diff --git a/Makefile b/Makefile
index cfb8c56..aaa7d2e 100644
--- a/Makefile
+++ b/Makefile
@@ -12,7 +12,7 @@ all: $(TARGET)
 
 $(TARGET): $(SRC)
 	mkdir -p build
-	avr-gcc -o $@.elf $^ $(CPPFLAGS) $(CFLAGS) $(INC)
+	avr-gcc -o $@.elf $^ $(CPPFLAGS) $(CFLAGS) $(INC) -Wl,-u,vfprintf -lprintf_flt -lm
 	avr-objcopy -j .text -j .data -O ihex $@.elf $@.hex
 	rm $@.elf