a C<return> statement; the code was left in place. Now the code supporting
what C<study> used to do has been removed.
+=item *
+
+Under threaded perls, there is no longer a separate PV allocated for every
+COP to store its package name (C<< cop->stashpv >>). Instead, there is an
+offset (C<< cop->stashoff >>) into the new C<PL_stashpad> array, which
+holds stash pointers.
+
=back
=head1 Selected Bug Fixes