re PR c++/92965 ("note: 'x' is not public" emitted even when no error is emitted)

	PR c++/92965
	* pt.c (invalid_nontype_parm_type_p): Call structural_type_p with
	explain=true only if emitting error.

	* g++.dg/cpp2a/nontype-class27.C: New test.

From-SVN: r279684

gcc/cp/ChangeLog

 2019-12-20  Jakub Jelinek  <jakub@redhat.com>
 
+	PR c++/92965
+	* pt.c (invalid_nontype_parm_type_p): Call structural_type_p with
+	explain=true only if emitting error.
+
 	PR c++/92966
 	* method.c (early_check_defaulted_comparison): Don't set
 	DECL_MAYBE_DELETED when returning false.

gcc/cp/pt.c

@@ -25838,11 +25838,13 @@ invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
 	return true;
       if (!structural_type_p (type))
 	{
-	  auto_diagnostic_group d;
 	  if (complain & tf_error)
-	    error ("%qT is not a valid type for a template non-type parameter "
-		   "because it is not structural", type);
+	    {
+	      auto_diagnostic_group d;
+	      error ("%qT is not a valid type for a template non-type "
+		     "parameter because it is not structural", type);
 	      structural_type_p (type, true);
+	    }
 	  return true;
 	}
       return false;

gcc/testsuite/ChangeLog

 2019-12-20  Jakub Jelinek  <jakub@redhat.com>
 
+	PR c++/92965
+	* g++.dg/cpp2a/nontype-class27.C: New test.
+
 	PR c++/92966
 	* g++.dg/cpp2a/spaceship-eq8.C: New test.
 

gcc/testsuite/g++.dg/cpp2a/nontype-class27.C

+// PR c++/92965
+// { dg-do compile { target c++2a } }
+
+template<int>
+class TS {
+  int x;	// { dg-bogus "is not public" }
+public:
+  constexpr TS(int) {}
+};
+TS(int) -> TS<1>;
+
+template<TS> void foo() {}
+template<int> void foo() {}
+
+void test() { foo<2>(); }