Index: plugins/rt_topo/laa3_solve.c
===================================================================
--- plugins/rt_topo/laa3_solve.c	(revision 1376)
+++ plugins/rt_topo/laa3_solve.c	(revision 1377)
@@ -358,7 +358,7 @@
 				tn->y1 = tn->br.array[0].y = via->y;
 			}
 			idx = tn->br.used-1;
-			assert(idx > 0);
+			assert(idx >= 0);
 			via = tn->br.array[idx].via;
 			if (via != NULL) {
 printf("via end adjust2: %f;%f -> %f;%f\n", tn->x2, tn->y2, via->x, via->y);