re PR c++/90969 (ICE: tree check: expected array_type, have vector_type in…

re PR c++/90969 (ICE: tree check: expected array_type, have vector_type in array_ref_low_bound, at tree.c:13570)

	PR c++/90969
	* constexpr.c (cxx_eval_array_reference): Don't look through VCE from
	vector type if lval.

	* g++.dg/ext/vector38.C: New test.

From-SVN: r272654

gcc/cp/ChangeLog

+2019-06-25  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/90969
+	* constexpr.c (cxx_eval_array_reference): Don't look through VCE from
+	vector type if lval.
+
 2019-06-24  Jan Hubicka  <jh@suse.cz>
 
 	* lex.c (cxx_make_type): Set TYPE_CXX_ODR_P.

gcc/cp/constexpr.c

@@ -2616,7 +2616,8 @@ cxx_eval_array_reference (const constexpr_ctx *ctx, tree t,
 					   non_constant_p, overflow_p);
   if (*non_constant_p)
     return t;
-  if (TREE_CODE (ary) == VIEW_CONVERT_EXPR
+  if (!lval
+      && TREE_CODE (ary) == VIEW_CONVERT_EXPR
       && VECTOR_TYPE_P (TREE_TYPE (TREE_OPERAND (ary, 0)))
       && TREE_TYPE (t) == TREE_TYPE (TREE_TYPE (TREE_OPERAND (ary, 0))))
     ary = TREE_OPERAND (ary, 0);

gcc/testsuite/ChangeLog

+2019-06-25  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/90969
+	* g++.dg/ext/vector38.C: New test.
+
 2019-06-25  Martin Jambor  <mjambor@suse.cz>
 
 	PR ipa/90939

gcc/testsuite/g++.dg/ext/vector38.C

+// PR c++/90969
+// { dg-do compile }
+
+__attribute__ ((__vector_size__ (4))) int v;
+int &a = v[0];