# DP: Revert the fix for PC c++/88419, causing PR c++/89906.

2019-03-08  Jason Merrill  <jason@redhat.com>

	PR c++/88419 - C++17 ICE with class template arg deduction.
	* pt.c (make_template_placeholder): Set TYPE_CANONICAL after
	CLASS_PLACEHOLDER_TEMPLATE.

--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -26002,10 +26002,8 @@
 tree
 make_template_placeholder (tree tmpl)
 {
-  tree t = make_auto_1 (DECL_NAME (tmpl), false);
+  tree t = make_auto_1 (DECL_NAME (tmpl), true);
   CLASS_PLACEHOLDER_TEMPLATE (t) = tmpl;
-  /* Our canonical type depends on the placeholder.  */
-  TYPE_CANONICAL (t) = canonical_type_parameter (t);
   return t;
 }
 
--- a/gcc/testsuite/g++.dg/cpp1z/class-deduction62.C
+++ b/gcc/testsuite/g++.dg/cpp1z/class-deduction62.C
@@ -1,22 +0,0 @@
-// PR c++/88419
-// { dg-do compile { target c++17 } }
-
-template<class> struct ref_view {
-  template<class T> ref_view(T&&);
-};
-
-template<class R> ref_view(R&) -> ref_view<R>;
-
-struct ref_fn {
-  template<class R> auto operator()(R r) const
-    noexcept(noexcept(ref_view{r}));
-};
-
-template<class R> struct indirect_view {
-  indirect_view(R);
-};
-
-struct indirect_fn {
-  template<class R> auto operator()(R r) const
-    noexcept(noexcept(indirect_view{r}));
-};