clear is not a static function, is it right usage here?

[AsilenceBTF]

llvm-project/llvm/include/llvm/Support/CommandLine.h

Line 1863 in 23433a9

void setDefault() override { bits_storage<DataType, Storage>::clear(); }

class bits_storage {
public:
  template <class T> void addValue(const T &V) { Bits |= Bit(V); }

  unsigned getBits() { return Bits; }

  void clear() { Bits = 0; }
}
 ......
 void setDefault() override { bits_storage<DataType, Storage>::clear(); }