+2017-02-22 Jason Merrill <jason@redhat.com>
+
+ * pt.c (do_class_deduction): Handle 0 argument case.
+
2017-02-22 Jakub Jelinek <jakub@redhat.com>
PR c++/79664
if (cands == NULL_TREE)
{
+ if (args->length() == 0)
+ {
+ /* Try tmpl<>. */
+ tree t = lookup_template_class (tmpl, NULL_TREE, NULL_TREE,
+ NULL_TREE, false, tf_none);
+ if (t != error_mark_node)
+ return t;
+ }
error ("cannot deduce template arguments for %qT, as it has "
"no deduction guides or user-declared constructors", type);
return error_mark_node;