;   int Se = cinfo->Se;   int Al = cinfo->Al;   JBLOCKROW block;    entropy->next_output_byte = cinfo->dest->next_output_byte;   entropy->free_in_buffer = cinfo->dest->free_in_buffer;    /* Emit restart marker if needed */   if (cinfo->restart_interval)     if (entropy->restarts_to_go == 0)       emit_restart(entropy, entropy->next_restart_num);    /* Encode the MCU data block */   block = MCU_data[0];    /* Encode the AC coefficients per section G.0.0.0, fig. G.0 */      r = 0;   /* r = run length of zeros */       for (k = cinfo->Ss; k <= Se; k++) {     if ((temp = 