PR c++/89966 - error with non-type auto tparm.

My patch for PR 86932 broke this testcase by passing tf_partial to
coerce_template_template_parms, which prevented do_auto_deduction from
actually replacing the auto.

	* pt.c (do_auto_deduction): Clear tf_partial.

From-SVN: r270160

gcc/cp/ChangeLog

@@ -1,3 +1,8 @@
+2019-04-04  Jason Merrill  <jason@redhat.com>
+
+	PR c++/89966 - error with non-type auto tparm.
+	* pt.c (do_auto_deduction): Clear tf_partial.
+
 2019-04-04  Jason Merrill  <jason@redhat.com>
 
 	PR c++/86986 - ICE with TTP with parameter pack.

gcc/cp/pt.c

@@ -27504,6 +27504,10 @@ do_auto_deduction (tree type, tree init, tree auto_node,
   if (init && undeduced_auto_decl (init))
     return type;
 
+  /* We may be doing a partial substitution, but we still want to replace
+     auto_node.  */
+  complain &= ~tf_partial;
+
   if (tree tmpl = CLASS_PLACEHOLDER_TEMPLATE (auto_node))
     /* C++17 class template argument deduction.  */
     return do_class_deduction (type, tmpl, init, flags, complain);

gcc/testsuite/g++.dg/cpp1z/nontype-auto15.C

@@ -0,0 +1,6 @@
+// PR c++/89966
+// { dg-do compile { target c++17 } }
+
+template < auto a0 >
+void f0() { }
+void f0_call() { f0< sizeof(int) >(); }