diff --git a/testing/test_pdb.py b/testing/test_pdb.py
index a565cbd0d..8618473bb 100644
--- a/testing/test_pdb.py
+++ b/testing/test_pdb.py
@@ -402,5 +402,4 @@ class TestPDB(object):
         child = testdir.spawn_pytest("--pdbcls=custom_pdb:CustomPdb %s" % str(p1))
 
         child.expect('custom set_trace>')
-        if child.isalive():
-            child.wait()
+        self.flush(child)