Array decomposition fix.

	* decl.c (check_initializer): Always use build_aggr_init for array
	decomposition.

From-SVN: r244639

gcc/cp/ChangeLog

 2017-01-19  Jason Merrill  <jason@redhat.com>
 
+	* decl.c (check_initializer): Always use build_aggr_init for array
+	decomposition.
+
 	PR c++/79130 - decomposition and direct-initialization
 	* init.c (build_aggr_init): Communicate direct-initialization to
 	build_vec_init.

gcc/cp/decl.c

@@ -6299,14 +6299,14 @@ check_initializer (tree decl, tree init, int flags, vec<tree, va_gc> **cleanups)
       if (type == error_mark_node)
 	return NULL_TREE;
 
-      if ((type_build_ctor_call (type) || CLASS_TYPE_P (type)
-	   || (DECL_DECOMPOSITION_P (decl) && TREE_CODE (type) == ARRAY_TYPE))
-	  && !(flags & LOOKUP_ALREADY_DIGESTED)
-	  && !(init && BRACE_ENCLOSED_INITIALIZER_P (init)
-	       && CP_AGGREGATE_TYPE_P (type)
-	       && (CLASS_TYPE_P (type)
-		   || !TYPE_NEEDS_CONSTRUCTING (type)
-		   || type_has_extended_temps (type))))
+      if (((type_build_ctor_call (type) || CLASS_TYPE_P (type))
+	   && !(flags & LOOKUP_ALREADY_DIGESTED)
+	   && !(init && BRACE_ENCLOSED_INITIALIZER_P (init)
+		&& CP_AGGREGATE_TYPE_P (type)
+		&& (CLASS_TYPE_P (type)
+		    || !TYPE_NEEDS_CONSTRUCTING (type)
+		    || type_has_extended_temps (type))))
+	  || (DECL_DECOMPOSITION_P (decl) && TREE_CODE (type) == ARRAY_TYPE))
 	{
 	  init_code = build_aggr_init_full_exprs (decl, init, flags);
 

gcc/testsuite/g++.dg/cpp1z/decomp21.C

+// { dg-options -std=c++1z }
+
+int a[3];
+struct S { int b, c, d; } s;
+void
+foo ()
+{
+  auto [ b, c, d ] = a;
+  auto [ e, f, g ] = s;
+  auto [ h, i, j ] { s };
+  auto [ k, l, m ] { s, };
+  auto [ n, o, p ] { a };
+  auto [ q, r, t ] ( s );
+  auto [ u, v, w ] ( s, );      // { dg-error "expected primary-expression before '.' token" }
+  auto [ x, y, z ] ( a );       // { dg-error "expression list treated as compound expression in initializer" "" { target *-*-* } .-1 }
+}