[gcc r12-6634] libstdc++: Document final option names for enabling C++20

[Jonathan Wakely]

https://gcc.gnu.org/g:5a3dc58a1d7a792e776a59389e8901b614ce6d0d

commit r12-6634-g5a3dc58a1d7a792e776a59389e8901b614ce6d0d
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Mon Jan 17 11:26:21 2022 +0000

    libstdc++: Document final option names for enabling C++20
    
    libstdc++-v3/ChangeLog:
    
            * doc/xml/manual/status_cxx2020.xml: Use final C++20 option
            names.
            * doc/html/manual/status.html: Regenerate.

Diff:
---
 libstdc++-v3/doc/html/manual/status.html       | 4 ++--
 libstdc++-v3/doc/xml/manual/status_cxx2020.xml | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/libstdc++-v3/doc/html/manual/status.html b/libstdc++-v3/doc/html/manual/status.html
index 6c74e47e5ce..1718631138c 100644
--- a/libstdc++-v3/doc/html/manual/status.html
+++ b/libstdc++-v3/doc/html/manual/status.html
@@ -1246,8 +1246,8 @@ since C++14 and the implementation is complete.
                   vectorizable types with <code class="code">sizeof(T)</code> < 4
                 </td><td align="left">"-mavx512bw" and "-mavx512vl"</td></tr></tbody></table></div></div><p><br class="table-break" />
      </p></div></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="status.iso.2020"></a>C++ 2020</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
+In this implementation the <code class="literal">-std=gnu++20</code> or
+<code class="literal">-std=c++20</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
diff --git a/libstdc++-v3/doc/xml/manual/status_cxx2020.xml b/libstdc++-v3/doc/xml/manual/status_cxx2020.xml
index cebe36a8d5e..7e2582668ed 100644
--- a/libstdc++-v3/doc/xml/manual/status_cxx2020.xml
+++ b/libstdc++-v3/doc/xml/manual/status_cxx2020.xml
@@ -10,8 +10,8 @@
 </info>
 
 <para>
-In this implementation the <literal>-std=gnu++2a</literal> or
-<literal>-std=c++2a</literal> flag must be used to enable language
+In this implementation the <literal>-std=gnu++20</literal> or
+<literal>-std=c++20</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