From 5675808f5c0b9a91dfea8543828fa1c236b6467f Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Fri, 11 Aug 2017 01:35:39 -0400
Subject: [PATCH] PR c++/81671 - nullptr_t template parameter

	* pt.c (convert_nontype_argument): Fix nullptr_t check.

From-SVN: r251046
---
 gcc/cp/ChangeLog                       |  5 +++++
 gcc/cp/pt.c                            |  2 +-
 gcc/testsuite/g++.dg/cpp0x/nullptr39.C | 15 +++++++++++++++
 3 files changed, 21 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp0x/nullptr39.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 792a42ad14a..0115f68cde6 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,8 @@
+2017-08-11  Jason Merrill  <jason@redhat.com>
+
+	PR c++/81671 - nullptr_t template parameter
+	* pt.c (convert_nontype_argument): Fix nullptr_t check.
+
 2017-08-10  Jason Merrill  <jason@redhat.com>
 
 	PR c++/81359 - Unparsed NSDMI error from SFINAE context.
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 0f899b9edec..bf1f75de1e7 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -6879,7 +6879,7 @@ convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain)
     }
   else if (NULLPTR_TYPE_P (type))
     {
-      if (expr != nullptr_node)
+      if (!NULLPTR_TYPE_P (TREE_TYPE (expr)))
 	{
 	  if (complain & tf_error)
 	    error ("%qE is not a valid template argument for type %qT "
diff --git a/gcc/testsuite/g++.dg/cpp0x/nullptr39.C b/gcc/testsuite/g++.dg/cpp0x/nullptr39.C
new file mode 100644
index 00000000000..a34a6af73e9
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/nullptr39.C
@@ -0,0 +1,15 @@
+// PR c++/81671
+// { dg-do compile { target c++11 } }
+
+namespace std { typedef decltype(nullptr) nullptr_t; }
+
+template<class R, class CB> struct Bar
+{};
+template<class R> struct Bar<R, std::nullptr_t>
+{
+    template<std::nullptr_t> struct Bind { constexpr static int const cb = 0; };
+};
+int foo()
+{
+  return Bar<int, decltype(nullptr)>::Bind<nullptr>::cb;
+}
-- 
2.30.2