diff --git a/check-style.py b/check-style.py
index 00aa2695a..091f59bcb 100755
--- a/check-style.py
+++ b/check-style.py
@@ -20,8 +20,8 @@ def run_diff(sha):
     return proc.stdout.strip().splitlines()
 
 def find_chunks(diff):
-    file_entry_re = re.compile('^\+\+\+ b/(.*)$')
-    diff_chunk_re = re.compile('^@@ -\d+,\d+ \+(\d+),(\d+)')
+    file_entry_re = re.compile(r'^\+\+\+ b/(.*)$')
+    diff_chunk_re = re.compile(r'^@@ -\d+,\d+ \+(\d+),(\d+)')
     file = None
     chunks = []