#else
-#define read_lock() 0
-#define read_unlock() 0
-#define cache_lock() 0
-#define cache_unlock() 0
-#define progress_lock() 0
-#define progress_unlock() 0
+#define read_lock() (void)0
+#define read_unlock() (void)0
+#define cache_lock() (void)0
+#define cache_unlock() (void)0
+#define progress_lock() (void)0
+#define progress_unlock() (void)0
#endif