Index: mucs.c
===================================================================
--- mucs.c	(revision 8318)
+++ mucs.c	(revision 8319)
@@ -59,7 +59,7 @@
 	pcb_coord_t x1, y1, x2, y2, r;
 	fname = argc ? argv[0] : 0;
 
-	if (!(pcb_layer_flags(INDEXOFCURRENT) & PCB_LYT_COPPER)) {
+	if (!(pcb_layer_flags(PCB, INDEXOFCURRENT) & PCB_LYT_COPPER)) {
 		pcb_message(PCB_MSG_ERROR, "The currently active layer is not a copper layer.\n");
 	}