From 554add142ef75ff6f032040ea4743f05ccfb442a Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Fri, 23 Mar 2018 08:57:09 -0400
Subject: [PATCH] PR c++/78489 - Substitution in wrong order

	PR c++/84489
	* pt.c (type_unification_real): Revert last two changes.

From-SVN: r258802
---
 gcc/cp/ChangeLog                           |  6 ++++++
 gcc/cp/pt.c                                | 10 ++--------
 gcc/testsuite/g++.dg/cpp0x/alias-decl-63.C | 18 ------------------
 gcc/testsuite/g++.dg/cpp0x/fntmpdefarg7.C  | 10 ----------
 4 files changed, 8 insertions(+), 36 deletions(-)
 delete mode 100644 gcc/testsuite/g++.dg/cpp0x/alias-decl-63.C
 delete mode 100644 gcc/testsuite/g++.dg/cpp0x/fntmpdefarg7.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 527ed0e4aded..6e1648fb4a94 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2018-03-23  Jason Merrill  <jason@redhat.com>
+
+	PR c++/78489 - Substitution in wrong order
+	PR c++/84489
+	* pt.c (type_unification_real): Revert last two changes.
+
 2018-03-09  Jason Merrill  <jason@redhat.com>
 
 	PR c++/84785 - ICE with alias template and default targs.
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 423d92c66f46..9dbf17ba4d88 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -18602,17 +18602,11 @@ type_unification_real (tree tparms,
 	  location_t save_loc = input_location;
 	  if (DECL_P (parm))
 	    input_location = DECL_SOURCE_LOCATION (parm);
-
-	  if (saw_undeduced == 1)
-	    ++processing_template_decl;
 	  arg = tsubst_template_arg (arg, targs, complain, NULL_TREE);
-	  if (saw_undeduced == 1)
-	    --processing_template_decl;
-
-	  if (arg != error_mark_node && !uses_template_parms (arg))
+	  if (!uses_template_parms (arg))
 	    arg = convert_template_argument (parm, arg, targs, complain,
 					     i, NULL_TREE);
-	  else if (saw_undeduced == 1)
+	  else if (saw_undeduced < 2)
 	    arg = NULL_TREE;
 	  else
 	    arg = error_mark_node;
diff --git a/gcc/testsuite/g++.dg/cpp0x/alias-decl-63.C b/gcc/testsuite/g++.dg/cpp0x/alias-decl-63.C
deleted file mode 100644
index 04fb42d9e091..000000000000
--- a/gcc/testsuite/g++.dg/cpp0x/alias-decl-63.C
+++ /dev/null
@@ -1,18 +0,0 @@
-// PR c++/84785
-// { dg-do compile { target c++11 } }
-
-template <typename> struct A;
-template <bool> struct B;
-template <bool B, typename> using enable_if_t = typename B<B>::type;
-template <long> using type_pack_element = int;
-struct variant {
-  variant() {}
-  template <typename Arg, long I = Arg::type::value,
-            typename = type_pack_element<I>, enable_if_t<A<Arg>::value, int>>
-  variant(Arg &&);
-};
-
-struct S {
-  variant var;
-};
-int main() { S s; }
diff --git a/gcc/testsuite/g++.dg/cpp0x/fntmpdefarg7.C b/gcc/testsuite/g++.dg/cpp0x/fntmpdefarg7.C
deleted file mode 100644
index 636bf1afd883..000000000000
--- a/gcc/testsuite/g++.dg/cpp0x/fntmpdefarg7.C
+++ /dev/null
@@ -1,10 +0,0 @@
-// PR c++/84489
-// { dg-do compile { target c++11 } }
-
-template <class T = int, T N = T(), bool B = (N >> 1)>
-T f1() {return 0;}
-
-int main()
-{
-  f1(); // Bug here
-}
-- 
2.47.2