do {
  my $a = { a => sub { ... }, original_a => 'fix' };
  $a->{original_a} = $a->{a};
  $a;
}

##</code><code>##

$HASH1 = {
           a      => sub {
                       use warnings;
                       use strict;
                       print "AAA\n";
                     },
           original_a
                  => 'V: $HASH1->{a}'
         };
$HASH1->{original_a} = $HASH1->{a};