diff --git a/tests/kphp_tester.py b/tests/kphp_tester.py
index abb6253249..ce2cb96f2c 100755
--- a/tests/kphp_tester.py
+++ b/tests/kphp_tester.py
@@ -60,7 +60,7 @@ def make_kphp_once_runner(self, use_nocc, cxx_name, k2_bin):
             vkext_dir=os.path.abspath(os.path.join(tester_dir, os.path.pardir, "objs", "vkext")),
             use_nocc=use_nocc,
             cxx_name=cxx_name,
-            k2_bin=os.path.abspath(k2_bin)
+            k2_bin=None if k2_bin is None else os.path.abspath(k2_bin)
         )
 
     def set_up_env_for_k2(self, cxx_name="clang++"):