a
- pool for later reuse, rather than returning it to the OS. Although
- this memory is always reachable by the library and is never
+ pool for later reuse, rather than deallocating it with <code class="code">delete</code>
+ Although this memory is always reachable by the library and is never
lost, memory debugging tools can report it as a leak. If you
want to test the library for memory leaks please read
<a class="link" href="manual/debug.html#debug.memory" title="Memory Leak Hunting">Tips for memory leak hunting</a>
</p></div></div></div><hr /></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="book"><a href="manual/index.html">The GNU C++ Library Manual</a></span></dt><dd><dl><dt><span class="part"><a href="manual/intro.html">I.
Introduction
-</a></span></dt><dd><dl><dt><span class="chapter"><a href="manual/status.html">1. Status</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#manual.intro.status.iso">Implementation Status</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#status.iso.1998">C++ 1998/2003</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.1998.status">Implementation Status</a></span></dt><dt><span class="section"><a href="manual/status.html#iso.1998.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.2011">C++ 2011</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.2011.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.2014">C++ 2014</a></span></dt><dt><span class="section"><a href="manual/status.html#status.iso.2017">C++ 2017</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.2017.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.2020">C++ 202a</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.2020.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.tr1">C++ TR1</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.tr1.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.tr24733">C++ TR 24733</a></span></dt><dt><span class="section"><a href="manual/status.html#status.iso.specfun">C++ IS 29124</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.specfun.specific">Implementation Specific Behavior</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="manual/license.html">License</a></span></dt><dd><dl><dt><span class="section"><a href="manual/license.html#manual.intro.status.license.gpl">The Code: GPL</a></span></dt><dt><span class="section"><a href="manual/license.html#manual.intro.status.license.fdl">The Documentation: GPL, FDL</a></span></dt></dl></dd><dt><span class="section"><a href="manual/bugs.html">Bugs</a></span></dt><dd><dl><dt><span class="section"><a href="manual/bugs.html#manual.intro.status.bugs.impl">Implementation Bugs</a></span></dt><dt><span class="section"><a href="manual/bugs.html#manual.intro.status.bugs.iso">Standard Bugs</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="manual/setup.html">2. Setup</a></span></dt><dd><dl><dt><span class="section"><a href="manual/setup.html#manual.intro.setup.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="manual/configure.html">Configure</a></span></dt><dt><span class="section"><a href="manual/make.html">Make</a></span></dt></dl></dd><dt><span class="chapter"><a href="manual/using.html">3. Using</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using.html#manual.intro.using.flags">Command Options</a></span></dt><dt><span class="section"><a href="manual/using_headers.html">Headers</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_headers.html#manual.intro.using.headers.all">Header Files</a></span></dt><dt><span class="section"><a href="manual/using_headers.html#manual.intro.using.headers.mixing">Mixing Headers</a></span></dt><dt><span class="section"><a href="manual/using_headers.html#manual.intro.using.headers.cheaders">The C Headers and <code class="code">namespace std</code></a></span></dt><dt><span class="section"><a href="manual/using_headers.html#manual.intro.using.headers.pre">Precompiled Headers</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_macros.html">Macros</a></span></dt><dt><span class="section"><a href="manual/using_dual_abi.html">Dual ABI</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_dual_abi.html#manual.intro.using.abi.trouble">Troubleshooting</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_namespaces.html">Namespaces</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_namespaces.html#manual.intro.using.namespaces.all">Available Namespaces</a></span></dt><dt><span class="section"><a href="manual/using_namespaces.html#manual.intro.using.namespaces.std">namespace std</a></span></dt><dt><span class="section"><a href="manual/using_namespaces.html#manual.intro.using.namespaces.comp">Using Namespace Composition</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_dynamic_or_shared.html">Linking</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_dynamic_or_shared.html#manual.intro.using.linkage.freestanding">Almost Nothing</a></span></dt><dt><span class="section"><a href="manual/using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic">Finding Dynamic or Shared Libraries</a></span></dt><dt><span class="section"><a href="manual/using_dynamic_or_shared.html#manual.intro.using.linkage.experimental">Experimental Library Extensions</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_concurrency.html">Concurrency</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.thread_safety">Thread Safety</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.atomics">Atomics</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.io">IO</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_concurrency.html#concurrency.io.structure">Structure</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#concurrency.io.defaults">Defaults</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#concurrency.io.future">Future</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#concurrency.io.alt">Alternatives</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.containers">Containers</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_exceptions.html">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.safety">Exception Safety</a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.propagating">Exception Neutrality</a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.no">Doing without</a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.compat">Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_exceptions.html#using.exception.compat.c">With <code class="literal">C</code></a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#using.exception.compat.posix">With <code class="literal">POSIX</code> thread cancellation</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="manual/debug.html">Debugging Support</a></span></dt><dd><dl><dt><span class="section"><a href="manual/debug.html#debug.compiler">Using <span class="command"><strong>g++</strong></span></a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.req">Debug Versions of Library Binary Files</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.memory">Memory Leak Hunting</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.races">Data Race Hunting</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.gdb">Using <span class="command"><strong>gdb</strong></span></a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.exceptions">Tracking uncaught exceptions</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.debug_mode">Debug Mode</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.compile_time_checks">Compile Time Checking</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.profile_mode">Profile-based Performance Analysis</a></span></dt></dl></dd></dl></dd></dl></dd><dt><span class="part"><a href="manual/std_contents.html">II.
+</a></span></dt><dd><dl><dt><span class="chapter"><a href="manual/status.html">1. Status</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#manual.intro.status.iso">Implementation Status</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#status.iso.1998">C++ 1998/2003</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.1998.status">Implementation Status</a></span></dt><dt><span class="section"><a href="manual/status.html#iso.1998.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.2011">C++ 2011</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.2011.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.2014">C++ 2014</a></span></dt><dt><span class="section"><a href="manual/status.html#status.iso.2017">C++ 2017</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.2017.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.2020">C++ 202a</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.2020.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.tr1">C++ TR1</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.tr1.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.tr24733">C++ TR 24733</a></span></dt><dt><span class="section"><a href="manual/status.html#status.iso.specfun">C++ IS 29124</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.specfun.specific">Implementation Specific Behavior</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="manual/license.html">License</a></span></dt><dd><dl><dt><span class="section"><a href="manual/license.html#manual.intro.status.license.gpl">The Code: GPL</a></span></dt><dt><span class="section"><a href="manual/license.html#manual.intro.status.license.fdl">The Documentation: GPL, FDL</a></span></dt></dl></dd><dt><span class="section"><a href="manual/bugs.html">Bugs</a></span></dt><dd><dl><dt><span class="section"><a href="manual/bugs.html#manual.intro.status.bugs.impl">Implementation Bugs</a></span></dt><dt><span class="section"><a href="manual/bugs.html#manual.intro.status.bugs.iso">Standard Bugs</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="manual/setup.html">2. Setup</a></span></dt><dd><dl><dt><span class="section"><a href="manual/setup.html#manual.intro.setup.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="manual/configure.html">Configure</a></span></dt><dt><span class="section"><a href="manual/make.html">Make</a></span></dt></dl></dd><dt><span class="chapter"><a href="manual/using.html">3. Using</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using.html#manual.intro.using.flags">Command Options</a></span></dt><dt><span class="section"><a href="manual/using_headers.html">Headers</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_headers.html#manual.intro.using.headers.all">Header Files</a></span></dt><dt><span class="section"><a href="manual/using_headers.html#manual.intro.using.headers.mixing">Mixing Headers</a></span></dt><dt><span class="section"><a href="manual/using_headers.html#manual.intro.using.headers.cheaders">The C Headers and <code class="code">namespace std</code></a></span></dt><dt><span class="section"><a href="manual/using_headers.html#manual.intro.using.headers.pre">Precompiled Headers</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_macros.html">Macros</a></span></dt><dt><span class="section"><a href="manual/using_dual_abi.html">Dual ABI</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_dual_abi.html#manual.intro.using.abi.trouble">Troubleshooting</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_namespaces.html">Namespaces</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_namespaces.html#manual.intro.using.namespaces.all">Available Namespaces</a></span></dt><dt><span class="section"><a href="manual/using_namespaces.html#manual.intro.using.namespaces.std">namespace std</a></span></dt><dt><span class="section"><a href="manual/using_namespaces.html#manual.intro.using.namespaces.comp">Using Namespace Composition</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_dynamic_or_shared.html">Linking</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_dynamic_or_shared.html#manual.intro.using.linkage.freestanding">Almost Nothing</a></span></dt><dt><span class="section"><a href="manual/using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic">Finding Dynamic or Shared Libraries</a></span></dt><dt><span class="section"><a href="manual/using_dynamic_or_shared.html#manual.intro.using.linkage.experimental">Experimental Library Extensions</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_concurrency.html">Concurrency</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.thread_safety">Thread Safety</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.atomics">Atomics</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.io">IO</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_concurrency.html#concurrency.io.structure">Structure</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#concurrency.io.defaults">Defaults</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#concurrency.io.future">Future</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#concurrency.io.alt">Alternatives</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.containers">Containers</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_exceptions.html">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.safety">Exception Safety</a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.propagating">Exception Neutrality</a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.no">Doing without</a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.compat">Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_exceptions.html#using.exception.compat.c">With <code class="literal">C</code></a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#using.exception.compat.posix">With <code class="literal">POSIX</code> thread cancellation</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="manual/debug.html">Debugging Support</a></span></dt><dd><dl><dt><span class="section"><a href="manual/debug.html#debug.compiler">Using <span class="command"><strong>g++</strong></span></a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.req">Debug Versions of Library Binary Files</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.memory">Memory Leak Hunting</a></span></dt><d
d><dl><dt><span class="section"><a href="manual/debug.html#debug.memory.mtalloc">Non-memory leaks in Pool and MT allocators</a></span></dt></dl></dd><dt><span class="section"><a href="manual/debug.html#debug.races">Data Race Hunting</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.gdb">Using <span class="command"><strong>gdb</strong></span></a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.exceptions">Tracking uncaught exceptions</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.debug_mode">Debug Mode</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.compile_time_checks">Compile Time Checking</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.profile_mode">Profile-based Performance Analysis</a></span></dt></dl></dd></dl></dd></dl></dd><dt><span class="part"><a href="manual/std_contents.html">II.
Standard Contents
</a></span></dt><dd><dl><dt><span class="chapter"><a href="manual/support.html">4.
Support
</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="api.rel_320"></a><code class="constant">3.2</code></h3></div></div></div><p>
</p><p>Symbol versioning introduced for shared library.</p><p>Removal of include <code class="filename"><backward/strstream.h></code>.</p><p>Allocator changes. Change <code class="code">__malloc_alloc</code> to <code class="code">malloc_allocator</code> and <code class="code">__new_alloc</code> to <code class="code">new_allocator</code>. </p><p> For GCC releases from 2.95 through the 3.1 series, defining
<code class="literal">__USE_MALLOC</code> on the gcc command line would change the
- default allocation strategy to instead use <code class="code"> malloc</code> and
- <code class="function">free</code>. For the 3.2 and 3.3 release series the same
+ default allocation strategy to instead use <code class="code">malloc</code> and
+ <code class="code">free</code>. For the 3.2 and 3.3 release series the same
functionality was spelled <code class="literal">_GLIBCXX_FORCE_NEW</code>. From
- GCC 3.4 onwards the functionality is enabled by setting
- <code class="literal">GLIBCXX_FORCE_NEW</code> in the environment, see
+ GCC 3.4 onwards the default allocator uses <code class="code">new</code> anyway,
+ but for the optional pooling allocators the functionality is enabled by
+ setting <code class="literal">GLIBCXX_FORCE_NEW</code> in the environment, see
<a class="link" href="mt_allocator.html" title="Chapter 20. The mt_allocator">the mt allocator chapter</a>
for details.
</p><p>Error handling in iostreams cleaned up, made consistent. </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="api.rel_330"></a><code class="constant">3.3</code></h3></div></div></div><p>
stream-constructor.
</p><p>
An extension is available that implements this.
- <code class="filename"><ext/stdio_filebuf.h></code> contains a derived class called
- <a class="link" href="http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/a00074.html" target="_top"><code class="code">__gnu_cxx::stdio_filebuf</code></a>.
+ <code class="filename"><ext/stdio_filebuf.h></code>
+ contains a derived class called
+ <code class="classname">__gnu_cxx::stdio_filebuf</code>.
This class can be constructed from a C <code class="code">FILE*</code> or a file
descriptor, and provides the <code class="code">fd()</code> function.
</p><p>
This quick and dirty approach is often sufficient for quick
debugging tasks, when you cannot or don't want to recompile your
application to use the <a class="link" href="debug_mode.html" title="Chapter 17. Debug Mode">debug mode</a>.</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="debug.memory"></a>Memory Leak Hunting</h3></div></div></div><p>
- There are various third party memory tracing and debug utilities
+ On many targets GCC supports AddressSanitizer, a fast memory error detector,
+ which is enabled by the <code class="option">-fsanitize=address</code> option.
+</p><p>
+ There are also various third party memory tracing and debug utilities
that can be used to provide detailed memory allocation information
about C++ code. An exhaustive list of tools is not going to be
attempted, but includes <code class="code">mtrace</code>, <code class="code">valgrind</code>,
- <code class="code">mudflap</code>, and the non-free commercial product
- <code class="code">purify</code>. In addition, <code class="code">libcwd</code> has a
- replacement for the global new and delete operators that can track
- memory allocation and deallocation and provide useful memory
- statistics.
-</p><p>
- Regardless of the memory debugging tool being used, there is one
- thing of great importance to keep in mind when debugging C++ code
- that uses <code class="code">new</code> and <code class="code">delete</code>: there are
- different kinds of allocation schemes that can be used by <code class="code">
- std::allocator</code>. For implementation details, see the <a class="link" href="mt_allocator.html" title="Chapter 20. The mt_allocator">mt allocator</a> documentation and
- look specifically for <code class="code">GLIBCXX_FORCE_NEW</code>.
-</p><p>
- In a nutshell, the optional <code class="classname">mt_allocator</code>
- is a high-performance pool allocator, and can
- give the mistaken impression that in a suspect executable, memory is
- being leaked, when in reality the memory "leak" is a pool being used
- by the library's allocator and is reclaimed after program
- termination.
+ <code class="code">mudflap</code> (no longer supported since GCC 4.9.0), ElectricFence,
+ and the non-free commercial product <code class="code">purify</code>.
+ In addition, <code class="code">libcwd</code>, jemalloc and TCMalloc have replacements
+ for the global <code class="code">new</code> and <code class="code">delete</code> operators
+ that can track memory allocation and deallocation and provide useful
+ memory statistics.
</p><p>
For valgrind, there are some specific items to keep in mind. First
of all, use a version of valgrind that will work with current GNU
C++ tools: the first that can do this is valgrind 1.0.4, but later
- versions should work at least as well. Second of all, use a
- completely unoptimized build to avoid confusing valgrind. Third, use
- GLIBCXX_FORCE_NEW to keep extraneous pool allocation noise from
- cluttering debug information.
+ versions should work better. Second, using an unoptimized build
+ might avoid confusing valgrind.
</p><p>
- Fourth, it may be necessary to force deallocation in other libraries
- as well, namely the "C" library. On linux, this can be accomplished
+ Third, it may be necessary to force deallocation in other libraries
+ as well, namely the "C" library. On GNU/Linux, this can be accomplished
with the appropriate use of the <code class="code">__cxa_atexit</code> or
<code class="code">atexit</code> functions.
</p><pre class="programlisting">
up the runtime environment, library, and test file, might be:
</p><pre class="programlisting">
valgrind -v --num-callers=20 --leak-check=yes --leak-resolution=high --show-reachable=yes a.out
-</pre></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="debug.races"></a>Data Race Hunting</h3></div></div></div><p>
+</pre><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="debug.memory.mtalloc"></a>Non-memory leaks in Pool and MT allocators</h4></div></div></div><p>
+ There are different kinds of allocation schemes that can be used by
+ <code class="code">std::allocator</code>. Prior to GCC 3.4.0 the default was to use
+ a pooling allocator, <code class="classname">pool_allocator</code>,
+ which is still available as the optional
+ <code class="classname">__pool_alloc</code> extension.
+ Another optional extension, <code class="classname">__mt_alloc</code>,
+ is a high-performance pool allocator.
+</p><p>
+ In a suspect executable these pooling allocators can give
+ the mistaken impression that memory is being leaked,
+ when in reality the memory "leak" is a pool being used
+ by the library's allocator and is reclaimed after program
+ termination.
+</p><p>
+ If you're using memory debugging tools on a program that uses
+ one of these pooling allocators, you can set the environment variable
+ <code class="literal">GLIBCXX_FORCE_NEW</code> to keep extraneous pool allocation
+ noise from cluttering debug information.
+ For more details, see the
+ <a class="link" href="mt_allocator.html" title="Chapter 20. The mt_allocator">mt allocator</a>
+ documentation and look specifically for <code class="code">GLIBCXX_FORCE_NEW</code>.
+</p></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="debug.races"></a>Data Race Hunting</h3></div></div></div><p>
All synchronization primitives used in the library internals need to be
understood by race detectors so that they do not produce false reports.
</p><p>
the current host. In libstdc++ implementation files,
<bits/gthr.h> is used to select the proper gthreads file.
</p><p>Within libstdc++ sources, all calls to underlying thread functionality
-use this layer. More detail as to the specific interface can be found in the source <a class="link" href="http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/a00883_source.html" target="_top">documentation</a>.
+use this layer. More detail as to the specific interface can be found in the source <a class="link" href="http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/index.html" target="_top">documentation</a>.
</p><p>By design, the gthread layer is interoperable with the types,
functions, and usage found in the usual <pthread.h> file,
including <code class="code">pthread_t</code>, <code class="code">pthread_once_t</code>, <code class="code">pthread_create</code>,
library cannot track what you do on your own with a file descriptor,
so if you perform any I/O directly, don't expect the library to be
aware of it.
- </p></li><li class="listitem"><p>Beginning with 3.1, the extra <code class="code">filebuf</code> constructor and
+ </p></li><li class="listitem"><p>Beginning with 3.1, the extra
+ <code class="classname">basic_filebuf</code> constructor and
the <code class="code">fd()</code> function were removed from the standard
- filebuf. Instead, <code class="code"><ext/stdio_filebuf.h></code> contains
- a derived class called
- <a class="link" href="http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/a00074.html" target="_top"><code class="code">__gnu_cxx::stdio_filebuf</code></a>.
+ filebuf. Instead,
+ <code class="filename"><ext/stdio_filebuf.h></code>
+ contains a derived class template called
+ <code class="classname">__gnu_cxx::stdio_filebuf</code>.
This class can be constructed from a C <code class="code">FILE*</code> or a file
descriptor, and provides the <code class="code">fd()</code> function.
</p></li></ul></div></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ext_iterators.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="extensions.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="ext_demangling.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 27. Iterators </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 29. Demangling</td></tr></table></div></body></html>
\ No newline at end of file
</p></div></div><hr /></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="part"><a href="intro.html">I.
Introduction
-</a></span></dt><dd><dl><dt><span class="chapter"><a href="status.html">1. Status</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#manual.intro.status.iso">Implementation Status</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#status.iso.1998">C++ 1998/2003</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.1998.status">Implementation Status</a></span></dt><dt><span class="section"><a href="status.html#iso.1998.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2011">C++ 2011</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2011.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2014">C++ 2014</a></span></dt><dt><span class="section"><a href="status.html#status.iso.2017">C++ 2017</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2017.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2020">C++ 202a</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2020.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.tr1">C++ TR1</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.tr1.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.tr24733">C++ TR 24733</a></span></dt><dt><span class="section"><a href="status.html#status.iso.specfun">C++ IS 29124</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.specfun.specific">Implementation Specific Behavior</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="license.html">License</a></span></dt><dd><dl><dt><span class="section"><a href="license.html#manual.intro.status.license.gpl">The Code: GPL</a></span></dt><dt><span class="section"><a href="license.html#manual.intro.status.license.fdl">The Documentation: GPL, FDL</a></span></dt></dl></dd><dt><span class="section"><a href="bugs.html">Bugs</a></span></dt><dd><dl><dt><span class="section"><a href="bugs.html#manual.intro.status.bugs.impl">Implementation Bugs</a></span></dt><dt><span class="section"><a href="bugs.html#manual.intro.status.bugs.iso">Standard Bugs</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="setup.html">2. Setup</a></span></dt><dd><dl><dt><span class="section"><a href="setup.html#manual.intro.setup.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="configure.html">Configure</a></span></dt><dt><span class="section"><a href="make.html">Make</a></span></dt></dl></dd><dt><span class="chapter"><a href="using.html">3. Using</a></span></dt><dd><dl><dt><span class="section"><a href="using.html#manual.intro.using.flags">Command Options</a></span></dt><dt><span class="section"><a href="using_headers.html">Headers</a></span></dt><dd><dl><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.all">Header Files</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.mixing">Mixing Headers</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.cheaders">The C Headers and <code class="code">namespace std</code></a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.pre">Precompiled Headers</a></span></dt></dl></dd><dt><span class="section"><a href="using_macros.html">Macros</a></span></dt><dt><span class="section"><a href="using_dual_abi.html">Dual ABI</a></span></dt><dd><dl><dt><span class="section"><a href="using_dual_abi.html#manual.intro.using.abi.trouble">Troubleshooting</a></span></dt></dl></dd><dt><span class="section"><a href="using_namespaces.html">Namespaces</a></span></dt><dd><dl><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.all">Available Namespaces</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.std">namespace std</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.comp">Using Namespace Composition</a></span></dt></dl></dd><dt><span class="section"><a href="using_dynamic_or_shared.html">Linking</a></span></dt><dd><dl><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.freestanding">Almost Nothing</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic">Finding Dynamic or Shared Libraries</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.experimental">Experimental Library Extensions</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html">Concurrency</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.thread_safety">Thread Safety</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.atomics">Atomics</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.io">IO</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#concurrency.io.structure">Structure</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.defaults">Defaults</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.future">Future</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.alt">Alternatives</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.containers">Containers</a></span></dt></dl></dd><dt><span class="section"><a href="using_exceptions.html">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.safety">Exception Safety</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.propagating">Exception Neutrality</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.no">Doing without</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.compat">Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.c">With <code class="literal">C</code></a></span></dt><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.posix">With <code class="literal">POSIX</code> thread cancellation</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="debug.html">Debugging Support</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.compiler">Using <span class="command"><strong>g++</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.req">Debug Versions of Library Binary Files</a></span></dt><dt><span class="section"><a href="debug.html#debug.memory">Memory Leak Hunting</a></span></dt><dt><span class="section"><a href="debug.html#debug.races">Data Race Hunting</a></span></dt><dt><span class="section"><a href="debug.html#debug.gdb">Using <span class="command"><strong>gdb</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.exceptions">Tracking uncaught exceptions</a></span></dt><dt><span class="section"><a href="debug.html#debug.debug_mode">Debug Mode</a></span></dt><dt><span class="section"><a href="debug.html#debug.compile_time_checks">Compile Time Checking</a></span></dt><dt><span class="section"><a href="debug.html#debug.profile_mode">Profile-based Performance Analysis</a></span></dt></dl></dd></dl></dd></dl></dd><dt><span class="part"><a href="std_contents.html">II.
+</a></span></dt><dd><dl><dt><span class="chapter"><a href="status.html">1. Status</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#manual.intro.status.iso">Implementation Status</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#status.iso.1998">C++ 1998/2003</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.1998.status">Implementation Status</a></span></dt><dt><span class="section"><a href="status.html#iso.1998.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2011">C++ 2011</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2011.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2014">C++ 2014</a></span></dt><dt><span class="section"><a href="status.html#status.iso.2017">C++ 2017</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2017.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2020">C++ 202a</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2020.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.tr1">C++ TR1</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.tr1.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.tr24733">C++ TR 24733</a></span></dt><dt><span class="section"><a href="status.html#status.iso.specfun">C++ IS 29124</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.specfun.specific">Implementation Specific Behavior</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="license.html">License</a></span></dt><dd><dl><dt><span class="section"><a href="license.html#manual.intro.status.license.gpl">The Code: GPL</a></span></dt><dt><span class="section"><a href="license.html#manual.intro.status.license.fdl">The Documentation: GPL, FDL</a></span></dt></dl></dd><dt><span class="section"><a href="bugs.html">Bugs</a></span></dt><dd><dl><dt><span class="section"><a href="bugs.html#manual.intro.status.bugs.impl">Implementation Bugs</a></span></dt><dt><span class="section"><a href="bugs.html#manual.intro.status.bugs.iso">Standard Bugs</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="setup.html">2. Setup</a></span></dt><dd><dl><dt><span class="section"><a href="setup.html#manual.intro.setup.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="configure.html">Configure</a></span></dt><dt><span class="section"><a href="make.html">Make</a></span></dt></dl></dd><dt><span class="chapter"><a href="using.html">3. Using</a></span></dt><dd><dl><dt><span class="section"><a href="using.html#manual.intro.using.flags">Command Options</a></span></dt><dt><span class="section"><a href="using_headers.html">Headers</a></span></dt><dd><dl><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.all">Header Files</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.mixing">Mixing Headers</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.cheaders">The C Headers and <code class="code">namespace std</code></a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.pre">Precompiled Headers</a></span></dt></dl></dd><dt><span class="section"><a href="using_macros.html">Macros</a></span></dt><dt><span class="section"><a href="using_dual_abi.html">Dual ABI</a></span></dt><dd><dl><dt><span class="section"><a href="using_dual_abi.html#manual.intro.using.abi.trouble">Troubleshooting</a></span></dt></dl></dd><dt><span class="section"><a href="using_namespaces.html">Namespaces</a></span></dt><dd><dl><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.all">Available Namespaces</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.std">namespace std</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.comp">Using Namespace Composition</a></span></dt></dl></dd><dt><span class="section"><a href="using_dynamic_or_shared.html">Linking</a></span></dt><dd><dl><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.freestanding">Almost Nothing</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic">Finding Dynamic or Shared Libraries</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.experimental">Experimental Library Extensions</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html">Concurrency</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.thread_safety">Thread Safety</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.atomics">Atomics</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.io">IO</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#concurrency.io.structure">Structure</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.defaults">Defaults</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.future">Future</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.alt">Alternatives</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.containers">Containers</a></span></dt></dl></dd><dt><span class="section"><a href="using_exceptions.html">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.safety">Exception Safety</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.propagating">Exception Neutrality</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.no">Doing without</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.compat">Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.c">With <code class="literal">C</code></a></span></dt><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.posix">With <code class="literal">POSIX</code> thread cancellation</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="debug.html">Debugging Support</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.compiler">Using <span class="command"><strong>g++</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.req">Debug Versions of Library Binary Files</a></span></dt><dt><span class="section"><a href="debug.html#debug.memory">Memory Leak Hunting</a></span></dt><d
d><dl><dt><span class="section"><a href="debug.html#debug.memory.mtalloc">Non-memory leaks in Pool and MT allocators</a></span></dt></dl></dd><dt><span class="section"><a href="debug.html#debug.races">Data Race Hunting</a></span></dt><dt><span class="section"><a href="debug.html#debug.gdb">Using <span class="command"><strong>gdb</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.exceptions">Tracking uncaught exceptions</a></span></dt><dt><span class="section"><a href="debug.html#debug.debug_mode">Debug Mode</a></span></dt><dt><span class="section"><a href="debug.html#debug.compile_time_checks">Compile Time Checking</a></span></dt><dt><span class="section"><a href="debug.html#debug.profile_mode">Profile-based Performance Analysis</a></span></dt></dl></dd></dl></dd></dl></dd><dt><span class="part"><a href="std_contents.html">II.
Standard Contents
</a></span></dt><dd><dl><dt><span class="chapter"><a href="support.html">4.
Support
</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="index.html">Prev</a> </td><th width="60%" align="center">The GNU C++ Library Manual</th><td width="20%" align="right"> <a accesskey="n" href="status.html">Next</a></td></tr></table><hr /></div><div class="part"><div class="titlepage"><div><div><h1 class="title"><a id="manual.intro"></a>Part I.
Introduction
<a id="id-1.3.3.1.1.1" class="indexterm"></a>
-</h1></div></div></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="chapter"><a href="status.html">1. Status</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#manual.intro.status.iso">Implementation Status</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#status.iso.1998">C++ 1998/2003</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.1998.status">Implementation Status</a></span></dt><dt><span class="section"><a href="status.html#iso.1998.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2011">C++ 2011</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2011.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2014">C++ 2014</a></span></dt><dt><span class="section"><a href="status.html#status.iso.2017">C++ 2017</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2017.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2020">C++ 202a</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2020.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.tr1">C++ TR1</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.tr1.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.tr24733">C++ TR 24733</a></span></dt><dt><span class="section"><a href="status.html#status.iso.specfun">C++ IS 29124</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.specfun.specific">Implementation Specific Behavior</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="license.html">License</a></span></dt><dd><dl><dt><span class="section"><a href="license.html#manual.intro.status.license.gpl">The Code: GPL</a></span></dt><dt><span class="section"><a href="license.html#manual.intro.status.license.fdl">The Documentation: GPL, FDL</a></span></dt></dl></dd><dt><span class="section"><a href="bugs.html">Bugs</a></span></dt><dd><dl><dt><span class="section"><a href="bugs.html#manual.intro.status.bugs.impl">Implementation Bugs</a></span></dt><dt><span class="section"><a href="bugs.html#manual.intro.status.bugs.iso">Standard Bugs</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="setup.html">2. Setup</a></span></dt><dd><dl><dt><span class="section"><a href="setup.html#manual.intro.setup.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="configure.html">Configure</a></span></dt><dt><span class="section"><a href="make.html">Make</a></span></dt></dl></dd><dt><span class="chapter"><a href="using.html">3. Using</a></span></dt><dd><dl><dt><span class="section"><a href="using.html#manual.intro.using.flags">Command Options</a></span></dt><dt><span class="section"><a href="using_headers.html">Headers</a></span></dt><dd><dl><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.all">Header Files</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.mixing">Mixing Headers</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.cheaders">The C Headers and <code class="code">namespace std</code></a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.pre">Precompiled Headers</a></span></dt></dl></dd><dt><span class="section"><a href="using_macros.html">Macros</a></span></dt><dt><span class="section"><a href="using_dual_abi.html">Dual ABI</a></span></dt><dd><dl><dt><span class="section"><a href="using_dual_abi.html#manual.intro.using.abi.trouble">Troubleshooting</a></span></dt></dl></dd><dt><span class="section"><a href="using_namespaces.html">Namespaces</a></span></dt><dd><dl><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.all">Available Namespaces</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.std">namespace std</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.comp">Using Namespace Composition</a></span></dt></dl></dd><dt><span class="section"><a href="using_dynamic_or_shared.html">Linking</a></span></dt><dd><dl><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.freestanding">Almost Nothing</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic">Finding Dynamic or Shared Libraries</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.experimental">Experimental Library Extensions</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html">Concurrency</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.thread_safety">Thread Safety</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.atomics">Atomics</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.io">IO</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#concurrency.io.structure">Structure</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.defaults">Defaults</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.future">Future</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.alt">Alternatives</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.containers">Containers</a></span></dt></dl></dd><dt><span class="section"><a href="using_exceptions.html">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.safety">Exception Safety</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.propagating">Exception Neutrality</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.no">Doing without</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.compat">Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.c">With <code class="literal">C</code></a></span></dt><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.posix">With <code class="literal">POSIX</code> thread cancellation</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="debug.html">Debugging Support</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.compiler">Using <span class="command"><strong>g++</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.req">Debug Versions of Library Binary Files</a></span></dt><dt><span class="section"><a href="debug.html#debug.memory">Memory Leak Hunting</a></span></dt><dt><span class="section"><a href="debug.html#debug.races">Data Race Hunting</a></span></dt><dt><span class="section"><a href="debug.html#debug.gdb">Using <span class="command"><strong>gdb</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.exceptions">Tracking uncaught exceptions</a></span></dt><dt><span class="section"><a href="debug.html#debug.debug_mode">Debug Mode</a></span></dt><dt><span class="section"><a href="debug.html#debug.compile_time_checks">Compile Time Checking</a></span></dt><dt><span class="section"><a href="debug.html#debug.profile_mode">Profile-based Performance Analysis</a></span></dt></dl></dd></dl></dd></dl></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="index.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="index.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="status.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">The GNU C++ Library Manual </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 1. 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+</h1></div></div></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="chapter"><a href="status.html">1. Status</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#manual.intro.status.iso">Implementation Status</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#status.iso.1998">C++ 1998/2003</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.1998.status">Implementation Status</a></span></dt><dt><span class="section"><a href="status.html#iso.1998.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2011">C++ 2011</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2011.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2014">C++ 2014</a></span></dt><dt><span class="section"><a href="status.html#status.iso.2017">C++ 2017</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2017.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2020">C++ 202a</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2020.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.tr1">C++ TR1</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.tr1.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.tr24733">C++ TR 24733</a></span></dt><dt><span class="section"><a href="status.html#status.iso.specfun">C++ IS 29124</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.specfun.specific">Implementation Specific Behavior</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="license.html">License</a></span></dt><dd><dl><dt><span class="section"><a href="license.html#manual.intro.status.license.gpl">The Code: GPL</a></span></dt><dt><span class="section"><a href="license.html#manual.intro.status.license.fdl">The Documentation: GPL, FDL</a></span></dt></dl></dd><dt><span class="section"><a href="bugs.html">Bugs</a></span></dt><dd><dl><dt><span class="section"><a href="bugs.html#manual.intro.status.bugs.impl">Implementation Bugs</a></span></dt><dt><span class="section"><a href="bugs.html#manual.intro.status.bugs.iso">Standard Bugs</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="setup.html">2. Setup</a></span></dt><dd><dl><dt><span class="section"><a href="setup.html#manual.intro.setup.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="configure.html">Configure</a></span></dt><dt><span class="section"><a href="make.html">Make</a></span></dt></dl></dd><dt><span class="chapter"><a href="using.html">3. Using</a></span></dt><dd><dl><dt><span class="section"><a href="using.html#manual.intro.using.flags">Command Options</a></span></dt><dt><span class="section"><a href="using_headers.html">Headers</a></span></dt><dd><dl><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.all">Header Files</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.mixing">Mixing Headers</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.cheaders">The C Headers and <code class="code">namespace std</code></a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.pre">Precompiled Headers</a></span></dt></dl></dd><dt><span class="section"><a href="using_macros.html">Macros</a></span></dt><dt><span class="section"><a href="using_dual_abi.html">Dual ABI</a></span></dt><dd><dl><dt><span class="section"><a href="using_dual_abi.html#manual.intro.using.abi.trouble">Troubleshooting</a></span></dt></dl></dd><dt><span class="section"><a href="using_namespaces.html">Namespaces</a></span></dt><dd><dl><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.all">Available Namespaces</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.std">namespace std</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.comp">Using Namespace Composition</a></span></dt></dl></dd><dt><span class="section"><a href="using_dynamic_or_shared.html">Linking</a></span></dt><dd><dl><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.freestanding">Almost Nothing</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic">Finding Dynamic or Shared Libraries</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.experimental">Experimental Library Extensions</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html">Concurrency</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.thread_safety">Thread Safety</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.atomics">Atomics</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.io">IO</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#concurrency.io.structure">Structure</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.defaults">Defaults</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.future">Future</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.alt">Alternatives</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.containers">Containers</a></span></dt></dl></dd><dt><span class="section"><a href="using_exceptions.html">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.safety">Exception Safety</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.propagating">Exception Neutrality</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.no">Doing without</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.compat">Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.c">With <code class="literal">C</code></a></span></dt><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.posix">With <code class="literal">POSIX</code> thread cancellation</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="debug.html">Debugging Support</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.compiler">Using <span class="command"><strong>g++</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.req">Debug Versions of Library Binary Files</a></span></dt><dt><span class="section"><a href="debug.html#debug.memory">Memory Leak Hunting</a></span></dt><d
d><dl><dt><span class="section"><a href="debug.html#debug.memory.mtalloc">Non-memory leaks in Pool and MT allocators</a></span></dt></dl></dd><dt><span class="section"><a href="debug.html#debug.races">Data Race Hunting</a></span></dt><dt><span class="section"><a href="debug.html#debug.gdb">Using <span class="command"><strong>gdb</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.exceptions">Tracking uncaught exceptions</a></span></dt><dt><span class="section"><a href="debug.html#debug.debug_mode">Debug Mode</a></span></dt><dt><span class="section"><a href="debug.html#debug.compile_time_checks">Compile Time Checking</a></span></dt><dt><span class="section"><a href="debug.html#debug.profile_mode">Profile-based Performance Analysis</a></span></dt></dl></dd></dl></dd></dl></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="index.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="index.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="status.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">The GNU C++ Library Manual </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 1. Status</td></tr></table></div></body></html>
\ No newline at end of file
<code class="code">__gnu_parallel::_Settings::set</code>, respectively.
Please note that the first call return a const object, so direct manipulation
is forbidden.
-See <a class="link" href="http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/a01005.html" target="_top">
- <code class="filename">settings.h</code></a>
+See <a class="link" href="http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/index.html" target="_top">
+ <code class="filename"><parallel/settings.h></code></a>
for complete details.
</p><p>
A small example of tuning the default:
<a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0031r0.html" target="_top">
P0031R0
</a>
- </td><td align="center"> 7.1 </td><td align="left"><code class="code"> __cpp_lib_array_constexpr >= 201603 </code></td></tr><tr bgcolor="#C8B0B0"><td align="left"> The Parallelism TS Should be Standardized </td><td align="left">
+ </td><td align="center"> 7.1 </td><td align="left"><code class="code"> __cpp_lib_array_constexpr >= 201603 </code></td></tr><tr bgcolor="#B0B0B0"><td align="left"> The Parallelism TS Should be Standardized </td><td align="left">
<a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0024r2.html" target="_top">
P0024R2
</a>
- </td><td align="center"> No </td><td align="left"><code class="code"> __has_include(<execution>) </code>,
+ </td><td align="center"> 9.1 </td><td align="left"><code class="code"> __has_include(<execution>) </code>,
<code class="code"> __cpp_lib_execution >= 201603 </code>,
<code class="code"> __cpp_lib_parallel_algorithm >= 201603 </code>
+ (requires linking with <code class="code">-ltbb</code>, see Note 3)
</td></tr><tr><td align="left"> An algorithm to "clamp" a value between a pair of boundary values </td><td align="left">
<a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0025r0.html" target="_top">
P0025R0
P0226R1
</a>
</td><td align="center"> 7.1 </td><td align="left"><code class="code"> __cpp_lib_math_special_functions >= 201603 </code>
- (see Note 3)
+ (see Note 4)
</td></tr><tr><td align="left">Adopt the File System TS for C++17 </td><td align="left">
<a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0218r1.html" target="_top">
P0218R1
<code class="code">__cpp_lib</code> macro is not defined to the right value
(or not defined at all) until the version shown in parentheses.
</p><p>
-Note 3: The mathematical special functions are enabled in C++17 mode from
+Note 3: The Parallel Algorithms have an external dependency on Intel TBB 2018
+or later. If the <code class="filename"><execution></code>
+header is included then <code class="code">-ltbb</code> must be used to link to TBB.
+</p><p>
+Note 4: The mathematical special functions are enabled in C++17 mode from
GCC 7.1 onwards. For GCC 6.x or for C++11/C++14 define
<code class="code">__STDCPP_WANT_MATH_SPEC_FUNCS__</code> to a non-zero value
and test for <code class="code">__STDCPP_MATH_SPEC_FUNCS__ >= 201003L</code>.
<a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0608r3.html" target="_top">
P0608R3
</a>
- </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left"> <code class="code">visit<R></code>: Explicit Return Type for <code class="code">visit</code> </td><td align="left">
+ </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left"> <code class="code">visit<R></code>: Explicit Return Type for <code class="code">visit</code> </td><td align="left">
<a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0655r1.pdf" target="_top">
P0655R1
</a>
- </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left"> <code class="code">std::function</code> move constructor should be <code class="code">noexcept</code> </td><td align="left">
+ </td><td align="center"> 9.1 </td><td align="left"> </td></tr><tr><td align="left"> <code class="code">std::function</code> move constructor should be <code class="code">noexcept</code> </td><td align="left">
<a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0771r1.pdf" target="_top">
P0771R1
</a>
The header <code class="filename">limits</code> defines
traits classes to give access to various implementation
defined-aspects of the fundamental types. The traits classes --
- fourteen in total -- are all specializations of the template class
- <code class="classname">numeric_limits</code>, documented <a class="link" href="http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/a00593.html" target="_top">here</a>
+ fourteen in total -- are all specializations of the class template
+ <code class="classname">numeric_limits</code>
and defined as follows:
</p><pre class="programlisting">
template<typename T>
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-</th><td width="20%" align="right"> <a accesskey="n" href="using_headers.html">Next</a></td></tr></table><hr /></div><div class="chapter"><div class="titlepage"><div><div><h2 class="title"><a id="manual.intro.using"></a>Chapter 3. Using</h2></div></div></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="section"><a href="using.html#manual.intro.using.flags">Command Options</a></span></dt><dt><span class="section"><a href="using_headers.html">Headers</a></span></dt><dd><dl><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.all">Header Files</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.mixing">Mixing Headers</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.cheaders">The C Headers and <code class="code">namespace std</code></a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.pre">Precompiled Headers</a></span></dt></dl></dd><dt><span class="section"><a href="using_macros.html">Macros</a></span></dt><dt><span class="section"><a href="using_dual_abi.html">Dual ABI</a></span></dt><dd><dl><dt><span class="section"><a href="using_dual_abi.html#manual.intro.using.abi.trouble">Troubleshooting</a></span></dt></dl></dd><dt><span class="section"><a href="using_namespaces.html">Namespaces</a></span></dt><dd><dl><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.all">Available Namespaces</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.std">namespace std</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.comp">Using Namespace Composition</a></span></dt></dl></dd><dt><span class="section"><a href="using_dynamic_or_shared.html">Linking</a></span></dt><dd><dl><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.freestanding">Almost Nothing</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic">Finding Dynamic or Shared Libraries</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.experimental">Experimental Library Extensions</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html">Concurrency</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.thread_safety">Thread Safety</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.atomics">Atomics</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.io">IO</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#concurrency.io.structure">Structure</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.defaults">Defaults</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.future">Future</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.alt">Alternatives</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.containers">Containers</a></span></dt></dl></dd><dt><span class="section"><a href="using_exceptions.html">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.safety">Exception Safety</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.propagating">Exception Neutrality</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.no">Doing without</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.compat">Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.c">With <code class="literal">C</code></a></span></dt><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.posix">With <code class="literal">POSIX</code> thread cancellation</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="debug.html">Debugging Support</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.compiler">Using <span class="command"><strong>g++</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.req">Debug Versions of Library Binary Files</a></span></dt><dt><span class="section"><a href="debug.html#debug.memory">Memory Leak Hunting</a></span></dt><dt><span class="section"><a href="debug.html#debug.races">Data Race Hunting</a></span></dt><dt><span class="section"><a href="debug.html#debug.gdb">Using <span class="command"><strong>gdb</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.exceptions">Tracking uncaught exceptions</a></span></dt><dt><span class="section"><a href="debug.html#debug.debug_mode">Debug Mode</a></span></dt><dt><span class="section"><a href="debug.html#debug.compile_time_checks">Compile Time Checking</a></span></dt><dt><span class="section"><a href="debug.html#debug.profile_mode">Profile-based Performance Analysis</a></span></dt></dl></dd></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="manual.intro.using.flags"></a>Command Options</h2></div></div></div><p>
+</th><td width="20%" align="right"> <a accesskey="n" href="using_headers.html">Next</a></td></tr></table><hr /></div><div class="chapter"><div class="titlepage"><div><div><h2 class="title"><a id="manual.intro.using"></a>Chapter 3. Using</h2></div></div></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="section"><a href="using.html#manual.intro.using.flags">Command Options</a></span></dt><dt><span class="section"><a href="using_headers.html">Headers</a></span></dt><dd><dl><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.all">Header Files</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.mixing">Mixing Headers</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.cheaders">The C Headers and <code class="code">namespace std</code></a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.pre">Precompiled Headers</a></span></dt></dl></dd><dt><span class="section"><a href="using_macros.html">Macros</a></span></dt><dt><span class="section"><a href="using_dual_abi.html">Dual ABI</a></span></dt><dd><dl><dt><span class="section"><a href="using_dual_abi.html#manual.intro.using.abi.trouble">Troubleshooting</a></span></dt></dl></dd><dt><span class="section"><a href="using_namespaces.html">Namespaces</a></span></dt><dd><dl><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.all">Available Namespaces</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.std">namespace std</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.comp">Using Namespace Composition</a></span></dt></dl></dd><dt><span class="section"><a href="using_dynamic_or_shared.html">Linking</a></span></dt><dd><dl><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.freestanding">Almost Nothing</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic">Finding Dynamic or Shared Libraries</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.experimental">Experimental Library Extensions</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html">Concurrency</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.thread_safety">Thread Safety</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.atomics">Atomics</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.io">IO</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#concurrency.io.structure">Structure</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.defaults">Defaults</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.future">Future</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.alt">Alternatives</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.containers">Containers</a></span></dt></dl></dd><dt><span class="section"><a href="using_exceptions.html">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.safety">Exception Safety</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.propagating">Exception Neutrality</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.no">Doing without</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.compat">Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.c">With <code class="literal">C</code></a></span></dt><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.posix">With <code class="literal">POSIX</code> thread cancellation</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="debug.html">Debugging Support</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.compiler">Using <span class="command"><strong>g++</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.req">Debug Versions of Library Binary Files</a></span></dt><dt><span class="section"><a href="debug.html#debug.memory">Memory Leak Hunting</a></span></dt><d
d><dl><dt><span class="section"><a href="debug.html#debug.memory.mtalloc">Non-memory leaks in Pool and MT allocators</a></span></dt></dl></dd><dt><span class="section"><a href="debug.html#debug.races">Data Race Hunting</a></span></dt><dt><span class="section"><a href="debug.html#debug.gdb">Using <span class="command"><strong>gdb</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.exceptions">Tracking uncaught exceptions</a></span></dt><dt><span class="section"><a href="debug.html#debug.debug_mode">Debug Mode</a></span></dt><dt><span class="section"><a href="debug.html#debug.compile_time_checks">Compile Time Checking</a></span></dt><dt><span class="section"><a href="debug.html#debug.profile_mode">Profile-based Performance Analysis</a></span></dt></dl></dd></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="manual.intro.using.flags"></a>Command Options</h2></div></div></div><p>
The set of features available in the GNU C++ library is shaped by
several <a class="link" href="http://gcc.gnu.org/onlinedocs/gcc-4.3.2/gcc/Invoking-GCC.html" target="_top">GCC
Command Options</a>. Options that impact libstdc++ are
</td></tr><tr><td align="left"><code class="literal">-lstdc++fs</code></td><td align="left">Linking to <code class="filename">libstdc++fs</code>
is required for use of the Filesystem library extensions in
<code class="filename"><experimental/filesystem></code>.
- </td></tr><tr><td align="left"><code class="literal">-fopenmp</code></td><td align="left">For <a class="link" href="parallel_mode.html" title="Chapter 18. Parallel Mode">parallel</a> mode.</td></tr></tbody></table></div></div><br class="table-break" /></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="make.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="intro.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="using_headers.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Make </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Headers</td></tr></table></div></body></html>
\ No newline at end of file
+ </td></tr><tr><td align="left"><code class="literal">-fopenmp</code></td><td align="left">For <a class="link" href="parallel_mode.html" title="Chapter 18. Parallel Mode">parallel</a> mode.</td></tr><tr><td align="left"><code class="literal">-ltbb</code></td><td align="left">Linking to tbb (Thread Building Blocks) is required for use of the
+ Parallel Standard Algorithms and execution policies in
+ <code class="filename"><execution></code>.
+ </td></tr></tbody></table></div></div><br class="table-break" /></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="make.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="intro.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="using_headers.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Make </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Headers</td></tr></table></div></body></html>
\ No newline at end of file
</row>
<row>
- <?dbhtml bgcolor="#C8B0B0" ?>
+ <?dbhtml bgcolor="#B0B0B0" ?>
<entry> The Parallelism TS Should be Standardized </entry>
<entry>
<link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0024r2.html">
P0024R2
</link>
</entry>
- <entry align="center"> No </entry>
+ <entry align="center"> 9.1 </entry>
<entry><code> __has_include(<execution>) </code>,
<code> __cpp_lib_execution >= 201603 </code>,
<code> __cpp_lib_parallel_algorithm >= 201603 </code>
+ (requires linking with <code>-ltbb</code>, see Note 3)
</entry>
</row>
</entry>
<entry align="center"> 7.1 </entry>
<entry><code> __cpp_lib_math_special_functions >= 201603 </code>
- (see Note 3)
+ (see Note 4)
</entry>
</row>
</para>
<para>
-Note 3: The mathematical special functions are enabled in C++17 mode from
+Note 3: The Parallel Algorithms have an external dependency on Intel TBB 2018
+or later. If the <filename class="headerfile"><execution></filename>
+header is included then <code>-ltbb</code> must be used to link to TBB.
+</para>
+
+<para>
+Note 4: The mathematical special functions are enabled in C++17 mode from
GCC 7.1 onwards. For GCC 6.x or for C++11/C++14 define
<code>__STDCPP_WANT_MATH_SPEC_FUNCS__</code> to a non-zero value
and test for <code>__STDCPP_MATH_SPEC_FUNCS__ >= 201003L</code>.
projects / thirdparty / gcc.git / commitdiff
