AVR: Interrupt build error

Question

I am trying to learn how to use interrupts for a project using an Attiny85. I have written a simple program from what I have learned from tutorials. However when I try to build the program in Atmel Studio, I get this error message:

"Error 2 static declaration of '__vector_1' follows non-static declaration"

I do not understand what this means or where my mistake located. I've searched all around for answers but I haven't found the reason for the error yet. Here is my code:

#include <avr/io.h>
#include <util/delay.h>
#include <avr/interrupt.h>
#include <avr/sleep.h>
int main (void)
{
 DDRB = 0b11111011; // set all pins to be output except PB2 to prevent false signals 
 GIMSK |= (1<<INT0); //set PB2 to interrupt
 sei();
 MCUCR |=(1<<ISC00); //set to detect any change as interrupt
 MCUCR &= ~(1<<ISC01);
 ISR(INT0_vect)
 {
 // dot
 PORTB = 0b00001000;
 _delay_ms(500);
 PORTB = 0b00000000;
 _delay_ms(200);
 // dot
 PORTB = 0b00001000;
 _delay_ms(500);
 PORTB = 0b00000000;
 _delay_ms(200);
 // dot
 PORTB = 0b00001000;
 _delay_ms(500);
 PORTB = 0b00000000;
 _delay_ms(600);
 // dash
 PORTB = 0b00001000;
 _delay_ms(1000);
 PORTB = 0b00000000;
 _delay_ms(500);
 // dash
 PORTB = 0b00001000;
 _delay_ms(1000);
 PORTB = 0b00000000;
 _delay_ms(500);
 // dash
 PORTB = 0b00001000;
 _delay_ms(1000);
 PORTB = 0b00000000;
 _delay_ms(600);
 // dot
 PORTB = 0b00001000;
 _delay_ms(500);
 PORTB = 0b00000000;
 _delay_ms(200);
 // dot
 PORTB = 0b00001000;
 _delay_ms(500);
 PORTB = 0b00000000;
 _delay_ms(200);
 // dot
 PORTB = 0b00001000;
 _delay_ms(500);
 PORTB = 0b00000000;
 _delay_ms(2000);
 }
 while (1) {
 }
 }

If anyone could provide assistance it would be much appreciated.

Thank you,

-David

Answer 1

You've written your ISR within main(). Don't do that; close the previous function first.

void main(void)
{
 ...
}
ISR(...)
{
 ...
}