diff --git a/Lib/test/test_math.py b/Lib/test/test_math.py
index 1f31dc5794f..1452035bc5e 100644
--- a/Lib/test/test_math.py
+++ b/Lib/test/test_math.py
@@ -181,3 +181,5 @@ try:
     x = math.sqrt(-1.0)
 except ValueError:
     pass
+else:
+    raise TestFailed("sqrt(-1) didn't raise ValueError")