#fixed code
                              private void escapeParameters(MustDef output) {
    for (Iterator<Var> i = jsScope.getVars(); i.hasNext();) {
      Var v = i.next();
      if (isParameter(v)) {
        // Assume we no longer know where the parameter comes from
        // anymore.
        output.reachingDef.put(v, null);
      }
    }

    // Also, assume we no longer know anything that depends on a parameter.
    for (Entry<Var, Definition> pair: output.reachingDef.entrySet()) {
      Definition value = pair.getValue();
      if (value == null) {
        continue;
      }
      for (Var dep : value.depends) {
        if (isParameter(dep)) {
          output.reachingDef.put(pair.getKey(), null);
        }
      }
    }
  }
#vulnerable code 
                              private void escapeParameters(MustDef output) {
    for (Iterator<Var> i = jsScope.getVars(); i.hasNext();) {
      Var v = i.next();
      if (v.getParentNode().getType() == Token.LP) {
        // Assume we no longer know where the parameter comes from
        // anymore.
        output.reachingDef.put(v, null);
      }
    }
  } 
                            #location 4 
                            #vulnerability type NULL_DEREFERENCE