[committed] libstdc++: Update C++20 status documentation

[Jonathan Wakely via Gcc-patches]

libstdc++-v3/ChangeLog:

        * doc/xml/manual/evolution.xml: Document some API changes
        and deprecations.
        * doc/xml/manual/intro.xml: Document LWG 2499.
        * doc/xml/manual/status_cxx2020.xml: Update status.
        * doc/html/*: Regenerate.

Committed to trunk.


commit 0e0beddd7fb4c0d2157c7f0c7d3f39e9533bb323
Author: Jonathan Wakely <jwak...@redhat.com>
Date:   Tue Oct 13 17:40:43 2020

    libstdc++: Update C++20 status documentation
    
    libstdc++-v3/ChangeLog:
    
            * doc/xml/manual/evolution.xml: Document some API changes
            and deprecations.
            * doc/xml/manual/intro.xml: Document LWG 2499.
            * doc/xml/manual/status_cxx2020.xml: Update status.
            * doc/html/*: Regenerate.

diff --git a/libstdc++-v3/doc/xml/manual/evolution.xml 
b/libstdc++-v3/doc/xml/manual/evolution.xml
index 625202b9a06..38f11b0300d 100644
--- a/libstdc++-v3/doc/xml/manual/evolution.xml
+++ b/libstdc++-v3/doc/xml/manual/evolution.xml
@@ -972,6 +972,42 @@ now defaults to zero.
   be used instead.
 </para>
 
+<para>
+  Experimental C++2a support improved, with new headers
+  <filename class="headerfile">&lt;concepts&gt;</filename>,
+  <filename class="headerfile">&lt;ranges&gt;</filename>,
+  <filename class="headerfile">&lt;compare&gt;</filename>,
+  <filename class="headerfile">&lt;coroutine&gt;</filename>,
+  <filename class="headerfile">&lt;numbers&gt;</filename>,
+  <filename class="headerfile">&lt;span&gt;</filename>,
+  and
+  <filename class="headerfile">&lt;stop_token&gt;</filename>
+  added.
+</para>
+
+</section>
+
+<section 
xml:id="api.rel_111"><info><title><constant>11</constant></title></info>
+
+<para>
+  The <option>--enable-cheaders=c_std</option> configuration
+  was deprecated.
+</para>
+
+<para>
+  When compiling as C++20, the <function>operator&gt;&gt;</function> overloads
+  for extracting strings into character buffers only work with arrays,
+  not raw pointers.
+</para>
+
+<para>
+  <code>std::string::reserve(n)</code> will no longer reduce
+  the string's capacity.
+  Calling <function>reserve()</function> with no arguments is equivalent
+  to <function>shrink_to_fit()</function>, but is deprecated.
+  <function>shrink_to_fit()</function> should be used instead.
+</para>
+
 </section>
 
 </section>
diff --git a/libstdc++-v3/doc/xml/manual/intro.xml 
b/libstdc++-v3/doc/xml/manual/intro.xml
index 76e55980324..3e7843f58c1 100644
--- a/libstdc++-v3/doc/xml/manual/intro.xml
+++ b/libstdc++-v3/doc/xml/manual/intro.xml
@@ -1140,6 +1140,14 @@ requirements of the license of GCC.
     ill-formed.
     </para></listitem></varlistentry>
 
+    <varlistentry xml:id="manual.bugs.dr2499"><term><link 
xmlns:xlink="http://www.w3.org/1999/xlink"; xlink:href="&DR;#2499">2499</link>:
+       <emphasis><code>operator>>(basic_istream&amp;, CharT*)</code> makes it 
hard to avoid buffer overflows
+       </emphasis>
+    </term>
+    <listitem><para>Replace <code>operator>>(basic_istream&amp;, CharT*)</code>
+     and other overloads writing through pointers.
+    </para></listitem></varlistentry>
+
     <varlistentry xml:id="manual.bugs.dr2537"><term><link 
xmlns:xlink="http://www.w3.org/1999/xlink"; xlink:href="&DR;#2537">2537</link>:
        <emphasis>Constructors for <code>priority_queue</code> taking allocators
         should call <code>make_heap</code>
diff --git a/libstdc++-v3/doc/xml/manual/status_cxx2020.xml 
b/libstdc++-v3/doc/xml/manual/status_cxx2020.xml
index b9ad03c720f..e633365ab40 100644
--- a/libstdc++-v3/doc/xml/manual/status_cxx2020.xml
+++ b/libstdc++-v3/doc/xml/manual/status_cxx2020.xml
@@ -1086,7 +1086,6 @@ or any notes about the implementation.
     </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";>
@@ -1168,13 +1167,12 @@ or any notes about the implementation.
     </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 align="center"> 11.1 </entry>
       <entry />
     </row>