diff --git a/src/list.c b/src/list.c
index 001f8ed..7eaa6c6 100644
--- a/src/list.c
+++ b/src/list.c
@@ -76,7 +76,7 @@ bool list_pop(struct _list* self, int index, void* obj)
 	return true;
 }
 
-uint32_t list_index(struct _list* self, void* obj)
+int list_index(struct _list* self, void* obj)
 {
 	return 0;
 }
diff --git a/test/test.h b/test/test.h
index 902ae04..30575df 100644
--- a/test/test.h
+++ b/test/test.h
@@ -19,9 +19,11 @@
 	#endif
 #endif
 
-void stack_test(void);
-void queue_test(void);
 void list_test(void);
+void stack_test(void);
+void deque_test(void);
+
+void queue_test(void);
 void tree_test(void);
 void rbtree_test(void);