diff --git a/bintree.c b/bintree.c
index ebd01f2..dff08d5 100644
--- a/bintree.c
+++ b/bintree.c
@@ -88,7 +88,7 @@ void *nextTreeData(TreeNode *root)
         return NULL;
 
     /* Top-Element vom Stack holen */
-    StackNode *sn = pop(&stack);
+    StackNode *sn = pop(stack);
     if (sn == NULL)
         return NULL;
 
diff --git a/makefile b/makefile
index 3c11204..f4056fa 100644
--- a/makefile
+++ b/makefile
@@ -41,18 +41,25 @@ stack_test_objects = $(stack_test_sources:.c=.o)
 numbers_test_sources = test_numbers.c numbers.c
 numbers_test_objects = $(numbers_test_sources:.c=.o)
 
+bintree_test_sources = test_bintree.c bintree.c
+bintree_test_objects = $(bintree_test_sources:.c=.o)
+
 stack_test_runner: $(stack_test_objects)
 	$(CC) $(FLAGS) $^ -o $@
 
 numbers_test_runner: $(numbers_test_objects)
 	$(CC) $(FLAGS) $^ -o $@
 
-unitTests: stack_test_runner numbers_test_runner
+bintree_test_runner: $(bintree_test_objects)
+	$(CC) $(FLAGS) $^ -o $@
+
+unitTests: stack_test_runner numbers_test_runner bintree_test_runner
 	@echo "============================="
 	@echo "Running Unit Tests..."
 	@echo "============================="
 	./stack_test_runner
 	./numbers_test_runner
+	./bintree_test_runner
 	@echo "============================="
 	@echo "Unit Tests Finished."
 	@echo "============================="