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run code in 150+ php & hhvm versions
Bugs & Features
<?php $a = 1; a($a); function a($a){ echo debug_zval_dump($a);//为何$a的refcount是4而不是3呢? }
Output for 7.0.0 - 7.1.0
int(1)
Output for hhvm-3.10.0 - 3.13.2
long(1) refcount(1)
Output for 4.3.0 - 5.6.28
long(1) refcount(4)