Bug #69873 [NEW]: Weird behavior with serialize(debug_backtrace()) and __sleep

From: ftdysa at gmail dot com Operating system: Debian 6.0.10 PHP version: 5.6.10 Package: Class/Object related Bug Type: Bug Bug description:Weird behavior with serialize(debug_backtrace()) and __sleep Description: ------------ I am seeing weird behavior that I believe was introduced by this patch: https://bugs.php.net/bug.php?id=69210 It seems that if you call serialize(debug_backtrace()) where the backtrace contains an object with a __sleep method that returns a non-string (in this case, an array containing a member variable of that object), the member variable is overridden with the __toString representation of that object. That's a bit confusing to understand but I hope my example code will illustrate it better. Test script: --------------- <?php class Obj { public function __construct($mix) { foreach ($mix as $k => $v) { $this->$k = $v; } } public function __toString() { $str = ''; foreach ($this as $k => $v) { $str = "$k => $v\n"; } return $str; } } class A { public $obj; public function setObj($obj) { $this->obj = $obj; } public function getObj() { return $this->obj; } function __sleep() { return ['test' => $this->obj]; } } function printA(A $a) { var_dump($a); serialize(debug_backtrace(0)); } $obj = new Obj(['hello'=>'there']); $a = new A(); $a->setObj($obj); var_dump($a->getObj()); printA($a); var_dump($a->getObj()); Expected result: ---------------- object(Obj)#1 (1) { ["hello"]=> string(5) "there" } object(A)#2 (1) { ["obj"]=> object(Obj)#1 (1) { ["hello"]=> string(5) "there" } } object(Obj)#1 (1) { ["hello"]=> string(5) "there" } Actual result: -------------- object(Obj)#1 (1) { ["hello"]=> string(5) "there" } object(A)#2 (1) { ["obj"]=> object(Obj)#1 (1) { ["hello"]=> string(5) "there" } } string(15) "hello => there" -- Edit bug report at https://bugs.php.net/bug.php?id=69873&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=69873&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=69873&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=69873&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=69873&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=69873&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=69873&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=69873&r=needscript Try newer version: https://bugs.php.net/fix.php?id=69873&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=69873&r=support Expected behavior: https://bugs.php.net/fix.php?id=69873&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=69873&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=69873&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=69873&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=69873&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=69873&r=dst IIS Stability: https://bugs.php.net/fix.php?id=69873&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=69873&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=69873&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=69873&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=69873&r=mysqlcfg