diff --git a/scripts/code_style.py b/scripts/code_style.py
index b12198d..07952b6 100755
--- a/scripts/code_style.py
+++ b/scripts/code_style.py
@@ -52,7 +52,7 @@
     return frozenset(word for s in checks for word in s.split())
 
 # Check for comment string indicating an auto-generated file
-AUTOGEN_RE = re.compile(r"Warning[ :-]+This file is (now )?auto[ -]generated",
+AUTOGEN_RE = re.compile(r"Warning[ :-]+This file is (now )?auto[ -]?generated",
                         re.ASCII | re.IGNORECASE)
 def is_file_autogenerated(filename):
     content = open(filename, encoding="utf-8").read()