set depedency for .h files

# means that include file dependencies are broken, so sometimes when

# the program crashes unexpectedly, 'make clean' then 'make' fixes the

# problem that a .h file was out of date

tmp/%.o: src/%.c

tmp/%.o: src/%.c src/*.h

	$(CC) $(CFLAGS) -c $< -o $@

SRC = $(wildcard src/*.c)