diff --git a/utils_maintenance/clang_format_paths.py b/utils_maintenance/clang_format_paths.py
index 967eecd069fce1de7b74c636b3da526c577734b5..1ceabb7743f25f35aedd56fa11cbdade013df7ef 100755
--- a/utils_maintenance/clang_format_paths.py
+++ b/utils_maintenance/clang_format_paths.py
@@ -162,7 +162,7 @@ def main():
 
     args = argparse_create().parse_args()
 
-    use_default_paths = bool(args.paths)
+    use_default_paths = not bool(args.paths)
 
     paths = compute_paths(args.paths)
     print("Operating on:")
@@ -177,7 +177,7 @@ def main():
 
     # Always operate on all cmake files (when expanding tabs and no paths given).
     files_retab = [
-        f for f in source_files_from_git("." if use_default_paths else paths)
+        f for f in source_files_from_git((".",) if use_default_paths else paths)
         if f.endswith(extensions_only_retab)
         if f not in ignore_files
     ]