Description:
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I'm using xpath to retrieve a child node from an xml structure, then loop over subelements of this node. This crashes reproducibly at the foreach loop (apache log file: child process exited with status 3221225477 -- Restarting)
Same happens with latest 5.0.3RC2

Reproduce code:
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$step = 'FindThisNode';

$node = $xml->xpath('ListOfRepositoryWorkflowProcess/RepositoryWorkflowProcess/ListOfRepositoryWfStep/RepositoryWfStep[Name3="'.$step.'"]');

print_r($node);

# crash here!
foreach ($node->ListOfRepositoryWfStepIOArgument->RepositoryWfStepIOArgument as $wfArg)
{
}


Expected result:
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no crash?!