h2 += h1;

      h1 = fmix64(h1);
      h2 = fmix64(h2);

      h1 += h2;
      h2 += h1;

      return HashCode.fromBytesNoCopy(
          ByteBuffer.wrap(new byte[CHUNK_SIZE])
              .order(ByteOrder.LITTLE_ENDIAN)
              .putLong(h1)
              .putLong(h2)
              .array());
    }

    private static long fmix64(long k) {
      k ^= k >>> 33;

			// See: https://golang.org/issue/6506.
			"-fno-builtin",
		)
	}

	c = append(c, p.GccOptions...)
	c = append(c, gccMachine()...)
	if goos == "aix" {
		c = append(c, "-maix64")
		c = append(c, "-mcmodel=large")
	}
	// disable LTO so we get an object whose symbols we can read
	c = append(c, "-fno-lto")
	c = append(c, "-") //read input from standard input
	return c
}