Description:
------------
When assigning class variables to the results of a foreach  
loop and using the variables inside the loop, I am getting  
a segfault in 5.1RC3.  
 
The problem occurs for class variables only. When doing the 
same with local variables, it does not crash. It also does 
not crash if the $this->vars["one"] is not used inside the 
foreach loop.  
 
If the foreach loop is used without setting the key for the 
result it also won't crash, e.g.: 
foreach $foo as $this->vars["two"]  
instead of  
foreach $foo as $this->vars["one"]=>$this->vars["two"] 
won't crash. 
 
I know code like this should never be written but Smarty 
actually does a lot of stuff like this so it won't work 
with 5.1.0RC3. 
 

Reproduce code:
---------------
class x
{
  function run()
  {
    $foo=array("0","1");
    foreach ($foo as $this->vars["one"]=>$this->vars["two"])
      var_dump($this->vars["one"]);
  }
}

$x=new x;
$x->run();

Expected result:
----------------
in PHP 5.1.0b3:  
int(0)  
int(1) 

Actual result:
--------------
in PHP 5.1.0RC3:  
int(0) 
NULL 
Speicherzugriffsfehler (segmentation fault)