[gcc r11-9449] libstdc++: Update default -std option in manual

[Jonathan Wakely <redi@gcc.gnu.org>]

https://gcc.gnu.org/g:702d2c9febe19b95a22e93bc2c82aeedb40d4d16

commit r11-9449-g702d2c9febe19b95a22e93bc2c82aeedb40d4d16
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Mon Jan 10 11:23:12 2022 +0000

    libstdc++: Update default -std option in manual
    
    libstdc++-v3/ChangeLog:
    
            * doc/xml/manual/using.xml: Update documentation around default
            -std option.
            * doc/html/*: Regenerate.
    
    (cherry picked from commit e1b8a91e470358261862e44d23b16eee2203ef92)

Diff:
---
 libstdc++-v3/doc/html/manual/using.html | 3 ++-
 libstdc++-v3/doc/xml/manual/using.xml   | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/libstdc++-v3/doc/html/manual/using.html b/libstdc++-v3/doc/html/manual/using.html
index 140896b1f60..641a08c688b 100644
--- a/libstdc++-v3/doc/html/manual/using.html
+++ b/libstdc++-v3/doc/html/manual/using.html
@@ -11,7 +11,8 @@
       The standard library conforms to the dialect of C++ specified by the
       <code class="option">-std</code> option passed to the compiler.
       By default, <span class="command"><strong>g++</strong></span> is equivalent to
-      <span class="command"><strong>g++ -std=gnu++14</strong></span> since GCC 6, and
+      <span class="command"><strong>g++ -std=gnu++17</strong></span> since GCC 11, and
+      <span class="command"><strong>g++ -std=gnu++14</strong></span> in GCC 6, 7, 8, 9, and 10, and
       <span class="command"><strong>g++ -std=gnu++98</strong></span> for older releases.
     </p><div class="table"><a id="table.cmd_options"></a><p class="title"><strong>Table 3.1. C++ Command Options</strong></p><div class="table-contents"><table class="table" summary="C++ Command Options" border="1"><colgroup><col align="left" class="c1" /><col align="left" class="c2" /></colgroup><thead><tr><th align="left">Option Flags</th><th align="left">Description</th></tr></thead><tbody><tr><td align="left"><code class="literal">-std=c++98</code> or <code class="literal">-std=c++03</code>
       </td><td align="left">Use the 1998 ISO C++ standard plus amendments.</td></tr><tr><td align="left"><code class="literal">-std=gnu++98</code> or <code class="literal">-std=gnu++03</code>
diff --git a/libstdc++-v3/doc/xml/manual/using.xml b/libstdc++-v3/doc/xml/manual/using.xml
index 24543e9526e..ff22e509aa8 100644
--- a/libstdc++-v3/doc/xml/manual/using.xml
+++ b/libstdc++-v3/doc/xml/manual/using.xml
@@ -16,7 +16,8 @@
       The standard library conforms to the dialect of C++ specified by the
       <option>-std</option> option passed to the compiler.
       By default, <command>g++</command> is equivalent to
-      <command>g++ -std=gnu++14</command> since GCC 6, and
+      <command>g++ -std=gnu++17</command> since GCC 11, and
+      <command>g++ -std=gnu++14</command> in GCC 6, 7, 8, 9, and 10, and
       <command>g++ -std=gnu++98</command> for older releases.
     </para>