Index: main/pbx.c
===================================================================
--- main/pbx.c	(revision 194141)
+++ main/pbx.c	(working copy)
@@ -6775,11 +6775,10 @@
 		/* Fill the mask. Remember that ranges are cyclic */
 		mask |= (1 << end);   /* initialize with last element */
 		while (start != end) {
-			if (start >= max) {
+			mask |= (1 << start);
+			if (++start >= max) {
 				start = 0;
 			}
-			mask |= (1 << start);
-			start++;
 		}
 	}
 	return mask;