Index: gcc/sched-vis.c
===================================================================
--- gcc/sched-vis.c     (revision 192992)
+++ gcc/sched-vis.c     (working copy)
@@ -568,6 +568,11 @@ print_pattern (char *buf, const_rtx x, int verbose
 {
   char t1[BUF_LEN], t2[BUF_LEN], t3[BUF_LEN];

+  if (! x)
+    {
+      sprintf (buf, "(nil)");
+      return;
+    }
   switch (GET_CODE (x))
     {
     case SET: