<?php
class A {
 function __destruct() {
 highlight_string("<?php", true);
 trigger_error("");
 ob_start(function () use (&$c) { $c = new A; return '/'; }, 1);
 $c = new A;
 unset($c);
 ob_start(function &() use (&$c) { $c = new A; return '/'; }, 1);
 }
}
new A;

/php: /path/to/php-src/ext/standard/basic_functions.c:1837: zif_highlight_string: Assertion `zval_get_type(&(*(return_value))) == 6' failed.
Aborted

./configure --enable-debug --enable-address-sanitizer --disable-shared --with-pic --enable-mbstring --with-zlib

PHP 8.6.0-dev (cli) (built: Jan 11 2026 13:54:51) (NTS DEBUG)
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