Description:
------------
With PHP 5.5.5 when I call

php > strtr("a", array("a" => "b", "c" => new stdclass));

I get

PHP Catchable fatal error:  Object of class stdClass could not be converted to string in php shell code on line 1

This used to work with PHP 5.4 and there is no reason why it shouldn't work now (haystack does not contain "c", so variable with appropriate key should not be used anyway).

Test script:
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strtr("a", array("a" => "b", "c" => new stdclass));

Expected result:
----------------
No error

Actual result:
--------------
PHP Catchable fatal error:  Object of class stdClass could not be converted to string in php shell code on line 1