schema tree BUGFIX input buffer must be initialized
diff --git a/src/tree_schema.c b/src/tree_schema.c
index 5e74ebc..4a55eb6 100644
--- a/src/tree_schema.c
+++ b/src/tree_schema.c
@@ -562,6 +562,7 @@
     LY_CHECK_ARG_RET(NULL, node, NULL);
     if (buffer) {
         LY_CHECK_ARG_RET(node->module->ctx, buflen > 1, NULL);
+        buffer[0] = '\0';
     }
 
     switch (pathtype) {