+C<pack("D", $x)> and C<pack("F", $x)> now zero the padding on x86 long
+double builds. GCC 4.8 and later, under some build options, would
+either overwrite the zero-initialized padding, or bypass the
+initialized buffer entirely. This caused F<op/pack.t> to fail. [perl
+#123971]
+
+=item *
+
+Extending an array cloned from a parent thread could result in
+"Modification of a read-only value attempted" errors when attempting
+to modify the new elements. [perl #124127]
+
+=item *
+
+An assertion failure and subsequent crash with C<< *x=<y> >> has been fixed.
+[perl #123790]
+
+=item *
+
+An optimization for state variable initialization introduced in Perl 5.21.6 has
+been reverted because it was found to exacerbate some other existing buggy
+behaviour. [perl #124160]
+
+=item *
+
+The extension of another optimization to cover more ops in Perl 5.21 has also
+been reverted to its Perl 5.20 state as a temporary fix for regression issues
+that it caused. [perl #123790]
+
+=item *
+
+New bitwise ops added in Perl 5.21.9 accidentally caused C<$^H |= 0x1c020000>
+to enable all features. This has now been fixed.
+
+=item *
+
+A possible crashing/looping bug has been fixed. [perl #124099]
+
+=item *
+
+UTF-8 variable names used in array indexes, unquoted UTF-8 HERE-document
+terminators and UTF-8 function names all now work correctly. [perl #124113]
+
+=item *
+
+Breakage in C<require(VERSION)> (with parentheses), introduced in Perl 5.21.6,
+has been fixed. [perl #124135]
+
+=item *
+
+Wide char warnings, wrongly raised in UTF-8 locales since Perl 5.21.8, are now
+suppressed. [perl #123527]
+
+=item *
+
+A subtle bug introduced in Perl 5.21.4 involving UTF-8 in regular expressions
+and sometimes causing a crash has been fixed. A new test script has been added
+to test this fix; see under L</Testing>. [perl #124109]
+
+=item *
+
+A change introduced in Perl 5.21.10 that broke the autovivification CPAN module
+has been reverted.
+
+=item *
+
+A bug whereby C<< 'FOO'->f() >> lost the read-only status of C<FOO>, introduced
+in Perl 5.21.7, has been fixed. [perl #123619]
+
+=item *
+
+A regression in Perl 5.21 in the matching of C</[A-Z]/ai> has been fixed.