# in 5.005_02
$x = (1,2,3)[10];  # $x is undef
@x = (1,2,3)[10];  # @x is (), not (undef)
@x = (undef)[0];   # @x is (), not (undef)

# in 5.6.0
$x = (1,2,3)[10];  # $x is undef
@x = (1,2,3)[10];  # @x is (), not (undef)
@x = (undef)[0];   # @x is (undef), not ()