Assembler in C - Error

// gcc -o asmtest.bin asmtest.c

#include <stdio.h>

int dodaj(int x, int y){
    __asm{
        /* Intel
        mov eax,[esp+4]
        add eax,[esp+8]
        retn
        */
        movl +4(%esp), %eax
        add +8(%esp), %eax
        ret
    }
}

int main(){
    int x,y;
    scanf("%d%d",&x,&y);
    printf(dodaj(x,y));
    return 0;
}