diff --git a/firmware/Makefile.inc b/firmware/Makefile.inc
index 35e9ad6..db15fd6 100644
--- a/firmware/Makefile.inc
+++ b/firmware/Makefile.inc
@@ -3,7 +3,7 @@ CFLAGS += -save-temps
 CFLAGS += -std=gnu99 -Wall # implements C99, for <util/atomic.h>
 # this removes dead code and does global linker optimization
 #CFLAGS += -ffunction-sections -Wl,--gc-sections -Wl,--relax 
-CFLAGS += -Wall -Os  -I. -mmcu=atmega88 -lm -ffunction-sections -fdata-sections
+CFLAGS += -Wall -Os  -I. -mmcu=atmega88 -lm -ffunction-sections -fdata-sections -Wl,--relax -ffreestanding
 
 # further optimization:
 #CFLAGS += --param inline-call-cost=2