Description:
------------
Segfault in __wakeup method when unserializing object from session

Test script:
---------------
class BusinessObject {
    private $properties;
    public function __wakeup() {                                                                                                                                                                                   
        $this->properties = null;
    }
}

session content:
... s:32:"w\bo\BussinessObjectproperties";a:9:{s:6:"action";O:16:"ReflectionMethod":2:{s:4:"name";s:9:"getAction";s:5:"class";s:18:"document\test\Form";}s:14:"originalAction";O:16:"ReflectionMethod":2:{s:4:"name";s:17:"getOriginalAction";s:5:"class";s:18:"document\test\Form";}s:14:"relativeAction";O:16:"ReflectionMethod":2:{s:4:"name";s:17:"getRelativeAction";s:5:"class";s:18:"document\test\Form";}s:8:"checksum";O:16:"ReflectionMethod":2:{s:4:"name";s:11:"getChecksum";s:5:"class";s:18:"document\test\Form";}s:7:"enabled";O:16:"ReflectionMethod":2:{s:4:"name";s:10:"getEnabled";s:5:"class";s:18:"document\test\Form";}s:6:"method";O:16:"ReflectionMethod":2:{s:4:"name";s:9:"getMethod";s:5:"class";s:18:"document\test\Form";}s:4:"html";O:16:"ReflectionMethod":2:{s:4:"name";s:7:"getHtml";s:5:"class";s:18:"document\test\Form";}s:6:"params";O:16:"ReflectionMethod":2:{s:4:"name";s:9:"getParams";s:5:"class";s:18:"document\test\Form";}s:3:"_id";O:16:"ReflectionMethod":2:{s:4:"name";s:5:"getId";s:5:"class";s:22:"w\bo\mongo\MongoObject";}} ...

Expected result:
----------------
A BusinessObject instance with $properties set to NULL.

Actual result:
--------------
Program terminated with signal 11, Segmentation fault.
#0  zend_std_write_property (object=0x7f89ce1f03e0, member=<optimized out>, value=0x7f89ce1f1ed0, key=<optimized out>) at /build/buildd/php5-5.5.3+dfsg/Zend/zend_object_handlers.c:548
548	/build/buildd/php5-5.5.3+dfsg/Zend/zend_object_handlers.c: No such file or directory.
(gdb) backtrace
#0  zend_std_write_property (object=0x7f89ce1f03e0, member=<optimized out>, value=0x7f89ce1f1ed0, key=<optimized out>) at /build/buildd/php5-5.5.3+dfsg/Zend/zend_object_handlers.c:548
#1  0x00007f89c848ae88 in zend_assign_to_object (key=0x7f89ac9129e8, opcode=136, execute_data=0x7f89cca19548, value_op=<optimized out>, value_type=<optimized out>, property_name=0x7f89ac9129e8, 
    object_ptr=<optimized out>, retval=0x0) at /build/buildd/php5-5.5.3+dfsg/Zend/zend_execute.c:739
#2  ZEND_ASSIGN_OBJ_SPEC_UNUSED_CONST_HANDLER (execute_data=0x7f89cca19548) at /build/buildd/php5-5.5.3+dfsg/Zend/zend_vm_execute.h:25069
#3  0x00007f89c8430918 in execute_ex (execute_data=0x7f89cca19548) at /build/buildd/php5-5.5.3+dfsg/Zend/zend_vm_execute.h:356
#4  0x00007f89c523ad7d in xdebug_execute_ex (execute_data=0x7f89cca19548) at /build/buildd/xdebug-2.2.3/build-php5/xdebug.c:1437
#5  0x00007f89c83f9188 in zend_call_function (fci=fci@entry=0x7fff9f5502f0, fci_cache=<optimized out>, fci_cache@entry=0x0) at /build/buildd/php5-5.5.3+dfsg/Zend/zend_execute_API.c:939
#6  0x00007f89c83f937e in call_user_function_ex (function_table=<optimized out>, object_pp=object_pp@entry=0x7fff9f5504d0, function_name=function_name@entry=0x7fff9f550380, 
    retval_ptr_ptr=retval_ptr_ptr@entry=0x7fff9f550378, param_count=param_count@entry=0, params=params@entry=0x0, no_separation=no_separation@entry=1, symbol_table=symbol_table@entry=0x0)
    at /build/buildd/php5-5.5.3+dfsg/Zend/zend_execute_API.c:727
#7  0x00007f89c817eced in object_common2 (rval=0x7fff9f5504d0, p=0x7fff9f550600, max=<optimized out>, var_hash=0x7fff9f550610, elements=15) at /build/buildd/php5-5.5.3+dfsg/ext/standard/var_unserializer.c:393
#8  0x00007f89c8379d4a in php_var_unserialize (rval=rval@entry=0x7fff9f5504d0, p=p@entry=0x7fff9f550600, max=max@entry=0x7f89ce1dcd6c "", var_hash=var_hash@entry=0x7fff9f550610)
    at /build/buildd/php5-5.5.3+dfsg/ext/standard/var_unserializer.c:740
#9  0x00007f89c817e8dc in process_nested_data (p=p@entry=0x7fff9f550600, max=max@entry=0x7f89ce1dcd6c "", var_hash=var_hash@entry=0x7fff9f550610, ht=0x7f89ce1e2190, elements=1, elements@entry=3, 
    objprops=objprops@entry=0, rval=0x7fff9f550608) at /build/buildd/php5-5.5.3+dfsg/ext/standard/var_unserializer.c:286
#10 0x00007f89c8379a94 in php_var_unserialize (rval=rval@entry=0x7fff9f550608, p=p@entry=0x7fff9f550600, max=max@entry=0x7f89ce1dcd6c "", var_hash=var_hash@entry=0x7fff9f550610)
    at /build/buildd/php5-5.5.3+dfsg/ext/standard/var_unserializer.c:776
#11 0x00007f89c82a344d in ps_srlzr_decode_php (val=<optimized out>, vallen=<optimized out>) at /build/buildd/php5-5.5.3+dfsg/ext/session/session.c:992
#12 0x00007f89c82a210a in php_session_decode (val=<optimized out>, vallen=<optimized out>) at /build/buildd/php5-5.5.3+dfsg/ext/session/session.c:224
#13 0x00007f89c82a599c in php_session_initialize () at /build/buildd/php5-5.5.3+dfsg/ext/session/session.c:508
#14 0x00007f89c82a6135 in php_session_start () at /build/buildd/php5-5.5.3+dfsg/ext/session/session.c:1503
#15 0x00007f89c82a7079 in zif_session_start (ht=<optimized out>, return_value=0x7f89ce298ed8, return_value_ptr=<optimized out>, this_ptr=<optimized out>, return_value_used=<optimized out>)
    at /build/buildd/php5-5.5.3+dfsg/ext/session/session.c:1963