$ make
rm -f main.hex main.eep main.cof main.elf \
main.map main.sym main.lss \
main.o gameoflife.o graphicfunctions.o graphicint.o text.o    main.lst gameoflife.lst graphicfunctions.lst graphicint.lst text.lst main.s gameoflife.s graphicfunctions.s graphicint.s text.s main.d gameoflife.d graphicfunctions.d graphicint.d text.d
avr-gcc -c -mmcu=atmega32 -I. -gstabs   -O2 -ffast-math -fweb -frename-registers -Winline -mtiny-stack -Wall -Wstrict-prototypes -std=gnu99  main.c -o main.o
avr-gcc -c -mmcu=atmega32 -I. -gstabs   -O2 -ffast-math -fweb -frename-registers -Winline -mtiny-stack -Wall -Wstrict-prototypes -std=gnu99  gameoflife.c -o gameoflife.o
avr-gcc -c -mmcu=atmega32 -I. -gstabs   -O2 -ffast-math -fweb -frename-registers -Winline -mtiny-stack -Wall -Wstrict-prototypes -std=gnu99  graphicfunctions.c -o graphicfunctions.o
avr-gcc -c -mmcu=atmega32 -I. -gstabs   -O2 -ffast-math -fweb -frename-registers -Winline -mtiny-stack -Wall -Wstrict-prototypes -std=gnu99  graphicint.c -o graphicint.o
avr-gcc -c -mmcu=atmega32 -I. -gstabs   -O2 -ffast-math -fweb -frename-registers -Winline -mtiny-stack -Wall -Wstrict-prototypes -std=gnu99  text.c -o text.o
avr-gcc -mmcu=atmega32 -I. -gstabs   -O2 -ffast-math -fweb -frename-registers -Winline -mtiny-stack -Wall -Wstrict-prototypes -std=gnu99  main.o gameoflife.o graphicfunctions.o graphicint.o text.o   --output main.elf     -lm
gameoflife.o(.text+0x0): In function `pixel_get':
graphicfunctions.h:23: multiple definition of `pixel_get'
main.o(.text+0x0):graphicfunctions.h:23: first defined here
graphicfunctions.o(.text+0x0): In function `pixel_get':
graphicfunctions.h:23: multiple definition of `pixel_get'
main.o(.text+0x0):graphicfunctions.h:23: first defined here
graphicint.o(.text+0x0): In function `pixel_get':
graphicfunctions.h:23: multiple definition of `pixel_get'
main.o(.text+0x0):graphicfunctions.h:23: first defined here
text.o(.text+0x0): In function `pixel_get':
graphicfunctions.h:23: multiple definition of `pixel_get'
main.o(.text+0x0):graphicfunctions.h:23: first defined here
make: *** [main.elf] Fehler 1
$