From a9410b4fe946b3f82ff2254b46ef53573897d68e Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Wed, 21 Dec 2016 14:38:35 -0500
Subject: [PATCH] Check that a partial specialization is more specialized.

	* pt.c (process_partial_specialization): Use
	get_partial_spec_bindings to check that the partial specialization
	is more specialized than the primary template.

From-SVN: r243868
---
 gcc/cp/ChangeLog                             |  4 ++++
 gcc/cp/pt.c                                  | 11 +++++++++++
 gcc/testsuite/g++.dg/cpp0x/constexpr-data2.C |  2 +-
 gcc/testsuite/g++.dg/cpp0x/variadic82.C      |  4 ++--
 gcc/testsuite/g++.dg/cpp0x/variadic83.C      |  4 ++--
 gcc/testsuite/g++.dg/template/partial5.C     |  2 +-
 6 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 4c68b1e4e3e..7faac155e34 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,9 @@
 2016-12-21  Jason Merrill  <jason@redhat.com>
 
+	* pt.c (process_partial_specialization): Use
+	get_partial_spec_bindings to check that the partial specialization
+	is more specialized than the primary template.
+
 	* pt.c (convert_template_argument): Pass args to do_auto_deduction.
 	(mark_template_parm): Handle deducibility from type of non-type
 	argument here.
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 9d9c35e47e6..8abbcfb6f43 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -4606,9 +4606,20 @@ process_partial_specialization (tree decl)
 	     "primary template because it replaces multiple parameters "
 	     "with a pack expansion");
       inform (DECL_SOURCE_LOCATION (maintmpl), "primary template here");
+      /* Avoid crash in process_partial_specialization.  */
       return decl;
     }
 
+  /* If we aren't in a dependent class, we can actually try deduction.  */
+  else if (tpd.level == 1
+	   && !get_partial_spec_bindings (maintmpl, maintmpl, specargs))
+    {
+      if (permerror (input_location, "partial specialization %qD is not "
+		     "more specialized than", decl))
+	inform (DECL_SOURCE_LOCATION (maintmpl), "primary template %qD",
+		maintmpl);
+    }
+
   /* [temp.class.spec]
 
      A partially specialized non-type argument expression shall not
diff --git a/gcc/testsuite/g++.dg/cpp0x/constexpr-data2.C b/gcc/testsuite/g++.dg/cpp0x/constexpr-data2.C
index 312760a3767..898102167de 100644
--- a/gcc/testsuite/g++.dg/cpp0x/constexpr-data2.C
+++ b/gcc/testsuite/g++.dg/cpp0x/constexpr-data2.C
@@ -12,7 +12,7 @@ template<typename _Tp, _Tp v>
   };
 
 // Partial specialization.
-template<typename _Tp, _Tp v>
+template<typename _Tp, _Tp* v>
   struct A3<_Tp*, v>
   {
     typedef _Tp* value_type;
diff --git a/gcc/testsuite/g++.dg/cpp0x/variadic82.C b/gcc/testsuite/g++.dg/cpp0x/variadic82.C
index f9bbc353268..9ac59cd5f41 100644
--- a/gcc/testsuite/g++.dg/cpp0x/variadic82.C
+++ b/gcc/testsuite/g++.dg/cpp0x/variadic82.C
@@ -3,9 +3,9 @@
 
 template<typename> struct A;
 
-template<typename... T> struct A<T*...> // { dg-bogus "cannot expand" "" }
+template<typename... T> struct A<T*...> // { dg-error "" }
 {
   struct B;
 };
 
-A<void*> a; // { dg-bogus "incomplete type" "" }
+A<void*> a;
diff --git a/gcc/testsuite/g++.dg/cpp0x/variadic83.C b/gcc/testsuite/g++.dg/cpp0x/variadic83.C
index 507fc7e4c6c..c751e7327ca 100644
--- a/gcc/testsuite/g++.dg/cpp0x/variadic83.C
+++ b/gcc/testsuite/g++.dg/cpp0x/variadic83.C
@@ -3,6 +3,6 @@
 
 template<typename> struct A;
 
-template<typename... T> struct A<T...> { }; // { dg-bogus "cannot expand" "" }
+template<typename... T> struct A<T...> { }; // { dg-error "" }
 
-A<int> a; // { dg-bogus "incomplete type" "" }
+A<int> a;
diff --git a/gcc/testsuite/g++.dg/template/partial5.C b/gcc/testsuite/g++.dg/template/partial5.C
index 2f400f7d44c..1b56fb39fa1 100644
--- a/gcc/testsuite/g++.dg/template/partial5.C
+++ b/gcc/testsuite/g++.dg/template/partial5.C
@@ -14,7 +14,7 @@ template<typename T, typename T::foo V>
 struct Y { };
 
 template<typename T, typename U, U v>
-struct Y<T, v> { }; // { dg-error "not deducible|U" "" { target { ! c++1z } } }
+struct Y<T, v> { }; // { dg-error "" }
 
 
 template<typename T, T V>
-- 
2.30.2