diff --git a/script/run-clang-format.py b/script/run-clang-format.py
index 4d2e4b0641c0..33548391c23e 100644
--- a/script/run-clang-format.py
+++ b/script/run-clang-format.py
@@ -55,8 +55,7 @@ def list_files(files, recursive=False, extensions=None, exclude=None):
                         x for x in fpaths if not fnmatch.fnmatch(x, pattern)
                     ]
                 for fp in fpaths:
-                    ext = os.path.splitext(f)[1][1:]
-                    print(ext)
+                    ext = os.path.splitext(fp)[1][1:]
                     if ext in extensions:
                         out.append(fp)
         else: