diff --git a/xpcom/reflect/xptcall/src/md/mac/xptcinvoke_mac.cpp b/xpcom/reflect/xptcall/src/md/mac/xptcinvoke_mac.cpp
index 04877ba5d9f7..9fab26dbe23a 100644
--- a/xpcom/reflect/xptcall/src/md/mac/xptcinvoke_mac.cpp
+++ b/xpcom/reflect/xptcall/src/md/mac/xptcinvoke_mac.cpp
@@ -1,4 +1,4 @@
-/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
  *
  * The contents of this file are subject to the Netscape Public License
  * Version 1.0 (the "NPL"); you may not use this file except in
diff --git a/xpcom/reflect/xptcall/src/md/mac/xptcstubs_mac.cpp b/xpcom/reflect/xptcall/src/md/mac/xptcstubs_mac.cpp
index 8917e49233bd..6f740b51660d 100644
--- a/xpcom/reflect/xptcall/src/md/mac/xptcstubs_mac.cpp
+++ b/xpcom/reflect/xptcall/src/md/mac/xptcstubs_mac.cpp
@@ -1,4 +1,4 @@
-/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+/* -*- Mode: C; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
  *
  * The contents of this file are subject to the Netscape Public License
  * Version 1.0 (the "NPL"); you may not use this file except in