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run code in 200+ php & hhvm versions
Bugs & Features
<?php function tester( array &$error ) { $error = [ 'text' => 'nothing found' ]; return true; } $e = null; $error = []; $error[] =& $e; call_user_func( 'tester', $error ); var_dump( $error );
based on WDqL6
Output for 5.5.0 - 7.3.1
Warning: Parameter 1 to tester() expected to be a reference, value given in /in/84v2o on line 12 array(1) { [0]=> &NULL }