diff --git a/rts/include/stg/SMP.h b/rts/include/stg/SMP.h
index 6cdbb15d14917fef5302277201481247b079cc45..a4483285431756c18630e423360ebbd62d7e9f64 100644
--- a/rts/include/stg/SMP.h
+++ b/rts/include/stg/SMP.h
@@ -589,9 +589,9 @@ load_load_barrier(void) {
 EXTERN_INLINE void write_barrier(void);
 EXTERN_INLINE void store_load_barrier(void);
 EXTERN_INLINE void load_load_barrier(void);
-EXTERN_INLINE void write_barrier     () {} /* nothing */
-EXTERN_INLINE void store_load_barrier() {} /* nothing */
-EXTERN_INLINE void load_load_barrier () {} /* nothing */
+EXTERN_INLINE void write_barrier     (void) {} /* nothing */
+EXTERN_INLINE void store_load_barrier(void) {} /* nothing */
+EXTERN_INLINE void load_load_barrier (void) {} /* nothing */
 
 // Relaxed atomic operations
 #define RELAXED_LOAD(ptr) *ptr