recipe for target 'main.o' failed.

#define F_CPU 16000000UL

#include <avr/io.h>

#define F_CPU 16000000UL

#include "avr/delay.h"

#include "avr/interrupt.h"

#include "main.h"

#include "i2clcd.h"

#include "i2cmaster.h"

#define LED4       (1<<DDRB4)

#define LED3       (1<<DDRB5)

#define LED4on     PORTB |= (1<<LED4)

#define LED4off    PORTB &= ~ (1<<LED4)

#define LED3on     PORTB |= (1<<LED4)

#define LED3off    PORTB &= ~ (1<<LED4)

#define SW2        DDRD &= ~(1<<DDRD3)

volatile int var;

ISR (INT1_vect)

{

  PORTB ^= (1<<LED4);

  var++;

}

int myfunc(void){

  DDRB = 0xFF;

  while(1)

  {

    LED4on;

    _delay_ms(200);

    LED4off;

    _delay_ms(800);

  }

  DDRB = 0xFF;

  while(1)

  {

    LED4on;

    LED3off;

    _delay_ms(100);

    LED4off;

    LED3on;

    _delay_ms(400);

  }

  char oldStatusPinD = 1;

  char newStatusPinD = 1;

  DDRD &= ~(1<<PIND3);

  DDRB |= (1<<PORTB3);

  while (1){

    newStatusPinD = (PIND & (1 << PIND3));

    if((!newStatusPinD)  && (oldStatusPinD)){

      PORTB ^=(1<<PORTB4);

    }   oldStatusPinD = newStatusPinD;          }

    DDRB |= (1<<DDRB4);

    DDRD &= ~(1<<DDRD3);

    sei();

    EIMSK |= (1<<INT1);

    EICRA |= (1<<ISC01);

    while(1){

    }

    sei();

    EIMSK |= (1<<INT1);

    EICRA |= (1<<ISC01);

    var = 0;

    i2c_init();

    lcd_init();

    lcd_light(true);

    char zeile[17] = {};

    while(1)

    {

      sprintf(zeile, "%i" ,var);

      lcd_printlc(1, 1, zeile);

      }*/