add a standard "all" target
diff --git a/lib/Makefile b/lib/Makefile
index 11ca471..8e2c976 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -14,6 +14,8 @@
 SRCS=$(wildcard *.c)
 OBJS=$(patsubst %.c,%.o,$(SRCS))
 
+all: $(TARGET)
+
 $(TARGET): $(OBJS)
 	$(AR) -cr $@ $^