Description:
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Segmentation fault when trying to get the current from an invalid iterator

Test script:
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$arr = [1,3,55,66,43,6];

$iter = new NoRewindIterator(new ArrayIterator($arr));

while($iter->valid()) {
    $iter->next();
}

var_dump($iter->current()); //Segmentation fault: 11 here!

Actual result:
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Segmentation fault: 11