1--TEST-- 2Bug #79793: Use after free if string used in undefined index warning is changed 3--FILE-- 4<?php 5 6$key = "foo"; 7$key .= "bar"; 8set_error_handler(function($_, $m) use (&$key) { 9 echo "$m\n"; 10 $key .= "baz"; 11}); 12 13$ary = []; 14$ary[$key]++; 15var_dump($ary); 16$ary[$key] += 1; 17var_dump($ary); 18 19?> 20--EXPECT-- 21Undefined index: foobar 22array(1) { 23 ["foobar"]=> 24 int(1) 25} 26Undefined index: foobarbaz 27array(2) { 28 ["foobar"]=> 29 int(1) 30 ["foobarbaz"]=> 31 int(1) 32} 33