diff --git a/bintree.c b/bintree.c
index 1da97a8..97b4e7b 100644
--- a/bintree.c
+++ b/bintree.c
@@ -80,7 +80,7 @@ void *nextTreeData(TreeNode *root)
 
         if (stack)
         {
-            clearStack(&stack);
+            clearStack(stack);
             stack = NULL;
         }
         //leeren Stack initialisieren