re PR sanitizer/79897 (ICE in gimplify_modify_expr, at gimplify.c:5627 on ARM target)

	PR sanitizer/79897
	* ubsan.c (ubsan_encode_value): Call mark_addressable on the
	temporary.

	* c-c++-common/ubsan/pr79897.c: New test.

From-SVN: r245945

gcc/ChangeLog

+2017-03-07  Jakub Jelinek  <jakub@redhat.com>
+
+	PR sanitizer/79897
+	* ubsan.c (ubsan_encode_value): Call mark_addressable on the
+	temporary.
+
 2017-03-06  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/79821

gcc/testsuite/ChangeLog

+2017-03-07  Jakub Jelinek  <jakub@redhat.com>
+
+	PR sanitizer/79897
+	* c-c++-common/ubsan/pr79897.c: New test.
+
 2017-03-06  Vladimir Makarov  <vmakarov@redhat.com>
 
 	PR rtl-optimization/79571

gcc/testsuite/c-c++-common/ubsan/pr79897.c

+/* PR sanitizer/79897 */
+/* { dg-do compile } */
+/* { dg-options "-fsanitize=enum -O2" } */
+
+enum E
+{
+  A = 0,
+  B = ~0U + 1LL
+} x = A;
+
+int
+main ()
+{
+  return x != A;
+}

gcc/ubsan.c

@@ -145,6 +145,7 @@ ubsan_encode_value (tree t, bool in_expand_p)
 	     code by making vars unnecessarily addressable.  */
 	  tree var = create_tmp_var (type);
 	  tree tem = build2 (MODIFY_EXPR, void_type_node, var, t);
+	  mark_addressable (var);
 	  if (in_expand_p)
 	    {
 	      rtx mem