diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 4878aa2b2e4..57bf533207d 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,7 @@
+Fri Oct  9 11:44:47 1998  David Edelsohn  <edelsohn@mhpcc.edu>
+
+	* loop.c (insert_bct): Ensure loop_iteration_var non-zero before use.
+
 Thu Oct  8 21:59:47 1998  Dave Brolley  <brolley@cygnus.com>
 
 	* emit-rtl.c (init_emit_once): Call INIT_EXPANDERS.
diff --git a/gcc/loop.c b/gcc/loop.c
index dc4eaa9466d..556877feff9 100644
--- a/gcc/loop.c
+++ b/gcc/loop.c
@@ -8054,12 +8054,21 @@ insert_bct (loop_start, loop_end)
      at compile time.  In this case we generate run_time calculation
      of the number of iterations.  */
 
+  if (loop_iteration_var == 0)
+    {
+      if (loop_dump_stream)
+	fprintf (loop_dump_stream,
+		 "insert_bct %d: BCT Runtime Instrumentation failed: no loop iteration variable found\n",
+		 loop_num);
+      return;
+    }
+
   if (GET_MODE_CLASS (GET_MODE (loop_iteration_var)) != MODE_INT
       || GET_MODE_SIZE (GET_MODE (loop_iteration_var)) != UNITS_PER_WORD)
     {
       if (loop_dump_stream)
 	fprintf (loop_dump_stream,
-		 "insert_bct %d: BCT Instrumentation failed: loop variable not integer\n",
+		 "insert_bct %d: BCT Runtime Instrumentation failed: loop variable not integer\n",
 		 loop_num);
       return;
     }
@@ -8069,7 +8078,7 @@ insert_bct (loop_start, loop_end)
     {
       if (loop_dump_stream)
 	fprintf (loop_dump_stream,
-		 "insert_bct %d: runtime bounds with != comparison\n",
+		 "insert_bct %d: BCT Runtime Instrumentation failed: runtime bounds with != comparison\n",
 		 loop_num);
       return;
     }