--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/gcc.dg/loop-unswitch-5.c	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,51 @@
+/* PR middle-end/71691 */
+/* { dg-do run } */
+/* { dg-options "-fno-tree-vrp -O2 -funswitch-loops -fdump-tree-unswitch-details" } */
+
+/* Note: The -fno-tree-vrp above is only there to avoid VRP papering
+   over the problem.  */
+
+char b;
+short f;
+unsigned e;
+int g = 20;
+
+void
+foo ()
+{
+  int l, h;
+  for (l = 0; l <= 7; l++)
+    {
+      int j = 38;
+      if (g)
+	h = 0;
+      for (; h <= 7; h++)
+	{
+	  int i, k = b % (j % 4);
+	  g = f;
+	  for (;;)
+	    {
+	      j = 6 || b;
+	      if (e)
+		{
+		  for (; j; --j)
+		    if (k)
+		      __builtin_printf ("%d", 9);
+		  if (i)
+		    __builtin_printf ("%d", j);
+		}
+	      if (l)
+		continue;
+	      break;
+	    }
+	  i = f || b;
+	}
+    }
+}
+
+int
+main ()
+{
+  foo ();
+  return 0;
+}