-#define diff_debug_filespec(a,b,c) do {} while(0)
-#define diff_debug_filepair(a,b) do {} while(0)
-#define diff_debug_queue(a,b) do {} while(0)
+#define diff_debug_filespec(a,b,c) do { /* nothing */ } while (0)
+#define diff_debug_filepair(a,b) do { /* nothing */ } while (0)
+#define diff_debug_queue(a,b) do { /* nothing */ } while (0)