diff --git a/stack.h b/stack.h
index 9796be5f47ab539a622deaa3bf8b563157b7c7ab..4a13e3eb4298c34e104a227245df1a76a4a2fa4d 100644
--- a/stack.h
+++ b/stack.h
@@ -7,4 +7,6 @@ typedef struct _stack {
     int top;
 } stack;
 
+void stack_destroy(stack *s);
+
 #endif