[php-src] Issue #12826: Weird pointers issue in nested loops

Issue: https://github.com/php/php-src/issues/12826 Author: bloatware ### Description Hi, I observe a weird issue in php 8.3.0 with the following (weird) code: ```php <?php $test = array( 'a' => 1, 'b' => 2, 'c' => 3, 'd' => 4, ); //unset($test['a']); //unset($test['b']); //unset($test['c']); //unset($test['d']); foreach($test as $k => &$v) { // Mind the reference! echo "Pass $k : "; foreach($test as $kk => $vv) { echo $test[$kk]; if ($kk == $k) $test[$kk] = 0; } echo '<br />'; } unset($v); ``` As expected, it outputs: ``` Pass a : 1234 Pass b : 0234 Pass c : 0034 Pass d : 0004 ``` But if I unset, say $test['a'] and $test['b'] before the loop, the server seems to enter some kind of infinite loop. Unsetting only *one* element or only few *last* elements does not seem to yield any problem. When looping by value $k => $v everything is fine of course. The problem seems to come from $test[$kk] = 0 assignment. If I comment it out, everything is fine again, whichever elements are unset. I've tested it on few servers, with the same result. The code works without any issue in php from 5.4 to 8.2. ### PHP Version PHP 8.3.0 ### Operating System Various