message: avoid printing 'void void'
diff: @@ -35,8 +35,10 @@ void Value::fixupTypes(const Model &m) {
  ostream& operator<<(ostream &os, const Value &val) {
  auto t = val.getType().toString();
  if (!t.empty())
  - os << t << ' ';
  - return os << val.getName();
  + os << t;
  + if (!dynamic_cast<VoidType*>(&val.getType()))
  + os << ' ' << val.getName();
  + return os;
  }
  