diff --git a/Makefile b/Makefile
index ea50f64..ca364c9 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,5 @@
 CC ?= gcc
-CFLAGS ?= -Wall -fPIC -Ihash -O2
+CFLAGS ?= -Wall -Wextra -fPIC -Ihash -O2
 AR ?= ar
 ARFLAGS ?= rcs