From 195584ff788e48c111a2613104bb968f0b6bc527 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Wed, 19 May 2010 11:44:08 -0400
Subject: [PATCH] re PR c++/44193 (function types, cv-quals and typename)

	PR c++/44193
	* pt.c (tsubst) [TYPENAME_TYPE]: Discard cv-quals on
	function/reference type.

From-SVN: r159575
---
 gcc/cp/ChangeLog                          |  6 ++++++
 gcc/cp/pt.c                               | 12 +++++++++--
 gcc/testsuite/ChangeLog                   |  5 +++++
 gcc/testsuite/g++.dg/template/fntype1.C   | 26 +++++++++++++++++++++++
 gcc/testsuite/g++.dg/template/qualttp20.C |  2 +-
 5 files changed, 48 insertions(+), 3 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/template/fntype1.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 5b891c00a883..df69a8ec077e 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2010-05-19  Jason Merrill  <jason@redhat.com>
+
+	PR c++/44193
+	* pt.c (tsubst) [TYPENAME_TYPE]: Discard cv-quals on
+	function/reference type.
+
 2010-04-20  Richard Guenther  <rguenther@suse.de>
 
 	Backport from mainline
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 46866c030485..434e0cf8bfff 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -9411,6 +9411,7 @@ tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
 				     in_decl, /*entering_scope=*/1);
 	tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
 			      complain, in_decl);
+	int quals;
 
 	if (ctx == error_mark_node || f == error_mark_node)
 	  return error_mark_node;
@@ -9460,8 +9461,15 @@ tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
 		     t, f);
 	  }
 
-	return cp_build_qualified_type_real
-	  (f, cp_type_quals (f) | cp_type_quals (t), complain);
+	/* cv-quals from the template are discarded when
+	   substituting in a function or reference type.  */
+	if (TREE_CODE (f) == FUNCTION_TYPE
+	    || TREE_CODE (f) == METHOD_TYPE
+	    || TREE_CODE (f) == REFERENCE_TYPE)
+	  quals = cp_type_quals (f);
+	else
+	  quals = cp_type_quals (f) | cp_type_quals (t);
+	return cp_build_qualified_type_real (f, quals, complain);
       }
 
     case UNBOUND_CLASS_TEMPLATE:
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 93a89110b605..d5955128b94a 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2010-05-19  Jason Merrill  <jason@redhat.com>
+
+	PR c++/44193
+	* g++.dg/template/fntype1.C: New.
+
 2010-04-30  DJ Delorie  <dj@redhat.com>
 
 	* gcc.c-torture/execute/20100430-1.c: New test.
diff --git a/gcc/testsuite/g++.dg/template/fntype1.C b/gcc/testsuite/g++.dg/template/fntype1.C
new file mode 100644
index 000000000000..d7be273aa421
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/fntype1.C
@@ -0,0 +1,26 @@
+bool f(int i) { return i != 5; }
+
+template <class X, class P = bool(X)>
+struct Traits
+{
+ typedef P type;
+};
+
+template <class X, class P = typename Traits<X>::type>
+struct S
+{
+ const P& p_;
+ S( const P& p ) : p_(p) {} // const reference
+};
+
+template <class X>
+S<X> make_s(const typename Traits<X>::type & p) // const reference
+{
+ return S<X>(p); // << HERE
+}
+
+
+int main()
+{
+ make_s<int>(f);
+}
diff --git a/gcc/testsuite/g++.dg/template/qualttp20.C b/gcc/testsuite/g++.dg/template/qualttp20.C
index ae20d7629020..ea581db54465 100644
--- a/gcc/testsuite/g++.dg/template/qualttp20.C
+++ b/gcc/testsuite/g++.dg/template/qualttp20.C
@@ -17,7 +17,7 @@ struct AS
 template <typename T> struct B1 : T
 {
   typedef typename T::L __restrict__ r;// { dg-error "'__restrict__' qualifiers cannot" "" }
-  typedef typename T::myT __restrict__ p;// { dg-error "ignoring '__restrict__'" }
+  typedef typename T::myT __restrict__ p;
 
   // The following are DR 295 dependent
   typedef typename T::myT volatile *myvolatile;
-- 
2.47.2