Result of "Example #8 Adding the array itself as an element of it self" will be another for PHP7:

a: (refcount=2, is_ref=1)=array (
    0 => (refcount=2, is_ref=0)='one',
    1 => (refcount=2, is_ref=1)=...
)

insted of:
a: (refcount=2, is_ref=1)=array (
   0 => (refcount=1, is_ref=0)='one',
   1 => (refcount=2, is_ref=1)=...
)

Internal value representation in PHP 7:
https://nikic.github.io/2015/05/05/Internal-value-representation-in-PHP-7-part-1.html