[PATCH] wwwdocs: Two patches committed to gcc-10 release notes

[Jonathan Wakely <jwakely at redhat dot com>]

I've pushed these to wwwdocs.

commit b1bd21c81af3bc3098fca4293af164a6c6a4544a
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Fri Jan 24 15:30:06 2020 +0000

    Make it clear C++2a support is experimental

diff --git a/htdocs/gcc-10/changes.html b/htdocs/gcc-10/changes.html
index ef27c9bb..dcce6b86 100644
--- a/htdocs/gcc-10/changes.html
+++ b/htdocs/gcc-10/changes.html
@@ -331,7 +331,7 @@ a work-in-progress.</p>
 
 <h4 id="libstdcxx">Runtime Library (libstdc++)</h4>
 <ul>
-  <li>Improved C++2a support, including:
+  <li>Improved experimental C++2a support, including:
     <ul>
       <li> <code>std::span</code> (thanks to JeanHeyd Meneide). </li>
       <li>

commit 8fdda0b261bcd59e3bed41228fe9ced40ad1397f
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Fri Jan 24 15:29:46 2020 +0000

    Document C++ header reorganisation

diff --git a/htdocs/gcc-10/porting_to.html b/htdocs/gcc-10/porting_to.html
index 7d45a962..980d3af1 100644
--- a/htdocs/gcc-10/porting_to.html
+++ b/htdocs/gcc-10/porting_to.html
@@ -49,6 +49,26 @@ and provide solutions. Let us know if you have suggestions for improvements!
       extern int y;  // correct declaration in a header file
   </code></pre>
 
+
+<h2 id="cxx">C++ language issues</h2>
+
+<h3 id="header-dep-changes">Header dependency changes</h3>
+
+<p>Some C++ Standard Library headers have been changed to no longer include
+the <code>&lt;stdexcept&gt;</code> header.
+As such, C++ programs that used components defined in
+<code>&lt;stdexcept&gt;</code> or <code>&lt;string&gt;</code> without
+explicitly including the right headers will no longer compile.
+</p>
+<p>
+Previously components such as <code>std::runtime_error</code>,
+<code>std::string</code> and <code>std::allocator</code>
+were implicitly defined after including unrelated headers such as
+<code>&lt;array&gt;</code> and <code>&lt;optional&gt;</code>.
+Correct code should include the appropriate headers for the classes being used.
+</p>
+
+
 <h2 id="fortran">Fortran language issues</h2>
 
 <h3 id="argument-mismatch">Argument mismatches</h3>