[gcc r8-10848] libstdc++: Document when C++11/14/17 support became stable [PR 99058]

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

https://gcc.gnu.org/g:07b4b069b34262b77e4295e57351bad49f3c4d06

commit r8-10848-g07b4b069b34262b77e4295e57351bad49f3c4d06
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Thu Feb 11 15:35:23 2021 +0000

    libstdc++: Document when C++11/14/17 support became stable [PR 99058]
    
    libstdc++-v3/ChangeLog:
    
            PR libstdc++/99058
            * doc/xml/manual/status_cxx2011.xml: Document when support
            became stable.
            * doc/xml/manual/status_cxx2014.xml: Likewise.
            * doc/xml/manual/status_cxx2017.xml: Likewise.
            * doc/html/manual/status.html: Regenerate.
    
    (cherry picked from commit ce43c906049b828c0472d8499b52ac6233c869d0)

Diff:
---
 libstdc++-v3/doc/html/manual/status.html       | 8 ++++++++
 libstdc++-v3/doc/xml/manual/status_cxx2011.xml | 3 +++
 libstdc++-v3/doc/xml/manual/status_cxx2014.xml | 3 +++
 libstdc++-v3/doc/xml/manual/status_cxx2017.xml | 2 ++
 4 files changed, 16 insertions(+)

diff --git a/libstdc++-v3/doc/html/manual/status.html b/libstdc++-v3/doc/html/manual/status.html
index 189b4e5eda2..ce10dd6c108 100644
--- a/libstdc++-v3/doc/html/manual/status.html
+++ b/libstdc++-v3/doc/html/manual/status.html
@@ -153,6 +153,9 @@ features. See <a class="link" href="using.html#manual.intro.using.flags" title="
 options. The pre-defined symbol
 <code class="constant">__cplusplus</code> is used to check for the
 presence of the required flag.
+GCC 5.1 was the first release with non-experimental C++11 support,
+so the API and ABI of features added in C++11 is only stable
+since that release.
 </p><p>
 This page describes the C++11 support in the GCC 8 series.
 </p><div class="table"><a id="table.cxx11_status"></a><p class="title"><strong>Table 1.2. C++ 2011 Implementation Status</strong></p><div class="table-contents"><table class="table" summary="C++ 2011 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">
@@ -385,6 +388,9 @@ features. See <a class="link" href="using.html#manual.intro.using.flags" title="
 options. The pre-defined symbol
 <code class="constant">__cplusplus</code> is used to check for the
 presence of the required flag.
+GCC 6.1 was the first release with non-experimental C++14 support,
+so the API and ABI of features added in C++14 is only stable
+since that release.
 </p><p>
 This page describes the C++14 and library TS support in the GCC 8 series.
 </p><div class="table"><a id="table.cxx14_status"></a><p class="title"><strong>Table 1.3. C++ 2014 Implementation Status</strong></p><div class="table-contents"><table class="table" summary="C++ 2014 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">Paper</th><th align="left">Title</th><th align="left">Status</th><th align="left">Comments</th></tr></thead><tbody><tr><td align="left">
@@ -519,6 +525,8 @@ features. See <a class="link" href="using.html#manual.intro.using.flags" title="
 options. The pre-defined symbol
 <code class="constant">__cplusplus</code> is used to check for the
 presence of the required flag.
+C++17 support is experimental up to and including the GCC 8 series,
+so the API and ABI of features added in C++17 is not stable in those releases.
 </p><p>
 This section describes the C++17 and library TS support in the GCC 8 series.
 </p><p>
diff --git a/libstdc++-v3/doc/xml/manual/status_cxx2011.xml b/libstdc++-v3/doc/xml/manual/status_cxx2011.xml
index fd07f574ecb..466699e605c 100644
--- a/libstdc++-v3/doc/xml/manual/status_cxx2011.xml
+++ b/libstdc++-v3/doc/xml/manual/status_cxx2011.xml
@@ -24,6 +24,9 @@ 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.
+GCC 5.1 was the first release with non-experimental C++11 support,
+so the API and ABI of features added in C++11 is only stable
+since that release.
 </para>
 
 <para>
diff --git a/libstdc++-v3/doc/xml/manual/status_cxx2014.xml b/libstdc++-v3/doc/xml/manual/status_cxx2014.xml
index ee0836ee8ef..131e67b700f 100644
--- a/libstdc++-v3/doc/xml/manual/status_cxx2014.xml
+++ b/libstdc++-v3/doc/xml/manual/status_cxx2014.xml
@@ -17,6 +17,9 @@ 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.
+GCC 6.1 was the first release with non-experimental C++14 support,
+so the API and ABI of features added in C++14 is only stable
+since that release.
 </para>
 
 <para>
diff --git a/libstdc++-v3/doc/xml/manual/status_cxx2017.xml b/libstdc++-v3/doc/xml/manual/status_cxx2017.xml
index 3931a7a71f9..49ecc8df8b4 100644
--- a/libstdc++-v3/doc/xml/manual/status_cxx2017.xml
+++ b/libstdc++-v3/doc/xml/manual/status_cxx2017.xml
@@ -17,6 +17,8 @@ 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.
+C++17 support is experimental up to and including the GCC 8 series,
+so the API and ABI of features added in C++17 is not stable in those releases.
 </para>
 
 <para>