diff --git a/tools/db_crashtest.py b/tools/db_crashtest.py
index 063a3ce9f..1531806e5 100644
--- a/tools/db_crashtest.py
+++ b/tools/db_crashtest.py
@@ -206,12 +206,12 @@ def blackbox_crash_main(args, unknown_args):
 
         while True:
             line = child.stderr.readline().strip()
-            if line != '' and not line.startswith('WARNING'):
+            if line == '':
+                break
+            elif not line.startswith('WARNING'):
                 run_had_errors = True
                 print('stderr has error message:')
                 print('***' + line + '***')
-            else:
-                break
 
         if run_had_errors:
             sys.exit(2)