PR c++/82152 - ICE with class deduction and inherited ctor.

	* pt.c (do_class_deduction): Ignore inherited ctors.

From-SVN: r259133

gcc/cp/ChangeLog

 2018-04-05  Jason Merrill  <jason@redhat.com>
 
+	PR c++/82152 - ICE with class deduction and inherited ctor.
+	* pt.c (do_class_deduction): Ignore inherited ctors.
+
 	PR c++/84665 - ICE with array of empty class.
 	* decl2.c (cp_check_const_attributes): Use fold_non_dependent_expr.
 

gcc/cp/pt.c

@@ -26217,6 +26217,10 @@ do_class_deduction (tree ptype, tree tmpl, tree init, int flags,
   // FIXME cache artificial deduction guides
   for (ovl_iterator iter (CLASSTYPE_CONSTRUCTORS (type)); iter; ++iter)
     {
+      /* Skip inherited constructors.  */
+      if (iter.using_p ())
+	continue;
+
       tree guide = build_deduction_guide (*iter, outer_args, complain);
       if (guide == error_mark_node)
 	return error_mark_node;

gcc/testsuite/g++.dg/cpp1z/class-deduction54.C

+// PR c++/82152
+// { dg-additional-options -std=c++17 }
+
+struct Base {};
+
+template<typename T>
+struct Derived : public Base {
+  using Base::Base;
+};
+
+Derived() -> Derived< void >;
+
+int main() {
+  Derived x;
+}