ATTiny watchdog setting

watchdog.c

uint8_t watchdog_count = 0;

ISR(WDT_vect) {
  // This vector is for the watchdog timer
  PORTA = PORTA | (1 << LED ); // The LED never goes on
  ++watchdog_count;
}

ISR(PCINT0_vect)
{
  //This vector is only here to wake unit up from sleep mode
}

int main() {
  while (1) {
    PORTA = PORTA & ~(1<<LED );
    ACSR = (1<<ACD); //Turn off Analog Comparator
    PRR = 0x0F; //Reduce all power right before sleep
    asm volatile ("sleep");
  }
  return 0;
}

void setup_watchdog() {
  TCCR0B = (1<<CS01); // Set Prescaler to 8

  GIFR = (1<<PCIF0); //Enable the Pin Change interrupts to monitor button presses
  GIMSK = (1<<PCIE0); //Enable Pin Change Interrupt Request
  PCMSK0 = (1<< BUTTON); 
  MCUCR = (1<<SM1)|(1<<SE); //Setup Power-down mode and enable sleep

  MCUSR &= ~(1<<WDRF); // clear the watchdog reset
  // set up watchdog timer  
  WDTCSR |= (1 << WDCE ) | ( 1 << WDE );
  WDTCSR |= (1 << WDIE ); 
  WDTCSR |= (1 << WDP3) | (1 << WDP0); // timer goes off every 8 seconds

  sei(); //Enable interrupts
}

Thanks!