diff --git a/arch/x86/include/asm/mc146818rtc.h b/arch/x86/include/asm/mc146818rtc.h
index 01fdf5674e24..0e8e85bb7c51 100644
--- a/arch/x86/include/asm/mc146818rtc.h
+++ b/arch/x86/include/asm/mc146818rtc.h
@@ -81,8 +81,8 @@ static inline unsigned char current_lock_cmos_reg(void)
 #else
 #define lock_cmos_prefix(reg) do {} while (0)
 #define lock_cmos_suffix(reg) do {} while (0)
-#define lock_cmos(reg)
-#define unlock_cmos()
+#define lock_cmos(reg) do { } while (0)
+#define unlock_cmos() do { } while (0)
 #define do_i_have_lock_cmos() 0
 #define current_lock_cmos_reg() 0
 #endif