re PR c++/84874 (internal compiler error: in reshape_init_class, at cp/decl.c:5800)

	PR c++/84874
	* decl.c (reshape_init_class): Don't assert d->cur->index == field
	if d->cur->index is a FIELD_DECL, instead set field to d->cur->index.

	* g++.dg/cpp2a/desig7.C: New test.

From-SVN: r258585

gcc/cp/ChangeLog

+2018-03-16  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/84874
+	* decl.c (reshape_init_class): Don't assert d->cur->index == field
+	if d->cur->index is a FIELD_DECL, instead set field to d->cur->index.
+
 2018-03-15  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/84222

gcc/cp/decl.c

@@ -5885,8 +5885,17 @@ reshape_init_class (tree type, reshape_iter *d, bool first_initializer_p,
 	    return error_mark_node;
 
 	  if (TREE_CODE (d->cur->index) == FIELD_DECL)
-	    /* We already reshaped this.  */
-	    gcc_assert (d->cur->index == field);
+	    {
+	      /* We already reshaped this.  */
+	      if (field != d->cur->index)
+		{
+		  tree id = DECL_NAME (d->cur->index);
+		  gcc_assert (id);
+		  gcc_checking_assert (d->cur->index
+				       == get_class_binding (type, id, false));
+		  field = d->cur->index;
+		}
+	    }
 	  else if (TREE_CODE (d->cur->index) == IDENTIFIER_NODE)
 	    field = get_class_binding (type, d->cur->index, false);
 	  else

gcc/testsuite/ChangeLog

+2018-03-16  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/84874
+	* g++.dg/cpp2a/desig7.C: New test.
+
 03-16-2018  Mark Doffman  <mark.doffman@codethink.co.uk>
             Jim MacArthur  <jim.macarthur@codethink.co.uk>
 

gcc/testsuite/g++.dg/cpp2a/desig7.C

+// PR c++/84874
+// { dg-do run { target c++11 } }
+// { dg-options "" }
+
+struct A { int a, b; };
+struct B { A d; };
+
+void
+foo (B *x)
+{
+  *x = { .d = { .b = 5 } };
+}
+
+void
+bar (A *x)
+{
+  *x = { .b = 6 };
+}
+
+int
+main ()
+{
+  B b = { { 2, 3 } };
+  foo (&b);
+  if (b.d.a != 0 || b.d.b != 5)
+    __builtin_abort ();
+  b.d.a = 8;
+  bar (&b.d);
+  if (b.d.a != 0 || b.d.b != 6)
+    __builtin_abort ();
+}