return absl::OkStatus();
  }

  // We may need to allocate zero inputs for trainable dtypes we don't have JVPs
  // for. Make sure they get cleaned up.
  std::vector<Gradient*> new_zeros;
  auto delete_new_zeros = gtl::MakeCleanup([&new_zeros, this] {
    for (Gradient* tensor : new_zeros) {
      this->vspace_.DeleteGradient(tensor);
    }
  });
  std::vector<Gradient*> in_grads;

  public void testShort() {
    Sink sink = new Sink(4);
    sink.putShort((short) 0x0201);
    HashCode unused = sink.hash();
    sink.assertInvariants(2);
    sink.assertBytes(new byte[] {1, 2, 0, 0}); // padded with zeros
  }

  public void testInt() {
    Sink sink = new Sink(4);
    sink.putInt(0x04030201);
    HashCode unused = sink.hash();
    sink.assertInvariants(4);
    sink.assertBytes(new byte[] {1, 2, 3, 4});
  }

  public void testShort() {
    Sink sink = new Sink(4);
    sink.putShort((short) 0x0201);
    HashCode unused = sink.hash();
    sink.assertInvariants(2);
    sink.assertBytes(new byte[] {1, 2, 0, 0}); // padded with zeros
  }

  public void testInt() {
    Sink sink = new Sink(4);
    sink.putInt(0x04030201);
    HashCode unused = sink.hash();
    sink.assertInvariants(4);
    sink.assertBytes(new byte[] {1, 2, 3, 4});
  }

		if _, err := io.ReadFull(tr.r, tr.blk[:]); err != nil {
			return nil, nil, err // EOF is okay here; exactly 1 block of zeros read
		}
		if bytes.Equal(tr.blk[:], zeroBlock[:]) {
			return nil, nil, io.EOF // normal EOF; exactly 2 block of zeros read
		}
		return nil, nil, ErrHeader // Zero block and then non-zero block
	}

	// Verify the header matches a known format.
	format := tr.blk.getFormat()

			got := string(readBuf[:n])
			if err != nil || got != want {
				t.Errorf("off %d, size %d = %v, %v (%q); want %q", off, size, n, err, got, want)
			}
		}
	}

}

type zeros struct{}

func (zeros) Read(p []byte) (int, error) {
	clear(p)
	return len(p), nil

// An IP address can be represented in different formats, to guarantee the uniqueness of the IP,
// the name of the object is the IP address in canonical format, four decimal digits separated
// by dots suppressing leading zeros for IPv4 and the representation defined by RFC 5952 for IPv6.
// Valid: 192.168.1.5 or 2001:db8::1 or 2001:db8:aaaa:bbbb:cccc:dddd:eeee:1
// Invalid: 10.01.2.3 or 2001:db8:0:0:0::1
message IPAddress {

  static long load64Safely(byte[] input, int offset, int length) {
    long result = 0;
    // Due to the way we shift, we can stop iterating once we've run out of data, the rest
    // of the result already being filled with zeros.

    // This loop is critical to performance, so please check HashBenchmark if altering it.
    int limit = Math.min(length, 8);
    for (int i = 0; i < limit; i++) {

};

TEST_P(CppGradients, TestIdentityNGrad) {
  // This test is interesting because the current implementation of GradientTape
  // would return [0, 1] whereas we use build_default_zeros_grads=false here
  // so we get back [nullptr, 1].

  AbstractTensorHandlePtr x1;
  {
    AbstractTensorHandle* x1_raw = nullptr;
    status_ = TestScalarTensorHandle<float, TF_FLOAT>(

    assertThat(Adapters.INTEGER_AS_LONG.fromDer(bytes)).isEqualTo(-549755813887L)
    assertThat(Adapters.INTEGER_AS_LONG.toDer(-549755813887L)).isEqualTo(bytes)
  }

  @Test fun `eight zeros`() {
    val bytes = "020200ff".decodeHex()
    assertThat(Adapters.INTEGER_AS_LONG.fromDer(bytes)).isEqualTo(255)
    assertThat(Adapters.INTEGER_AS_LONG.toDer(255)).isEqualTo(bytes)
  }

			c = ' ' // Treat the checksum field itself as all spaces.
		}
		unsigned += int64(c)
		signed += int64(int8(c))
	}
	return unsigned, signed
}

// reset clears the block with all zeros.
func (b *block) reset() {
	*b = block{}
}

type headerV7 [blockSize]byte

func (h *headerV7) name() []byte     { return h[000:][:100] }
func (h *headerV7) mode() []byte     { return h[100:][:8] }