diff --git a/Lib/test/ssltests.py b/Lib/test/ssltests.py
index 292453a813d..5073ae12204 100644
--- a/Lib/test/ssltests.py
+++ b/Lib/test/ssltests.py
@@ -16,7 +16,7 @@ def run_regrtests(*extra_args):
     print(ssl.OPENSSL_VERSION)
     args = [
         sys.executable,
-        # '-Werror', '-bb',  # turn warnings into exceptions
+        '-Werror', '-bb',  # turn warnings into exceptions
         '-m', 'test',
     ]
     if not extra_args: