-CFLAGS=-I../include -I../include/raw \
- -I../lwip/src/include -I../lwip/src/include/ipv4 \
- -nostdlib -nostdinc -fno-builtin -D__RAW__ \
- -Wall -Werror -std=gnu99 -Wstrict-aliasing=2 \
- -O1 -fno-merge-constants -fno-strict-aliasing
+CFLAGS+=-I../include -I../include/raw \
+ -I../lwip/src/include -I../lwip/src/include/ipv4 \
+ -nostdlib -nostdinc -fno-builtin -D__RAW__ \
+ -Wall -Werror -std=gnu99 -Wstrict-aliasing=2 \
+ -O1 -fno-merge-constants -fno-strict-aliasing