diff --git a/mesonbuild/build.py b/mesonbuild/build.py
index c10bbffc2db0..3cedb78b807d 100644
--- a/mesonbuild/build.py
+++ b/mesonbuild/build.py
@@ -327,6 +327,8 @@ def copy_for_build_machine(self) -> Build:
         new.install_scripts = []
         new.postconf_scripts = []
         new.install_dirs = []
+        new.test_setups = {}
+        new.test_setup_default_name = None
         # TODO: what about dist scripts?
 
         return new