--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/gcc.dg/pr84670-2.c	Thu Oct 25 07:37:49 2018 +0900
@@ -0,0 +1,33 @@
+/* { dg-do compile } */
+/* { dg-options "-Ofast" } */
+
+enum b
+{
+  c,
+  d
+};
+struct e
+{
+  enum b code;
+};
+struct f
+{
+  unsigned g;
+};
+int h, i;
+struct a
+{
+  struct e common;
+  struct f j;
+};
+
+struct a k (void)
+{
+  struct a *l;
+  do
+    if (l->common.code == d && l->j.g * 4)
+      ;
+    else
+      i = l->j.g | (l->common.code && l);
+  while (h && l->common.code == c);
+}