For state vars, C<SVs_PADSTALE> is overloaded to mean 'not yet initialised',
but this internal state is stored in a separate pad entry.
+=for apidoc Amnh||SVs_PADSTALE
+
=for apidoc AmnxU|PADNAMELIST *|PL_comppad_name
During compilation, this points to the array containing the names part
included. If the first argument is neither a CV nor a GV, this flag is
ignored (subject to change).
+=for apidoc Amnh||CV_NAME_NOTQUAL
+
=cut
*/
the outer pad name that this one mirrors. The returned pad name has the
C<PADNAMEt_OUTER> flag already set.
+=for apidoc Amnh||PADNAMEt_OUTER
+
=cut
*/