<?php
// Adapted from last example on http://nikic.github.io/2015/05/05/Internal-value-representation-in-PHP-7-part-1
$a = array(); // $a -> zend_array_1(refcount=1, value=[])
$b = $a; // $a, $b, -> zend_array_1(refcount=2, value=[])
$c = $b; // $a, $b, $c -> zend_array_1(refcount=3, value=[])
$x = $c; // $a, $b, $c, $x -> zend_array_1(refcount=4, value=[])
$d =& $c;
$y =& $d; // $a, $b, $x -> zend_array_1(refcount=4, value=[])
// $c, $d, $y -> zend_reference_1(refcount=3) ---^
echo "Before\n";
debug_zval_dump($a);
debug_zval_dump($b);
debug_zval_dump($c);
debug_zval_dump($d);
$d[] = 1; // $a, $b, $x -> zend_array_1(refcount=3, value=[])
// $c, $d, $y -> zend_reference_1(refcount=3) -> zend_array_2(refcount=1, value=[1])
echo "After\n";
debug_zval_dump($a);
debug_zval_dump($b);
debug_zval_dump($c);
debug_zval_dump($d);
- Output for 8.4.1 - 8.4.12
- Before
array(0) interned {
}
array(0) interned {
}
array(0) interned {
}
array(0) interned {
}
After
array(0) interned {
}
array(0) interned {
}
array(1) packed refcount(2){
[0]=>
int(1)
}
array(1) packed refcount(2){
[0]=>
int(1)
}
- Output for 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25
- Before
array(0) interned {
}
array(0) interned {
}
array(0) interned {
}
array(0) interned {
}
After
array(0) interned {
}
array(0) interned {
}
array(1) refcount(2){
[0]=>
int(1)
}
array(1) refcount(2){
[0]=>
int(1)
}
- Output for 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30
- Before
array(0) refcount(1){
}
array(0) refcount(1){
}
array(0) refcount(1){
}
array(0) refcount(1){
}
After
array(0) refcount(1){
}
array(0) refcount(1){
}
array(1) refcount(2){
[0]=>
int(1)
}
array(1) refcount(2){
[0]=>
int(1)
}
- Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.33
- Before
array(0) refcount(6){
}
array(0) refcount(6){
}
array(0) refcount(6){
}
array(0) refcount(6){
}
After
array(0) refcount(5){
}
array(0) refcount(5){
}
array(1) refcount(2){
[0]=>
int(1)
}
array(1) refcount(2){
[0]=>
int(1)
}
- Output for 7.0.0 - 7.0.33
- Before
array(0) refcount(5){
}
array(0) refcount(5){
}
array(0) refcount(5){
}
array(0) refcount(5){
}
After
array(0) refcount(4){
}
array(0) refcount(4){
}
array(1) refcount(2){
[0]=>
int(1)
}
array(1) refcount(2){
[0]=>
int(1)
}
- Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40
- Before
array(0) refcount(4){
}
array(0) refcount(4){
}
array(0) refcount(1){
}
array(0) refcount(1){
}
After
array(0) refcount(4){
}
array(0) refcount(4){
}
array(1) refcount(1){
[0]=>
long(1) refcount(2)
}
array(1) refcount(1){
[0]=>
long(1) refcount(2)
}
preferences:
151.51 ms | 416 KiB | 5 Q