trees BUGFIX checking failure of the called functions
diff --git a/src/tree_schema.c b/src/tree_schema.c
index 0b88687..b958df4 100644
--- a/src/tree_schema.c
+++ b/src/tree_schema.c
@@ -772,6 +772,7 @@
         break;
     default:
         LOGERR(ctx, LY_EINVAL, "Invalid schema input format.");
+        ret = LY_EINVAL;
         break;
     }
     LY_CHECK_GOTO(ret, error);