Document C++20 library status

	* doc/xml/manual/intro.xml: Include new section.
	* doc/xml/manual/status_cxx2017.xml: Document more
	implementation-defined properties of the library.
	* doc/xml/manual/status_cxx2020.xml: Document C++2a status.
	* doc/html/*: Regenerate.

From-SVN: r267867

8 files changed, 1411 insertions, 26 deletions

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 9ae1fce..c89ab4a 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,5 +1,11 @@
 2019-01-11  Jonathan Wakely  <jwakely@redhat.com>
 
+	* doc/xml/manual/intro.xml: Include new section.
+	* doc/xml/manual/status_cxx2017.xml: Document more
+	implementation-defined properties of the library.
+	* doc/xml/manual/status_cxx2020.xml: Document C++2a status.
+	* doc/html/*: Regenerate.
+
 	* include/bits/refwrap.h [__cplusplus > 201703L]
 	(_Refwrap_base_arg1, _Refwrap_base_arg2, _Reference_wrapper_base)
 	(_Reference_wrapper_base_memfun): Do not define for C++2a.
diff --git a/libstdc++-v3/doc/html/index.html b/libstdc++-v3/doc/html/index.html
index 48a5014..576e963 100644
--- a/libstdc++-v3/doc/html/index.html
+++ b/libstdc++-v3/doc/html/index.html
@@ -23,7 +23,7 @@
     </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.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><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
diff --git a/libstdc++-v3/doc/html/manual/index.html b/libstdc++-v3/doc/html/manual/index.html
index 675505e..0761c55 100644
--- a/libstdc++-v3/doc/html/manual/index.html
+++ b/libstdc++-v3/doc/html/manual/index.html
@@ -4,7 +4,7 @@
     </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.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><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
@@ -149,7 +149,7 @@ Support for C++11 dialect.
 	  </a></dt><dt>22.10. <a href="policy_data_structures_design.html#id-1.3.5.9.4.3.3.3.23">Non-unique Mapping Containers</a></dt><dt>22.11. <a href="policy_data_structures_design.html#id-1.3.5.9.4.3.4.3.5">Point Iterator Hierarchy</a></dt><dt>22.12. <a href="policy_data_structures_design.html#id-1.3.5.9.4.3.4.4.5">Invalidation Guarantee Tags Hierarchy</a></dt><dt>22.13. <a href="policy_data_structures_design.html#id-1.3.5.9.4.3.5.7.4">Container Tag Hierarchy</a></dt><dt>22.14. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.2.2.3">Hash functions, ranged-hash functions, and
 	      range-hashing functions</a></dt><dt>22.15. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.2.5.3.4">Insert hash sequence diagram</a></dt><dt>22.16. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.2.5.3.6">Insert hash sequence diagram with a null policy</a></dt><dt>22.17. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.2.5.5.5">Hash policy class diagram</a></dt><dt>22.18. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.3.4.7">Balls and bins</a></dt><dt>22.19. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.3.5.3.6">Insert resize sequence diagram</a></dt><dt>22.20. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.3.5.3.9">Standard resize policy trigger sequence
 		diagram</a></dt><dt>22.21. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.3.5.3.10">Standard resize policy size sequence
-		diagram</a></dt><dt>22.22. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.3.3.2.5">Tree node invariants</a></dt><dt>22.23. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.3.3.2.8">Tree node invalidation</a></dt><dt>22.24. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.3.3.2.11.3">A tree and its update policy</a></dt><dt>22.25. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.3.3.2.11.8">Restoring node invariants</a></dt><dt>22.26. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.3.3.2.11.10">Insert update sequence</a></dt><dt>22.27. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.3.3.2.11.20">Useless update path</a></dt><dt>22.28. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.4.3.2.10">A PATRICIA trie</a></dt><dt>22.29. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.4.3.3.5">A trie and its update policy</a></dt><dt>22.30. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.5.3.3.3">A simple list</a></dt><dt>22.31. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.5.3.3.6">The counter algorithm</a></dt><dt>22.32. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.6.3.3.3">Underlying Priority-Queue Data-Structures.</a></dt><dt>22.33. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.6.3.4.4">Priority-Queue Data-Structure Tags.</a></dt><dt>B.1. <a href="appendix_porting.html#fig.build_hacking.deps">Configure and Build File Dependencies</a></dt></dl></div><div class="list-of-tables"><p><strong>List of Tables</strong></p><dl><dt>1.1. <a href="status.html#table.cxx98_status">C++ 1998/2003 Implementation Status</a></dt><dt>1.2. <a href="status.html#table.cxx11_status">C++ 2011 Implementation Status</a></dt><dt>1.3. <a href="status.html#table.cxx14_status">C++ 2014 Implementation Status</a></dt><dt>1.4. <a href="status.html#table.ts_status">C++ Technical Specifications Implementation Status</a></dt><dt>1.5. <a href="status.html#table.cxx17_status">C++ 2017 Implementation Status</a></dt><dt>1.6. <a href="status.html#table.cxx17_ts_status">C++ Technical Specifications Implementation Status</a></dt><dt>1.7. <a href="status.html#table.tr1_status">C++ TR1 Implementation Status</a></dt><dt>1.8. <a href="status.html#table.decfp_status">C++ TR 24733 Implementation Status</a></dt><dt>1.9. <a href="status.html#table.specfun_status">C++ Special Functions Implementation Status</a></dt><dt>3.1. <a href="using.html#table.cmd_options">C++ Command Options</a></dt><dt>3.2. <a href="using_headers.html#table.cxx98_headers">C++ 1998 Library Headers</a></dt><dt>3.3. <a href="using_headers.html#table.cxx98_cheaders">C++ 1998 Library Headers for C Library Facilities</a></dt><dt>3.4. <a href="using_headers.html#table.cxx98_deprheaders">C++ 1998 Deprecated Library Header</a></dt><dt>3.5. <a href="using_headers.html#table.cxx11_headers">C++ 2011 Library Headers</a></dt><dt>3.6. <a href="using_headers.html#table.cxx11_cheaders">C++ 2011 Library Headers for C Library Facilities</a></dt><dt>3.7. <a href="using_headers.html#table.cxx14_headers">C++ 2014 Library Header</a></dt><dt>3.8. <a href="using_headers.html#table.cxx17_headers">C++ 2017 Library Headers</a></dt><dt>3.9. <a href="using_headers.html#table.cxx20_headers">C++ 2020 Library Headers</a></dt><dt>3.10. <a href="using_headers.html#table.cxx20_deprheaders">C++ 2020 Obsolete Headers</a></dt><dt>3.11. <a href="using_headers.html#table.filesystemts_headers">File System TS Header</a></dt><dt>3.12. <a href="using_headers.html#table.libfundts_headers">Library Fundamentals TS Headers</a></dt><dt>3.13. <a href="using_headers.html#table.tr1_headers">C++ TR 1 Library Headers</a></dt><dt>3.14. <a href="using_headers.html#table.tr1_cheaders">C++ TR 1 Library Headers for C Library Facilities</a></dt><dt>3.15. <a href="using_headers.html#table.decfp_headers">C++ TR 24733 Decimal Floating-Point Header</a></dt><dt>3.16. <a href="using_headers.html#table.abi_headers">C++ ABI Headers</a></dt><dt>3.17. <a href="using_headers.html#table.ext_headers">Extension Headers</a></dt><dt>3.18. <a href="using_headers.html#table.debug_headers">Extension Debug Headers</a></dt><dt>3.19. <a href="using_headers.html#table.profile_headers">Extension Profile Headers</a></dt><dt>3.20. <a href="using_headers.html#table.parallel_headers">Extension Parallel Headers</a></dt><dt>17.1. <a href="debug_mode_using.html#table.debug_mode_containers">Debugging Containers</a></dt><dt>17.2. <a href="debug_mode_using.html#table.debug_mode_containers_cxx11">Debugging Containers C++11</a></dt><dt>18.1. <a href="parallel_mode_using.html#table.parallel_algos">Parallel Algorithms</a></dt><dt>19.1. <a href="profile_mode_design.html#table.profile_code_loc">Profile Code Location</a></dt><dt>19.2. <a href="profile_mode_diagnostics.html#table.profile_diagnostics">Profile Diagnostics</a></dt><dt>21.1. <a href="bitmap_allocator_impl.html#table.bitmap_alloc">Bitmap Allocator Memory Map</a></dt><dt>B.1. <a href="documentation_hacking.html#table.doxygen_prereq">Doxygen Prerequisites</a></dt><dt>B.2. <a href="documentation_hacking.html#table.doxygen_cmp">HTML to Doxygen Markup Comparison</a></dt><dt>B.3. <a href="documentation_hacking.html#table.docbook_prereq">Docbook Prerequisites</a></dt><dt>B.4. <a href="documentation_hacking.html#table.docbook_cmp">HTML to Docbook XML Markup Comparison</a></dt><dt>B.5. <a href="documentation_hacking.html#table.docbook_elem">Docbook XML Element Use</a></dt><dt>B.6. <a href="api.html#table.extension_allocators">Extension Allocators</a></dt><dt>B.7. <a href="api.html#table.extension_allocators2">Extension Allocators Continued</a></dt></dl></div><div class="list-of-equations"><p><strong>List of Equations</strong></p><dl><dt>22.1. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.2.2.15">Ranged Hash Function</a></dt><dt>22.2. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.2.3.3">Range-Hashing, Division Method</a></dt><dt>22.3. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.2.3.9">Division via Prime Modulo</a></dt><dt>22.4. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.2.3.11">Division via Bit Mask</a></dt><dt>22.5. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.2.4.7">
+		diagram</a></dt><dt>22.22. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.3.3.2.5">Tree node invariants</a></dt><dt>22.23. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.3.3.2.8">Tree node invalidation</a></dt><dt>22.24. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.3.3.2.11.3">A tree and its update policy</a></dt><dt>22.25. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.3.3.2.11.8">Restoring node invariants</a></dt><dt>22.26. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.3.3.2.11.10">Insert update sequence</a></dt><dt>22.27. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.3.3.2.11.20">Useless update path</a></dt><dt>22.28. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.4.3.2.10">A PATRICIA trie</a></dt><dt>22.29. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.4.3.3.5">A trie and its update policy</a></dt><dt>22.30. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.5.3.3.3">A simple list</a></dt><dt>22.31. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.5.3.3.6">The counter algorithm</a></dt><dt>22.32. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.6.3.3.3">Underlying Priority-Queue Data-Structures.</a></dt><dt>22.33. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.6.3.4.4">Priority-Queue Data-Structure Tags.</a></dt><dt>B.1. <a href="appendix_porting.html#fig.build_hacking.deps">Configure and Build File Dependencies</a></dt></dl></div><div class="list-of-tables"><p><strong>List of Tables</strong></p><dl><dt>1.1. <a href="status.html#table.cxx98_status">C++ 1998/2003 Implementation Status</a></dt><dt>1.2. <a href="status.html#table.cxx11_status">C++ 2011 Implementation Status</a></dt><dt>1.3. <a href="status.html#table.cxx14_status">C++ 2014 Implementation Status</a></dt><dt>1.4. <a href="status.html#table.ts_status">C++ Technical Specifications Implementation Status</a></dt><dt>1.5. <a href="status.html#table.cxx17_status">C++ 2017 Implementation Status</a></dt><dt>1.6. <a href="status.html#table.cxx17_ts_status">C++ Technical Specifications Implementation Status</a></dt><dt>1.7. <a href="status.html#table.cxx20_status">C++ 2020 Implementation Status</a></dt><dt>1.8. <a href="status.html#table.tr1_status">C++ TR1 Implementation Status</a></dt><dt>1.9. <a href="status.html#table.decfp_status">C++ TR 24733 Implementation Status</a></dt><dt>1.10. <a href="status.html#table.specfun_status">C++ Special Functions Implementation Status</a></dt><dt>3.1. <a href="using.html#table.cmd_options">C++ Command Options</a></dt><dt>3.2. <a href="using_headers.html#table.cxx98_headers">C++ 1998 Library Headers</a></dt><dt>3.3. <a href="using_headers.html#table.cxx98_cheaders">C++ 1998 Library Headers for C Library Facilities</a></dt><dt>3.4. <a href="using_headers.html#table.cxx98_deprheaders">C++ 1998 Deprecated Library Header</a></dt><dt>3.5. <a href="using_headers.html#table.cxx11_headers">C++ 2011 Library Headers</a></dt><dt>3.6. <a href="using_headers.html#table.cxx11_cheaders">C++ 2011 Library Headers for C Library Facilities</a></dt><dt>3.7. <a href="using_headers.html#table.cxx14_headers">C++ 2014 Library Header</a></dt><dt>3.8. <a href="using_headers.html#table.cxx17_headers">C++ 2017 Library Headers</a></dt><dt>3.9. <a href="using_headers.html#table.cxx20_headers">C++ 2020 Library Headers</a></dt><dt>3.10. <a href="using_headers.html#table.cxx20_deprheaders">C++ 2020 Obsolete Headers</a></dt><dt>3.11. <a href="using_headers.html#table.filesystemts_headers">File System TS Header</a></dt><dt>3.12. <a href="using_headers.html#table.libfundts_headers">Library Fundamentals TS Headers</a></dt><dt>3.13. <a href="using_headers.html#table.tr1_headers">C++ TR 1 Library Headers</a></dt><dt>3.14. <a href="using_headers.html#table.tr1_cheaders">C++ TR 1 Library Headers for C Library Facilities</a></dt><dt>3.15. <a href="using_headers.html#table.decfp_headers">C++ TR 24733 Decimal Floating-Point Header</a></dt><dt>3.16. <a href="using_headers.html#table.abi_headers">C++ ABI Headers</a></dt><dt>3.17. <a href="using_headers.html#table.ext_headers">Extension Headers</a></dt><dt>3.18. <a href="using_headers.html#table.debug_headers">Extension Debug Headers</a></dt><dt>3.19. <a href="using_headers.html#table.profile_headers">Extension Profile Headers</a></dt><dt>3.20. <a href="using_headers.html#table.parallel_headers">Extension Parallel Headers</a></dt><dt>17.1. <a href="debug_mode_using.html#table.debug_mode_containers">Debugging Containers</a></dt><dt>17.2. <a href="debug_mode_using.html#table.debug_mode_containers_cxx11">Debugging Containers C++11</a></dt><dt>18.1. <a href="parallel_mode_using.html#table.parallel_algos">Parallel Algorithms</a></dt><dt>19.1. <a href="profile_mode_design.html#table.profile_code_loc">Profile Code Location</a></dt><dt>19.2. <a href="profile_mode_diagnostics.html#table.profile_diagnostics">Profile Diagnostics</a></dt><dt>21.1. <a href="bitmap_allocator_impl.html#table.bitmap_alloc">Bitmap Allocator Memory Map</a></dt><dt>B.1. <a href="documentation_hacking.html#table.doxygen_prereq">Doxygen Prerequisites</a></dt><dt>B.2. <a href="documentation_hacking.html#table.doxygen_cmp">HTML to Doxygen Markup Comparison</a></dt><dt>B.3. <a href="documentation_hacking.html#table.docbook_prereq">Docbook Prerequisites</a></dt><dt>B.4. <a href="documentation_hacking.html#table.docbook_cmp">HTML to Docbook XML Markup Comparison</a></dt><dt>B.5. <a href="documentation_hacking.html#table.docbook_elem">Docbook XML Element Use</a></dt><dt>B.6. <a href="api.html#table.extension_allocators">Extension Allocators</a></dt><dt>B.7. <a href="api.html#table.extension_allocators2">Extension Allocators Continued</a></dt></dl></div><div class="list-of-equations"><p><strong>List of Equations</strong></p><dl><dt>22.1. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.2.2.15">Ranged Hash Function</a></dt><dt>22.2. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.2.3.3">Range-Hashing, Division Method</a></dt><dt>22.3. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.2.3.9">Division via Prime Modulo</a></dt><dt>22.4. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.2.3.11">Division via Bit Mask</a></dt><dt>22.5. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.2.4.7">
 		A Standard String Hash Function
 	      </a></dt><dt>22.6. <a href="policy_data_structures_design.html#id-1.3.5.9.4.4.2.3.2.4.12">
 		Only k String DNA Hash
diff --git a/libstdc++-v3/doc/html/manual/intro.html b/libstdc++-v3/doc/html/manual/intro.html
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@@ -5,4 +5,4 @@
 </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.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. Status</td></tr></table></div></body></html>
\ No newline at end of file
+</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. Status</td></tr></table></div></body></html>
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diff --git a/libstdc++-v3/doc/html/manual/status.html b/libstdc++-v3/doc/html/manual/status.html
index 1e32879..12853f7 100644
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+++ b/libstdc++-v3/doc/html/manual/status.html
@@ -2,7 +2,7 @@
 <!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 1. Status</title><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><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="intro.html" title="Part I.  Introduction" /><link rel="prev" href="intro.html" title="Part I.  Introduction" /><link rel="next" href="license.html" title="License" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 1. Status</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="intro.html">Prev</a> </td><th width="60%" align="center">Part I. 
   Introduction
   
-</th><td width="20%" align="right"> <a accesskey="n" href="license.html">Next</a></td></tr></table><hr /></div><div class="chapter"><div class="titlepage"><div><div><h2 class="title"><a id="manual.intro.status"></a>Chapter 1. Status</h2></div></div></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><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.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></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="manual.intro.status.iso"></a>Implementation Status</h2></div></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="status.iso.1998"></a>C++ 1998/2003</h3></div></div></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="iso.1998.status"></a>Implementation Status</h4></div></div></div><p>
+</th><td width="20%" align="right"> <a accesskey="n" href="license.html">Next</a></td></tr></table><hr /></div><div class="chapter"><div class="titlepage"><div><div><h2 class="title"><a id="manual.intro.status"></a>Chapter 1. Status</h2></div></div></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><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></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="manual.intro.status.iso"></a>Implementation Status</h2></div></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="status.iso.1998"></a>C++ 1998/2003</h3></div></div></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="iso.1998.status"></a>Implementation Status</h4></div></div></div><p>
 This status table is based on the table of contents of ISO/IEC 14882:2003.
 </p><p>
 This page describes the C++ support in mainline GCC SVN, not in any
@@ -891,24 +891,35 @@ and test for <code class="code">__STDCPP_MATH_SPEC_FUNCS__ &gt;= 201003L</code>.
       2011 Implementation Specific Behavior</a>. This section only
       documents behaviour which is new in the 2017 standard.
    </p><p>
+      <span class="emphasis"><em>20.5.1.2 [headers]</em></span>
+      Whether names from Annex K are declared by C++ headers depends on
+      whether the underlying C library supports Annex K and declares the
+      names. For the GNU C library, there is no Annex K support and so
+      none of its names are declared by C++ headers.
+   </p><p>
       <span class="emphasis"><em>23.6.5 [optional.bad_optional_access]</em></span>
       <code class="code">what()</code> returns <code class="literal">"bad optional access"</code>.
    </p><p>
       <span class="emphasis"><em>23.7.3 [variant.variant]</em></span>
-      Whether <code class="classname">variant</code> supports over-aligned types
-      should be documented here.
+      <code class="classname">variant</code> supports over-aligned types.
    </p><p>
       <span class="emphasis"><em>23.7.10 [variant.bad.access]</em></span>
       <code class="code">what()</code> returns <code class="literal">"Unexpected index"</code>.
    </p><p>
       <span class="emphasis"><em>23.12.5.2 [memory.resource.pool.options]</em></span>
-      The limits for maximum number of blocks and largest allocation size
-      supported by <code class="classname">pool_options</code> should be documented
-      here.
+      Let S equal <code class="code">numeric_limits&lt;size_t&gt;::digits</code>.
+      The limit for maximum number of blocks in a chunk is given by
+      <span class="mathphrase">2<sup>N</sup>-1</span>,
+      where N is <span class="mathphrase">min(19, 3 + S/2)</span>.
+      The largest allocation size that will be allocated from a pool is
+      <span class="mathphrase">2<sup>22</sup></span>
+      when <span class="mathphrase">S &gt; 20</span>,
+      otherwise 3072 when <span class="mathphrase">S &gt; 16</span>,
+      otherwise 768.
    </p><p>
       <span class="emphasis"><em>23.12.6.1 [memory.resource.monotonic.buffer.ctor]</em></span>
-      The default <code class="code">next_buffer_size</code> and growth factor should
-      be documented here.
+      The default <code class="code">next_buffer_size</code> is <code class="code">128 * sizeof(void*)</code>.
+      The default growth factor is <code class="code">1.5</code>.
    </p><p>
       <span class="emphasis"><em>23.15.4.3 [meta.unary.prop]</em></span>
       The predicate condition for
@@ -950,11 +961,363 @@ and test for <code class="code">__STDCPP_MATH_SPEC_FUNCS__ &gt;= 201003L</code>.
       on some targets.
    </p><p>
       <span class="emphasis"><em>30.10.5 [fs.filesystem.syn]</em></span>
-      The clock used for file times is
-      <code class="classname">std::chrono::system_clock</code>.
+      The clock used for file times is an unspecified type
+      with a signed 64-bit representation, capable of representing
+      timestamps with nanosecond resolution. The clock's epoch is
+      unspecified, but is not the same as the system clock's epoch.
    </p><p>
       <span class="emphasis"><em>30.10.7.1 [fs.path.generic]</em></span>
       dot-dot in the root-directory refers to the root-directory itself.
+      On Windows, a drive specifier such as <code class="code">"C:"</code> or
+      <code class="code">"z:"</code> is treated as a root-name. On Cygwin, a path
+      that begins with two successive directory separators is a
+      root-name. Otherwise (for POSIX-like systems other than Cygwin),
+      the implementation-defined root-name is an unspecified string
+      which does not appear in any pathnames.
+   </p><p>
+      <span class="emphasis"><em>30.10.10.1 [fs.enum.path.format]</em></span>
+      The character sequence is always interpreted in the native pathname
+      format.
+   </p><p>
+      <span class="emphasis"><em>30.10.15.4 [fs.op.file_size]</em></span>
+      If <code class="code">!is_regular_file(p)</code>, an error is reported.
+   </p></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="status.iso.2020"></a>C++ 202a</h3></div></div></div><p>
+In this implementation the <code class="literal">-std=gnu++2a</code> or
+<code class="literal">-std=c++2a</code> flag must be used to enable language
+and library
+features. See <a class="link" href="using.html#manual.intro.using.flags" title="Command Options">dialect</a>
+options. The pre-defined symbol
+<code class="constant">__cplusplus</code> is used to check for the
+presence of the required flag.
+</p><p>
+This section describes the C++20 and library TS support in mainline GCC SVN,
+not in any particular release.
+</p><p>
+The following table lists new library features that have been accepted into
+the C++2a working draft. The "Proposal" column provides a link to the
+ISO C++ committee proposal that describes the feature, while the "Status"
+column indicates the first version of GCC that contains an implementation of
+this feature (if it has been implemented).
+The "SD-6 Feature Test" column shows the corresponding macro or header from
+<a class="link" href="https://isocpp.org/std/standing-documents/sd-6-sg10-feature-test-recommendations" target="_top">SD-6:
+Feature-testing recommendations for C++</a>.
+</p><div class="table"><a id="table.cxx20_status"></a><p class="title"><strong>Table 1.7. C++ 2020 Implementation Status</strong></p><div class="table-contents"><table class="table" summary="C++ 2020 Implementation Status" border="1"><colgroup><col align="left" class="c1" /><col align="left" class="c2" /><col align="left" class="c3" /><col align="left" class="c4" /></colgroup><thead><tr><th align="left">Library Feature</th><th align="left">Proposal</th><th align="left">Status</th><th align="left">SD-6 Feature Test</th></tr></thead><tbody><tr><td align="left">  Endian just Endian </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0463r1.html" target="_top">
+	P0463R1
+	</a>
+      </td><td align="center"> 8.1 </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Extending <code class="code">make_shared</code> to Support Arrays </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0674r1.html" target="_top">
+	P0674R1
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Floating Point Atomic </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0020r6.html" target="_top">
+	P0020R6
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  C++ Synchronized Buffered Ostream </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0053r7.pdf" target="_top">
+	P0053R7
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Add constexpr modifiers to functions in <code class="code">&lt;algorithm&gt;</code> and <code class="code">&lt;utility&gt;</code> Headers </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0202r3.html" target="_top">
+	P0202R3
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left">  Constexpr for <code class="code">std::complex</code> </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0415r1.html" target="_top">
+	P0415R1
+	</a>
+      </td><td align="center"> 9.1 </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Make <code class="code">std::memory_order</code> a scoped enumeration </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0439r0.html" target="_top">
+	P0439R0
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left">  String Prefix and Suffix Checking </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0457r2.html" target="_top">
+	P0457R2
+	</a>
+      </td><td align="center"> 9.1 </td><td align="left"> </td></tr><tr><td align="left">  Transformation Trait <code class="code">remove_cvref</code> </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0550r2.pdf" target="_top">
+	P0550R2
+	</a>
+      </td><td align="center"> 9.1 </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  <code class="code">nodiscard</code> in the Library </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0600r1.pdf" target="_top">
+	P0600R1
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  de-pessimize legacy algorithms with <code class="code">std::move</code> </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0616r0.pdf" target="_top">
+	P0616R0
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left">  Utility to convert a pointer to a raw pointer </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0653r2.html" target="_top">
+	P0653R2
+	</a>
+      </td><td align="center"> 8.1 </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Atomic <code class="code">shared_ptr</code> </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0718r2.html" target="_top">
+	P0718R2
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Deprecate POD </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0767r1.html" target="_top">
+	P0767R1
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Library Support for the Spaceship (Comparison) Operator </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0768r1.pdf" target="_top">
+	P0768R1
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Treating Unnecessary <code class="code">decay</code> </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0777r1.pdf" target="_top">
+	P0777R1
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  <code class="code">&lt;span&gt;</code> </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0122r7.pdf" target="_top">
+	P0122R7
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Extending chrono to Calendars and Time Zones </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0355r7.html" target="_top">
+	P0355R7
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Thou Shalt Not Specialize std Function Templates! </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0551r3.pdf" target="_top">
+	P0551R3
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Manipulators for C++ Synchronized Buffered Ostream </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0753r2.pdf" target="_top">
+	P0753R2
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left">  <code class="code">&lt;version&gt;</code> </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0754r2.pdf" target="_top">
+	P0754R2
+	</a>
+      </td><td align="center"> 9.1 </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Comparing Unordered Containers </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0809r0.pdf" target="_top">
+	P0809R0
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Constexpr iterator requirements </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0858r0.html" target="_top">
+	P0858R0
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Symmetry for spaceship </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0905r1.html" target="_top">
+	P0905R1
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  <code class="code">string::reserve</code> Should Not Shrink </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0966r1.html" target="_top">
+	P0966R1
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Atomic Ref </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0019r8.html" target="_top">
+	P0019R8
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left">  Checking for Existence of an Element in Associative Containers </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0458r2.html" target="_top">
+	P0458R2
+	</a>
+      </td><td align="center"> 9.1 </td><td align="left"> </td></tr><tr><td align="left">  LWG 2511: guaranteed copy elision for piecewise construction </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0475r1.html" target="_top">
+	P0475R1
+	</a>
+      </td><td align="center"> 7.1 </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Bit-casting object representations </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0476r2.html" target="_top">
+	P0476R2
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  The Curious Case of Padding Bits, Featuring Atomic Compare-and-Exchange </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0528r3.html" target="_top">
+	P0528R3
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Support for contract based programming in C++ </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0542r5.html" target="_top">
+	P0542R5
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left">  Integral power-of-2 operations </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0556r3.html" target="_top">
+	P0556R3
+	</a>
+      </td><td align="center"> 9.1 </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Reviewing Deprecated Facilities of C++17 for C++20 </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0619r4.html" target="_top">
+	P0619R4
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left">  Improving the Return Value of Erase-Like Algorithms </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0646r1.pdf" target="_top">
+	P0646R1
+	</a>
+      </td><td align="center"> 9.1 </td><td align="left"> <code class="code">__cpp_lib_list_remove_return_type &gt;= 201806L</code> </td></tr><tr><td align="left">  Efficient sized delete for variable sized classes </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0722r3.html" target="_top">
+	P0722R3
+	</a>
+      </td><td align="center"> 9.1 </td><td align="left"> <code class="code">__cpp_lib_destroying_delete &gt;= 201806L</code> </td></tr><tr><td align="left">  Implicit conversion traits and utility functions </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0758r1.html" target="_top">
+	P0758R1
+	</a>
+      </td><td align="center"> 9.1 </td><td align="left"> </td></tr><tr><td align="left">  <code class="code">fpos</code> Requirements </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0759r1.html" target="_top">
+	P0759R1
+	</a>
+      </td><td align="center"> Note 1 </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Add <code class="code">shift</code> to <code class="code">&lt;algorithm&gt;</code> </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0769r2.pdf" target="_top">
+	P0769R2
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Standard Library Specification in a Concepts and Contracts World </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0788r3.pdf" target="_top">
+	P0788R3
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Constexpr for <code class="code">swap</code> and swap related functions </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0879r0.html" target="_top">
+	P0879R0
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  The <code class="code">identity</code> metafunction </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0887r1.pdf" target="_top">
+	P0887R1
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left">  <code class="code">explicit(bool)</code> </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0892r2.html" target="_top">
+	P0892R2
+	</a>
+      </td><td align="center"> Note 1 </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Standard Library Concepts </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0898r3.pdf" target="_top">
+	P0898R3
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left">  Eradicating unnecessarily explicit default constructors from the standard library </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0935r0.html" target="_top">
+	P0935R0
+	</a>
+      </td><td align="center"> 9.1 </td><td align="left"> </td></tr><tr><td align="left">  Integrating feature-test macros into the C++ WD </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0941r2.html" target="_top">
+	P0941R2
+	</a>
+      </td><td align="center"> 5.1 </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  <code class="code">constexpr</code> comparison operators for <code class="code">std::array</code> </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1023r0.pdf" target="_top">
+	P1023R0
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Update The Reference To The Unicode Standard </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1025r1.html" target="_top">
+	P1025R1
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Consistency improvements for <code class="code">&lt;=&gt;</code> and other comparison operators </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1120r0.html" target="_top">
+	P1120R0
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left">  <code class="code">unwrap_ref_decay</code> and <code class="code">unwrap_reference</code> </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0318r1.pdf" target="_top">
+	P0318R1
+	</a>
+      </td><td align="center"> 9.1 </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Simplified partial function application </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0356r5.html" target="_top">
+	P0356R5
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left">  <code class="code">reference_wrapper</code> for incomplete types </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0357r3.html" target="_top">
+	P0357R3
+	</a>
+      </td><td align="center"> 9.1 </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  <code class="code">char8_t</code>: A type for UTF-8 characters and strings </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0482r6.html" target="_top">
+	P0482R6
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Fixing <code class="code">operator&gt;&gt;(basic_istream&amp;, CharT*)</code> (LWG 2499) </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0487r1.html" target="_top">
+	P0487R1
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Utility functions to implement uses-allocator construction </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0591r4.pdf" target="_top">
+	P0591R4
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left">  P0595R2 <code class="code">std::is_constant_evaluated()</code> </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0595r2.html" target="_top">
+	P0595R2
+	</a>
+      </td><td align="center"> 9.1 </td><td align="left"> </td></tr><tr><td align="left">  <code class="code">variant</code> and <code class="code">optional</code> should propagate copy/move triviality </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0602r4.html" target="_top">
+	P0602R4
+	</a>
+      </td><td align="center"> 8.3 </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  A sane <code class="code">variant</code> converting constructor </td><td align="left">
+        <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&lt;R&gt;</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">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0771r1.pdf" target="_top">
+	P0771R1
+	</a>
+      </td><td align="center"> 7.2 </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  The One Ranges Proposal </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0896r4.pdf" target="_top">
+	P0896R4
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left">  P0899R1 - LWG 3016 is not a defect </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0899r1.html" target="_top">
+	P0899R1
+	</a>
+      </td><td align="center"> 7.1 </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Heterogeneous lookup for unordered containers </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0919r3.html" target="_top">
+	P0919R3
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left">  <code class="code">&lt;chrono&gt;</code> <code class="code">zero()</code>, <code class="code">min()</code>, and <code class="code">max()</code> 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/p0972r0.pdf" target="_top">
+	P0972R0
+	</a>
+      </td><td align="center"> 9.1 </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Constexpr in <code class="code">std::pointer_traits</code> </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1006r1.pdf" target="_top">
+	P1006R1
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  <code class="code">std::assume_aligned</code> </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1007r3.pdf" target="_top">
+	P1007R3
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Smart pointer creation with default initialization </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1020r1.html" target="_top">
+	P1020R1
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Misc constexpr bits </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1032r1.html" target="_top">
+	P1032R1
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Should Span be Regular? </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1085r2.md" target="_top">
+	P1085R2
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Editorial Guidance for merging P0019r8 and P0528r3 </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1123r0.html" target="_top">
+	P1123R0
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Cleaning up Clause 20 </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1148r0.pdf" target="_top">
+	P1148R0
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Make stateful allocator propagation more consistent for <code class="code">operator+(basic_string)</code> </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1165r1.html" target="_top">
+	P1165R1
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr><td align="left">  Adopt Consistent Container Erasure from Library Fundamentals 2 for C++20 </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html" target="_top">
+	P1209R0
+	</a>
+      </td><td align="center"> 9.1 </td><td align="left"> <code class="code">__cpp_lib_erase_if &gt;= 201811L</code> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Completing the Rebase of Library Fundamentals, Version 3, Working Draft </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1210r0.html" target="_top">
+	P1210R0
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Alternative Wording for P0907R4 Signed Integers are Two's Complement </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1236r1.html" target="_top">
+	P1236R1
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Remove CommonReference requirement from StrictWeakOrdering (a.k.a Fixing Relations) </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1248r1.html" target="_top">
+	P1248R1
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#C8B0B0"><td align="left">  Improving Completeness Requirements for Type Traits </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1285r0.pdf" target="_top">
+	P1285R0
+	</a>
+      </td><td align="center"> </td><td align="left"> </td></tr><tr bgcolor="#B0B0B0"><td align="left">  Missing feature test macros </td><td align="left">
+        <a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1353r0.html" target="_top">
+	P1353R0
+	</a>
+      </td><td align="center"> Partial </td><td align="left"> </td></tr></tbody></table></div></div><br class="table-break" /><p>
+Note 1: The changes in the proposal either do not affect the code in libstdc++,
+or the changes are not required for conformance.
+</p><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="iso.2020.specific"></a>Implementation Specific Behavior</h4></div></div></div><p>For behaviour which is also specified by previous standards,
+      see <a class="link" href="status.html#iso.1998.specific" title="Implementation Specific Behavior">C++ 1998/2003 Implementation
+      Specific Behavior</a>, <a class="link" href="status.html#iso.2011.specific" title="Implementation Specific Behavior">C++
+      2011 Implementation Specific Behavior</a> and <a class="link" href="status.html#iso.2017.specific" title="Implementation Specific Behavior">C++ 2017 Implementation Specific
+      Behavior</a>.
+      This section only documents behaviour which is new in the 202a draft.
    </p></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="status.iso.tr1"></a>C++ TR1</h3></div></div></div><p>
 This table is based on the table of contents of ISO/IEC DTR 19768
 Doc No: N1836=05-0096 Date: 2005-06-24
@@ -966,7 +1329,7 @@ In this implementation the header names are prefixed by
 </p><p>
 This page describes the TR1 support in mainline GCC SVN, not in any particular
 release.
-</p><div class="table"><a id="table.tr1_status"></a><p class="title"><strong>Table 1.7. C++ TR1 Implementation Status</strong></p><div class="table-contents"><table class="table" summary="C++ TR1 Implementation Status" border="1"><colgroup><col align="left" class="c1" /><col align="left" class="c2" /><col align="left" class="c3" /><col align="left" class="c4" /></colgroup><thead><tr><th align="left">Section</th><th align="left">Description</th><th align="left">Status</th><th align="left">Comments</th></tr></thead><tbody><tr><td align="left"><span class="emphasis"><em>2</em></span></td><td colspan="3" align="left"><span class="emphasis"><em>General Utilities</em></span></td></tr><tr><td align="left">2.1</td><td align="left">Reference wrappers</td><td align="left"> </td><td align="left"> </td></tr><tr><td align="left">2.1.1</td><td align="left">Additions to header <code class="code">&lt;functional&gt;</code> synopsis</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">2.1.2</td><td align="left">Class template <code class="code">reference_wrapper</code></td><td align="left"> </td><td align="left"> </td></tr><tr><td align="left">2.1.2.1</td><td align="left"><code class="code">reference_wrapper</code> construct/copy/destroy</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">2.1.2.2</td><td align="left"><code class="code">reference_wrapper</code> assignment</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">2.1.2.3</td><td align="left"><code class="code">reference_wrapper</code> access</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">2.1.2.4</td><td align="left"><code class="code">reference_wrapper</code> invocation</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">2.1.2.5</td><td align="left"><code class="code">reference_wrapper</code> helper functions</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">2.2</td><td align="left">Smart pointers</td><td align="left"> </td><td align="left"> </td></tr><tr><td align="left">2.2.1</td><td align="left">Additions to header <code class="code">&lt;memory&gt;</code> synopsis</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">2.2.2</td><td align="left">Class <code class="code">bad_weak_ptr</code></td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">2.2.3</td><td align="left">Class template <code class="code">shared_ptr</code></td><td align="left"> </td><td align="left">
+</p><div class="table"><a id="table.tr1_status"></a><p class="title"><strong>Table 1.8. C++ TR1 Implementation Status</strong></p><div class="table-contents"><table class="table" summary="C++ TR1 Implementation Status" border="1"><colgroup><col align="left" class="c1" /><col align="left" class="c2" /><col align="left" class="c3" /><col align="left" class="c4" /></colgroup><thead><tr><th align="left">Section</th><th align="left">Description</th><th align="left">Status</th><th align="left">Comments</th></tr></thead><tbody><tr><td align="left"><span class="emphasis"><em>2</em></span></td><td colspan="3" align="left"><span class="emphasis"><em>General Utilities</em></span></td></tr><tr><td align="left">2.1</td><td align="left">Reference wrappers</td><td align="left"> </td><td align="left"> </td></tr><tr><td align="left">2.1.1</td><td align="left">Additions to header <code class="code">&lt;functional&gt;</code> synopsis</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">2.1.2</td><td align="left">Class template <code class="code">reference_wrapper</code></td><td align="left"> </td><td align="left"> </td></tr><tr><td align="left">2.1.2.1</td><td align="left"><code class="code">reference_wrapper</code> construct/copy/destroy</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">2.1.2.2</td><td align="left"><code class="code">reference_wrapper</code> assignment</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">2.1.2.3</td><td align="left"><code class="code">reference_wrapper</code> access</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">2.1.2.4</td><td align="left"><code class="code">reference_wrapper</code> invocation</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">2.1.2.5</td><td align="left"><code class="code">reference_wrapper</code> helper functions</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">2.2</td><td align="left">Smart pointers</td><td align="left"> </td><td align="left"> </td></tr><tr><td align="left">2.2.1</td><td align="left">Additions to header <code class="code">&lt;memory&gt;</code> synopsis</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">2.2.2</td><td align="left">Class <code class="code">bad_weak_ptr</code></td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">2.2.3</td><td align="left">Class template <code class="code">shared_ptr</code></td><td align="left"> </td><td align="left">
 	<p>
 	  Uses code from
 	  <a class="link" href="http://www.boost.org/libs/smart_ptr/shared_ptr.htm" target="_top">boost::shared_ptr</a>.
@@ -987,7 +1350,7 @@ decimal floating-point arithmetic
 </p><p>
 This page describes the TR 24733 support in mainline GCC SVN, not in any
 particular release.
-</p><div class="table"><a id="table.decfp_status"></a><p class="title"><strong>Table 1.8. C++ TR 24733 Implementation Status</strong></p><div class="table-contents"><table class="table" summary="C++ TR 24733 Implementation Status" border="1"><colgroup><col align="left" class="c1" /><col align="left" class="c2" /><col align="left" class="c3" /><col align="left" class="c4" /></colgroup><thead><tr><th align="left">Section</th><th align="left">Description</th><th align="left">Status</th><th align="left">Comments</th></tr></thead><tbody><tr><td align="left">
+</p><div class="table"><a id="table.decfp_status"></a><p class="title"><strong>Table 1.9. C++ TR 24733 Implementation Status</strong></p><div class="table-contents"><table class="table" summary="C++ TR 24733 Implementation Status" border="1"><colgroup><col align="left" class="c1" /><col align="left" class="c2" /><col align="left" class="c3" /><col align="left" class="c4" /></colgroup><thead><tr><th align="left">Section</th><th align="left">Description</th><th align="left">Status</th><th align="left">Comments</th></tr></thead><tbody><tr><td align="left">
 	<span class="emphasis"><em>0</em></span>
       </td><td colspan="3" align="left">
 	<span class="emphasis"><em>Introduction</em></span>
@@ -1027,7 +1390,7 @@ non-strict modes (i.e. <code class="code">-std=gnu++NN</code> modes) the
 hypergeometric functions and confluent hypergeometric functions
 from TR1 are also provided, defined in namespace
 <code class="code">__gnu_cxx</code>.
-</p><div class="table"><a id="table.specfun_status"></a><p class="title"><strong>Table 1.9. C++ Special Functions Implementation Status</strong></p><div class="table-contents"><table class="table" summary="C++ Special Functions Implementation Status" border="1"><colgroup><col align="left" class="c1" /><col align="left" class="c2" /><col align="left" class="c3" /><col align="left" class="c4" /></colgroup><thead><tr><th align="left">Section</th><th align="left">Description</th><th align="left">Status</th><th align="left">Comments</th></tr></thead><tbody><tr bgcolor="#B0B0B0"><td align="left">7</td><td align="left">Macro names</td><td align="left">Partial</td><td align="left">No diagnostic for inconsistent definitions of
+</p><div class="table"><a id="table.specfun_status"></a><p class="title"><strong>Table 1.10. C++ Special Functions Implementation Status</strong></p><div class="table-contents"><table class="table" summary="C++ Special Functions Implementation Status" border="1"><colgroup><col align="left" class="c1" /><col align="left" class="c2" /><col align="left" class="c3" /><col align="left" class="c4" /></colgroup><thead><tr><th align="left">Section</th><th align="left">Description</th><th align="left">Status</th><th align="left">Comments</th></tr></thead><tbody><tr bgcolor="#B0B0B0"><td align="left">7</td><td align="left">Macro names</td><td align="left">Partial</td><td align="left">No diagnostic for inconsistent definitions of
              <code class="code">__STDCPP_WANT_MATH_SPEC_FUNCS__</code></td></tr><tr><td align="left">8</td><td align="left">Mathematical special functions</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1</td><td align="left">Additions to header <code class="code">&lt;cmath&gt;</code> synopsis</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.1</td><td align="left">associated Laguerre polynomials</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.2</td><td align="left">associated Legendre functions</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.3</td><td align="left">beta function</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.4</td><td align="left">(complete) elliptic integral of the first kind</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.5</td><td align="left">(complete) elliptic integral of the second kind</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.6</td><td align="left">(complete) elliptic integral of the third kind</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.7</td><td align="left">regular modified cylindrical Bessel functions</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.8</td><td align="left">cylindrical Bessel functions (of the first kind)</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.9</td><td align="left">irregular modified cylindrical Bessel functions</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.10</td><td align="left">cylindrical Neumann functions</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.11</td><td align="left">(incomplete) elliptic integral of the first kind</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.12</td><td align="left">(incomplete) elliptic integral of the second kind</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.13</td><td align="left">(incomplete) elliptic integral of the third kind</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.14</td><td align="left">exponential integral</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.15</td><td align="left">Hermite polynomials</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.16</td><td align="left">Laguerre polynomials</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.17</td><td align="left">Legendre polynomials</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.18</td><td align="left">Riemann zeta function</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.19</td><td align="left">spherical Bessel functions (of the first kind)</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.20</td><td align="left">spherical associated Legendre functions</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.1.21</td><td align="left">spherical Neumann functions</td><td align="left">Y</td><td align="left"> </td></tr><tr><td align="left">8.2</td><td align="left">Additions to header <code class="code">&lt;math.h&gt;</code></td><td align="left">Y</td><td align="left"> </td></tr><tr bgcolor="#B0B0B0"><td align="left">8.3</td><td align="left">The header <code class="code">&lt;ctgmath&gt;</code></td><td align="left">Partial</td><td align="left">Conflicts with C++ 2011 requirements.</td></tr><tr bgcolor="#C8B0B0"><td align="left">8.4</td><td align="left">The header <code class="code">&lt;tgmath.h&gt;</code></td><td align="left">N</td><td align="left">Conflicts with C++ 2011 requirements.</td></tr></tbody></table></div></div><br class="table-break" /><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="iso.specfun.specific"></a>Implementation Specific Behavior</h4></div></div></div><p>For behaviour which is specified by the 2011 standard,
       see <a class="link" href="status.html#iso.2011.specific" title="Implementation Specific Behavior">C++ 2011 Implementation
       Specific Behavior</a>. This section documents behaviour which
diff --git a/libstdc++-v3/doc/xml/manual/intro.xml b/libstdc++-v3/doc/xml/manual/intro.xml
index 7159b59..28210cb 100644
--- a/libstdc++-v3/doc/xml/manual/intro.xml
+++ b/libstdc++-v3/doc/xml/manual/intro.xml
@@ -43,6 +43,10 @@
     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" parse="xml" href="status_cxx2017.xml">
     </xi:include>
 
+    <!-- Section 01.4 : Status C++ 2020 -->
+    <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" parse="xml" href="status_cxx2020.xml">
+    </xi:include>
+
     <!-- Section 01.5 : Status C++ TR1 -->
     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" parse="xml" href="status_cxxtr1.xml">
     </xi:include>
diff --git a/libstdc++-v3/doc/xml/manual/status_cxx2017.xml b/libstdc++-v3/doc/xml/manual/status_cxx2017.xml
index f379308..0af8a02 100644
--- a/libstdc++-v3/doc/xml/manual/status_cxx2017.xml
+++ b/libstdc++-v3/doc/xml/manual/status_cxx2017.xml
@@ -981,14 +981,21 @@ and test for <code>__STDCPP_MATH_SPEC_FUNCS__ >= 201003L</code>.
    </para>
 
    <para>
+      <emphasis>20.5.1.2 [headers]</emphasis>
+      Whether names from Annex K are declared by C++ headers depends on
+      whether the underlying C library supports Annex K and declares the
+      names. For the GNU C library, there is no Annex K support and so
+      none of its names are declared by C++ headers.
+   </para>
+
+   <para>
       <emphasis>23.6.5 [optional.bad_optional_access]</emphasis>
       <code>what()</code> returns <literal>"bad optional access"</literal>.
    </para>
 
    <para>
       <emphasis>23.7.3 [variant.variant]</emphasis>
-      Whether <classname>variant</classname> supports over-aligned types
-      should be documented here.
+      <classname>variant</classname> supports over-aligned types.
    </para>
 
    <para>
@@ -998,15 +1005,21 @@ and test for <code>__STDCPP_MATH_SPEC_FUNCS__ >= 201003L</code>.
 
    <para>
       <emphasis>23.12.5.2 [memory.resource.pool.options]</emphasis>
-      The limits for maximum number of blocks and largest allocation size
-      supported by <classname>pool_options</classname> should be documented
-      here.
+      Let S equal <code>numeric_limits&lt;size_t&gt;::digits</code>.
+      The limit for maximum number of blocks in a chunk is given by
+      <inlineequation><mathphrase>2<superscript>N</superscript>-1</mathphrase></inlineequation>,
+      where N is <inlineequation><mathphrase>min(19, 3 + S/2)</mathphrase></inlineequation>.
+      The largest allocation size that will be allocated from a pool is
+      <inlineequation><mathphrase>2<superscript>22</superscript></mathphrase></inlineequation>
+      when <inlineequation><mathphrase>S > 20</mathphrase></inlineequation>,
+      otherwise 3072 when <inlineequation><mathphrase>S > 16</mathphrase></inlineequation>,
+      otherwise 768.
    </para>
 
    <para>
       <emphasis>23.12.6.1 [memory.resource.monotonic.buffer.ctor]</emphasis>
-      The default <code>next_buffer_size</code> and growth factor should
-      be documented here.
+      The default <code>next_buffer_size</code> is <code>128 * sizeof(void*)</code>.
+      The default growth factor is <code>1.5</code>.
    </para>
 
    <para>
@@ -1067,13 +1080,32 @@ and test for <code>__STDCPP_MATH_SPEC_FUNCS__ >= 201003L</code>.
 
    <para>
       <emphasis>30.10.5 [fs.filesystem.syn]</emphasis>
-      The clock used for file times is
-      <classname>std::chrono::system_clock</classname>.
+      The clock used for file times is an unspecified type
+      with a signed 64-bit representation, capable of representing
+      timestamps with nanosecond resolution. The clock's epoch is
+      unspecified, but is not the same as the system clock's epoch.
    </para>
 
    <para>
       <emphasis>30.10.7.1 [fs.path.generic]</emphasis>
       dot-dot in the root-directory refers to the root-directory itself.
+      On Windows, a drive specifier such as <code>"C:"</code> or
+      <code>"z:"</code> is treated as a root-name. On Cygwin, a path
+      that begins with two successive directory separators is a
+      root-name. Otherwise (for POSIX-like systems other than Cygwin),
+      the implementation-defined root-name is an unspecified string
+      which does not appear in any pathnames.
+   </para>
+
+   <para>
+      <emphasis>30.10.10.1 [fs.enum.path.format]</emphasis>
+      The character sequence is always interpreted in the native pathname
+      format.
+   </para>
+
+   <para>
+      <emphasis>30.10.15.4 [fs.op.file_size]</emphasis>
+      If <code>!is_regular_file(p)</code>, an error is reported.
    </para>
 
 
diff --git a/libstdc++-v3/doc/xml/manual/status_cxx2020.xml b/libstdc++-v3/doc/xml/manual/status_cxx2020.xml
new file mode 100644
index 0000000..6735385
--- /dev/null
+++ b/libstdc++-v3/doc/xml/manual/status_cxx2020.xml
@@ -0,0 +1,980 @@
+<section xmlns="http://docbook.org/ns/docbook" version="5.0" 
+	 xml:id="status.iso.2020" xreflabel="Status C++ 2020">
+<?dbhtml filename="status_iso_cxx2020.html"?>
+
+<info><title>C++ 202a</title>
+  <keywordset>
+    <keyword>ISO C++</keyword>
+    <keyword>2020</keyword>
+  </keywordset>
+</info>
+
+<para>
+In this implementation the <literal>-std=gnu++2a</literal> or
+<literal>-std=c++2a</literal> flag must be used to enable language
+and library
+features. See <link linkend="manual.intro.using.flags">dialect</link>
+options. The pre-defined symbol
+<constant>__cplusplus</constant> is used to check for the
+presence of the required flag.
+</para>
+
+<para>
+This section describes the C++20 and library TS support in mainline GCC SVN,
+not in any particular release.
+</para>
+
+<para>
+The following table lists new library features that have been accepted into
+the C++2a working draft. The "Proposal" column provides a link to the
+ISO C++ committee proposal that describes the feature, while the "Status"
+column indicates the first version of GCC that contains an implementation of
+this feature (if it has been implemented).
+The "SD-6 Feature Test" column shows the corresponding macro or header from
+<link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="https://isocpp.org/std/standing-documents/sd-6-sg10-feature-test-recommendations">SD-6:
+Feature-testing recommendations for C++</link>.
+</para>
+
+<table frame="all" xml:id="table.cxx20_status">
+<title>C++ 2020 Implementation Status</title>
+
+<tgroup cols="4" align="left" colsep="0" rowsep="1">
+<colspec colname="c1"/>
+<colspec colname="c2"/>
+<colspec colname="c3"/>
+<colspec colname="c4"/>
+  <thead>
+    <row>
+      <entry>Library Feature</entry>
+      <entry>Proposal</entry>
+      <entry>Status</entry>
+      <entry>SD-6 Feature Test</entry>
+    </row>
+  </thead>
+
+  <tbody>
+
+    <row>
+      <entry>  Endian just Endian </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0463r1.html">
+	P0463R1
+	</link>
+      </entry>
+      <entry align="center"> 8.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Extending <code>make_shared</code> to Support Arrays </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0674r1.html">
+	P0674R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Floating Point Atomic </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0020r6.html">
+	P0020R6
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  C++ Synchronized Buffered Ostream </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0053r7.pdf">
+	P0053R7
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Add constexpr modifiers to functions in <code>&lt;algorithm&gt;</code> and <code>&lt;utility&gt;</code> Headers </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0202r3.html">
+	P0202R3
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  Constexpr for <code>std::complex</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0415r1.html">
+	P0415R1
+	</link>
+      </entry>
+      <entry align="center"> 9.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Make <code>std::memory_order</code> a scoped enumeration </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0439r0.html">
+	P0439R0
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  String Prefix and Suffix Checking </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0457r2.html">
+	P0457R2
+	</link>
+      </entry>
+      <entry align="center"> 9.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  Transformation Trait <code>remove_cvref</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0550r2.pdf">
+	P0550R2
+	</link>
+      </entry>
+      <entry align="center"> 9.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  <code>nodiscard</code> in the Library </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0600r1.pdf">
+	P0600R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  de-pessimize legacy algorithms with <code>std::move</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0616r0.pdf">
+	P0616R0
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  Utility to convert a pointer to a raw pointer </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0653r2.html">
+	P0653R2
+	</link>
+      </entry>
+      <entry align="center"> 8.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Atomic <code>shared_ptr</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0718r2.html">
+	P0718R2
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Deprecate POD </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0767r1.html">
+	P0767R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Library Support for the Spaceship (Comparison) Operator </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0768r1.pdf">
+	P0768R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Treating Unnecessary <code>decay</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0777r1.pdf">
+	P0777R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  <code>&lt;span&gt;</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0122r7.pdf">
+	P0122R7
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Extending chrono to Calendars and Time Zones </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0355r7.html">
+	P0355R7
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Thou Shalt Not Specialize std Function Templates! </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0551r3.pdf">
+	P0551R3
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Manipulators for C++ Synchronized Buffered Ostream </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0753r2.pdf">
+	P0753R2
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  <code>&lt;version&gt;</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0754r2.pdf">
+	P0754R2
+	</link>
+      </entry>
+      <entry align="center"> 9.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Comparing Unordered Containers </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0809r0.pdf">
+	P0809R0
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Constexpr iterator requirements </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0858r0.html">
+	P0858R0
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Symmetry for spaceship </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0905r1.html">
+	P0905R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  <code>string::reserve</code> Should Not Shrink </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0966r1.html">
+	P0966R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Atomic Ref </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0019r8.html">
+	P0019R8
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  Checking for Existence of an Element in Associative Containers </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0458r2.html">
+	P0458R2
+	</link>
+      </entry>
+      <entry align="center"> 9.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  LWG 2511: guaranteed copy elision for piecewise construction </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0475r1.html">
+	P0475R1
+	</link>
+      </entry>
+      <entry align="center"> 7.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Bit-casting object representations </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0476r2.html">
+	P0476R2
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  The Curious Case of Padding Bits, Featuring Atomic Compare-and-Exchange </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0528r3.html">
+	P0528R3
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Support for contract based programming in C++ </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0542r5.html">
+	P0542R5
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  Integral power-of-2 operations </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0556r3.html">
+	P0556R3
+	</link>
+      </entry>
+      <entry align="center"> 9.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Reviewing Deprecated Facilities of C++17 for C++20 </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0619r4.html">
+	P0619R4
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  Improving the Return Value of Erase-Like Algorithms </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0646r1.pdf">
+	P0646R1
+	</link>
+      </entry>
+      <entry align="center"> 9.1 </entry>
+      <entry> <code>__cpp_lib_list_remove_return_type &gt;= 201806L</code> </entry>
+    </row>
+
+    <row>
+      <entry>  Efficient sized delete for variable sized classes </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0722r3.html">
+	P0722R3
+	</link>
+      </entry>
+      <entry align="center"> 9.1 </entry>
+      <entry> <code>__cpp_lib_destroying_delete &gt;= 201806L</code> </entry>
+    </row>
+
+    <row>
+      <entry>  Implicit conversion traits and utility functions </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0758r1.html">
+	P0758R1
+	</link>
+      </entry>
+      <entry align="center"> 9.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  <code>fpos</code> Requirements </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0759r1.html">
+	P0759R1
+	</link>
+      </entry>
+      <entry align="center"> Note 1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Add <code>shift</code> to <code>&lt;algorithm&gt;</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0769r2.pdf">
+	P0769R2
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Standard Library Specification in a Concepts and Contracts World </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0788r3.pdf">
+	P0788R3
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Constexpr for <code>swap</code> and swap related functions </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0879r0.html">
+	P0879R0
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  The <code>identity</code> metafunction </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0887r1.pdf">
+	P0887R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  <code>explicit(bool)</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0892r2.html">
+	P0892R2
+	</link>
+      </entry>
+      <entry align="center"> Note 1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Standard Library Concepts </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0898r3.pdf">
+	P0898R3
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  Eradicating unnecessarily explicit default constructors from the standard library </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0935r0.html">
+	P0935R0
+	</link>
+      </entry>
+      <entry align="center"> 9.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  Integrating feature-test macros into the C++ WD </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0941r2.html">
+	P0941R2
+	</link>
+      </entry>
+      <entry align="center"> 5.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  <code>constexpr</code> comparison operators for <code>std::array</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1023r0.pdf">
+	P1023R0
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Update The Reference To The Unicode Standard </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1025r1.html">
+	P1025R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Consistency improvements for <code>&lt;=&gt;</code> and other comparison operators </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1120r0.html">
+	P1120R0
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  <code>unwrap_ref_decay</code> and <code>unwrap_reference</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0318r1.pdf">
+	P0318R1
+	</link>
+      </entry>
+      <entry align="center"> 9.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Simplified partial function application </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0356r5.html">
+	P0356R5
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  <code>reference_wrapper</code> for incomplete types </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0357r3.html">
+	P0357R3
+	</link>
+      </entry>
+      <entry align="center"> 9.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  <code>char8_t</code>: A type for UTF-8 characters and strings </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0482r6.html">
+	P0482R6
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Fixing <code>operator&gt;&gt;(basic_istream&amp;, CharT*)</code> (LWG 2499) </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0487r1.html">
+	P0487R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Utility functions to implement uses-allocator construction </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0591r4.pdf">
+	P0591R4
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  P0595R2 <code>std::is_constant_evaluated()</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0595r2.html">
+	P0595R2
+	</link>
+      </entry>
+      <entry align="center"> 9.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  <code>variant</code> and <code>optional</code> should propagate copy/move triviality </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0602r4.html">
+	P0602R4
+	</link>
+      </entry>
+      <entry align="center"> 8.3 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  A sane <code>variant</code> converting constructor </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0608r3.html">
+	P0608R3
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  <code>visit&lt;R&gt;</code>: Explicit Return Type for <code>visit</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0655r1.pdf">
+	P0655R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  <code>std::function</code> move constructor should be <code>noexcept</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0771r1.pdf">
+	P0771R1
+	</link>
+      </entry>
+      <entry align="center"> 7.2 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  The One Ranges Proposal </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0896r4.pdf">
+	P0896R4
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  P0899R1 - LWG 3016 is not a defect </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0899r1.html">
+	P0899R1
+	</link>
+      </entry>
+      <entry align="center"> 7.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Heterogeneous lookup for unordered containers </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0919r3.html">
+	P0919R3
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  <code>&lt;chrono&gt;</code> <code>zero()</code>, <code>min()</code>, and <code>max()</code> should be <code>noexcept</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0972r0.pdf">
+	P0972R0
+	</link>
+      </entry>
+      <entry align="center"> 9.1 </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Constexpr in <code>std::pointer_traits</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1006r1.pdf">
+	P1006R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  <code>std::assume_aligned</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1007r3.pdf">
+	P1007R3
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Smart pointer creation with default initialization </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1020r1.html">
+	P1020R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Misc constexpr bits </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1032r1.html">
+	P1032R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Should Span be Regular? </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1085r2.md">
+	P1085R2
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Editorial Guidance for merging P0019r8 and P0528r3 </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1123r0.html">
+	P1123R0
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Cleaning up Clause 20 </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1148r0.pdf">
+	P1148R0
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Make stateful allocator propagation more consistent for <code>operator+(basic_string)</code> </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1165r1.html">
+	P1165R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <entry>  Adopt Consistent Container Erasure from Library Fundamentals 2 for C++20 </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html">
+	P1209R0
+	</link>
+      </entry>
+      <entry align="center"> 9.1 </entry>
+      <entry> <code>__cpp_lib_erase_if &gt;= 201811L</code> </entry>
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Completing the Rebase of Library Fundamentals, Version 3, Working Draft </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1210r0.html">
+	P1210R0
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Alternative Wording for P0907R4 Signed Integers are Two's Complement </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1236r1.html">
+	P1236R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Remove CommonReference requirement from StrictWeakOrdering (a.k.a Fixing Relations) </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1248r1.html">
+	P1248R1
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#C8B0B0" ?>
+      <entry>  Improving Completeness Requirements for Type Traits </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1285r0.pdf">
+	P1285R0
+	</link>
+      </entry>
+      <entry align="center"> </entry>
+      <entry />
+    </row>
+
+    <row>
+      <?dbhtml bgcolor="#B0B0B0" ?>
+      <entry>  Missing feature test macros </entry>
+      <entry>
+        <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1353r0.html">
+	P1353R0
+	</link>
+      </entry>
+      <entry align="center"> Partial </entry>
+      <entry />
+    </row>
+  </tbody>
+</tgroup>
+</table>
+
+<para>
+Note 1: The changes in the proposal either do not affect the code in libstdc++,
+or the changes are not required for conformance.
+</para>
+
+
+<section xml:id="iso.2020.specific" xreflabel="Implementation Specific"><info><title>Implementation Specific Behavior</title></info>
+
+   <para>For behaviour which is also specified by previous standards,
+      see <link linkend="iso.1998.specific">C++ 1998/2003 Implementation
+      Specific Behavior</link>, <link linkend="iso.2011.specific">C++
+      2011 Implementation Specific Behavior</link> and <link
+      linkend="iso.2017.specific">C++ 2017 Implementation Specific
+      Behavior</link>.
+      This section only documents behaviour which is new in the 202a draft.
+   </para>
+
+
+</section>
+
+</section>