mixed is a reserved word (not keyword!) as of PHP 8.0.0. (#938)

Author: mumumu

appendices/migration80/incompatible.xml

@@ -71,6 +71,11 @@
       <literal>match</literal> is now a reserved keyword.
      </para>
     </listitem>
+    <listitem>
+     <para>
+      <literal>mixed</literal> is now a reserved word, so it cannot be used to name a class, interface or trait, and is also prohibited from being used in namespaces.
+     </para>
+    </listitem>
     <listitem>
      <para>
       Assertion failures now throw by default. If the old behavior is desired,

appendices/reserved.xml

@@ -549,6 +549,9 @@
         <entry>
          object (as of PHP 7.2)
         </entry>
+        <entry>
+         mixed (as of PHP 8.0)
+        </entry>
        </row>
       </tbody>
      </tgroup>
@@ -569,9 +572,6 @@
         <entry>
          resource
         </entry>
-        <entry>
-         mixed
-        </entry>
         <entry>
          numeric
         </entry>