Codevision Compiler Errorz(AVR/io.h)

#include <C:\cvavr2\inc\io.h>
#include <stdlib.h>
#define F_CPU 16000000UL
#include <util/delay.h>
#define BAUDRATE 9600
#define BAUD_PRESCALLER (((F_CPU / (BAUDRATE * 16UL))) - 1)
 
uint16_t adc_value;            //Variable used to store the value read from the ADC
char buffer[5];                //Output of the itoa function
uint8_t i=0;                //Variable for the for() loop
 
void adc_init(void);            //Function to initialize/configure the ADC
uint16_t read_adc(uint8_t channel);    //Function to read an arbitrary analogic channel/pin
void USART_init(void);            //Function to initialize and configure the USART/serial
void USART_send( unsigned char data);    //Function that sends a char over the serial port
void USART_putstring(char* StringPtr);    //Function that sends a string over the serial port
 
int main(void){
adc_init();        //Setup the ADC
USART_init();        //Setup the USART
 
for(;;){        //Our infinite loop
 for(i=0; i<6; i++){
 USART_putstring("Reading channel ");
 USART_send('0' + i);            //This is a nifty trick when we only want to send a number between 0 and 9
 USART_putstring(" : ");            //Just to keep things pretty
 adc_value = read_adc(i);        //Read one ADC channel
 itoa(adc_value, buffer, 10);        //Convert the read value to an ascii string
 USART_putstring(buffer);        //Send the converted value to the terminal
 USART_putstring("  ");            //Some more formatting
 _delay_ms(500);                //You can tweak this value to have slower or faster readings or for max speed remove this line
 }
 USART_send('\r');
 USART_send('\n');                //This two lines are to tell to the terminal to change line
}
 
return 0;
}
 
void adc_init(void){
 ADCSRA |= ((1<<ADPS2)|(1<<ADPS1)|(1<<ADPS0));    //16Mhz/128 = 125Khz the ADC reference clock
 ADMUX |= (1<<REFS0);                //Voltage reference from Avcc (5v)
 ADCSRA |= (1<<ADEN);                //Turn on ADC
 ADCSRA |= (1<<ADSC);                //Do an initial conversion because this one is the slowest and to ensure that everything is up and running
}
 
uint16_t read_adc(uint8_t channel){
 ADMUX &= 0xF0;                    //Clear the older channel that was read
 ADMUX |= channel;                //Defines the new ADC channel to be read
 ADCSRA |= (1<<ADSC);                //Starts a new conversion
 while(ADCSRA & (1<<ADSC));            //Wait until the conversion is done
 return ADCW;                    //Returns the ADC value of the chosen channel
}
 
void USART_init(void){
 
 UBRR0H = (uint8_t)(BAUD_PRESCALLER>>8);
 UBRR0L = (uint8_t)(BAUD_PRESCALLER);
 UCSR0B = (1<<RXEN0)|(1<<TXEN0);
 UCSR0C = (3<<UCSZ00);
}
 
void USART_send( unsigned char data){
 
 while(!(UCSR0A & (1<<UDRE0)));
 UDR0 = data;
 
}
 
void USART_putstring(char* StringPtr){
 
while(*StringPtr != 0x00){
 USART_send(*StringPtr);
 StringPtr++;}
 
}
}

#include <avr/io.h>
#include <util/delay.h>
#include <avr/interrupt.h>
#include <avr/pgmspace.h>
#include <avr/cvavr_compat.h>


int main(void)
{
    while(1)
    {
     
    }
}

#include <mega328p.h>

// Declare your global variables here

void main(void)
{
// Declare your local variables here

// Crystal Oscillator division factor: 1
#pragma optsize-
CLKPR=0x80;
CLKPR=0x00;
#ifdef _OPTIMIZE_SIZE_
#pragma optsize+
#endif

while (1)
      {
      // Place your code here

      };
}

#include <avr/io.h>

#include <avr/io.h>
#include <stdlib.h>
#define F_CPU 16000000UL
#include <util/delay.h>
#define BAUDRATE 9600
#define BAUD_PRESCALLER (((F_CPU / (BAUDRATE * 16UL))) - 1)

uint16_t adc_value;            //Variable used to store the value read from the ADC
char buffer[5];                //Output of the itoa function
uint8_t i=0;                //Variable for the for() loop

void adc_init(void);            //Function to initialize/configure the ADC
uint16_t read_adc(uint8_t channel);    //Function to read an arbitrary analogic channel/pin
void USART_init(void);            //Function to initialize and configure the USART/serial
void USART_send( unsigned char data);    //Function that sends a char over the serial port
void USART_putstring(char* StringPtr);    //Function that sends a string over the serial port

int main(void) {
    adc_init();        //Setup the ADC
    USART_init();        //Setup the USART

    for(;;) {       //Our infinite loop
        for(i=0; i<6; i++) {
            USART_putstring("Reading channel ");
            USART_send('0' + i);            //This is a nifty trick when we only want to send a number between 0 and 9
            USART_putstring(" : ");            //Just to keep things pretty
            adc_value = read_adc(i);        //Read one ADC channel
            itoa(adc_value, buffer, 10);        //Convert the read value to an ascii string
            USART_putstring(buffer);        //Send the converted value to the terminal
            USART_putstring("  ");            //Some more formatting
            _delay_ms(500);                //You can tweak this value to have slower or faster readings or for max speed remove this line
        }
        USART_send('\r');
        USART_send('\n');                //This two lines are to tell to the terminal to change line
    }

    return 0;
}

void adc_init(void) {
    ADCSRA |= ((1<<ADPS2)|(1<<ADPS1)|(1<<ADPS0));    //16Mhz/128 = 125Khz the ADC reference clock
    ADMUX |= (1<<REFS0);                //Voltage reference from Avcc (5v)
    ADCSRA |= (1<<ADEN);                //Turn on ADC
    ADCSRA |= (1<<ADSC);                //Do an initial conversion because this one is the slowest and to ensure that everything is up and running
}

uint16_t read_adc(uint8_t channel) {
    ADMUX &= 0xF0;                    //Clear the older channel that was read
    ADMUX |= channel;                //Defines the new ADC channel to be read
    ADCSRA |= (1<<ADSC);                //Starts a new conversion
    while(ADCSRA & (1<<ADSC));            //Wait until the conversion is done
    return ADCW;                    //Returns the ADC value of the chosen channel
}

void USART_init(void) {

    UBRR0H = (uint8_t)(BAUD_PRESCALLER>>8);
    UBRR0L = (uint8_t)(BAUD_PRESCALLER);
    UCSR0B = (1<<RXEN0)|(1<<TXEN0);
    UCSR0C = (3<<UCSZ00);
}

void USART_send( unsigned char data) {

    while(!(UCSR0A & (1<<UDRE0)));
    UDR0 = data;

}

void USART_putstring(char* StringPtr) {

    while(*StringPtr != 0x00) {
        USART_send(*StringPtr);
        StringPtr++;
    }

}