From 77adef8498fb09947e889abbacb1d2bd8ece0929 Mon Sep 17 00:00:00 2001
From: Mark Mitchell <mark@codesourcery.com>
Date: Tue, 23 Apr 2002 08:37:23 +0000
Subject: [PATCH] re PR c++/6256 (Seg fault for template friends in namespaces,
 regression from 2.95)

	PR c++/6256:
	* pt.c (tsubst_friend_class): Handle templates with explicit
	nested names.

	PR c++/6331:
	* typeck.c (merge_types): Remember the cv-qualification of pointer
	types when merging them.

	PR c++/6256:
	* g++.dg/template/friend5.C: New test.

	PR c++/6331:
	* g++.dg/template/qual1.C: Likewise.

From-SVN: r52661
---
 gcc/cp/ChangeLog                        | 10 +++++++
 gcc/cp/pt.c                             | 35 ++++++++++++++-----------
 gcc/cp/typeck.c                         |  2 ++
 gcc/testsuite/ChangeLog                 |  8 ++++++
 gcc/testsuite/g++.dg/template/friend5.C |  9 +++++++
 gcc/testsuite/g++.dg/template/qual1.C   | 21 +++++++++++++++
 6 files changed, 70 insertions(+), 15 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/template/friend5.C
 create mode 100644 gcc/testsuite/g++.dg/template/qual1.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 67c67b8682e..f7ac920401b 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,13 @@
+2002-04-23  Mark Mitchell  <mark@codesourcery.com>
+
+	PR c++/6256:
+	* pt.c (tsubst_friend_class): Handle templates with explicit
+	nested names.
+
+	PR c++/6331:
+	* typeck.c (merge_types): Remember the cv-qualification of pointer
+	types when merging them.
+
 2002-04-20  Neil Booth  <neil@daikokuya.demon.co.uk>
 
 	* cp-lang.c (LANG_HOOKS_FUNCTION_INIT,
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index aa198a68fbe..39c6bf695b3 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -4833,23 +4833,28 @@ tsubst_friend_class (friend_tmpl, args)
   tree tmpl;
 
   /* First, we look for a class template.  */
-  tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0); 
-  
-  /* But, if we don't find one, it might be because we're in a
-     situation like this:
+  if (DECL_CONTEXT (friend_tmpl))
+    tmpl = friend_tmpl;
+  else
+    {
+      tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0); 
 
-       template <class T>
-       struct S {
-         template <class U>
-	 friend struct S;
-       };
+      /* But, if we don't find one, it might be because we're in a
+	 situation like this:
 
-     Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
-     for `S<int>', not the TEMPLATE_DECL.  */
-  if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
-    {
-      tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
-      tmpl = maybe_get_template_decl_from_type_decl (tmpl);
+	   template <class T>
+	   struct S {
+	     template <class U>
+	     friend struct S;
+	   };
+
+	 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
+	 for `S<int>', not the TEMPLATE_DECL.  */
+      if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
+	{
+	  tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
+	  tmpl = maybe_get_template_decl_from_type_decl (tmpl);
+	}
     }
 
   if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index a92813528a3..690df764bf5 100644
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -592,12 +592,14 @@ merge_types (t1, t2)
       /* For two pointers, do this recursively on the target type.  */
       {
 	tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
+	int quals = cp_type_quals (t1);
 
 	if (code1 == POINTER_TYPE)
 	  t1 = build_pointer_type (target);
 	else
 	  t1 = build_reference_type (target);
 	t1 = build_type_attribute_variant (t1, attributes);
+	t1 = cp_build_qualified_type (t1, quals);
 
 	if (TREE_CODE (target) == METHOD_TYPE)
 	  t1 = build_ptrmemfunc_type (t1);
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index ca26c2f1d60..3c4635a06af 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2002-04-23  Mark Mitchell  <mark@codesourcery.com>
+
+	PR c++/6256:
+	* g++.dg/template/friend5.C: New test.
+
+	PR c++/6331:
+	* g++.dg/template/qual1.C: Likewise.
+
 2002-04-22  Zack Weinberg  <zack@codesourcery.com>
 
 	* gcc.c-torture/execute/980707-1.c: Don't use isspace().
diff --git a/gcc/testsuite/g++.dg/template/friend5.C b/gcc/testsuite/g++.dg/template/friend5.C
new file mode 100644
index 00000000000..1a63e71e32c
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/friend5.C
@@ -0,0 +1,9 @@
+// { dg-do compile }
+
+namespace NS {  template <typename number> class C;  }
+
+template <typename T> class X {
+    template <typename N> friend class NS::C;
+};
+
+template class X<int>;
diff --git a/gcc/testsuite/g++.dg/template/qual1.C b/gcc/testsuite/g++.dg/template/qual1.C
new file mode 100644
index 00000000000..3d512c1e1be
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/qual1.C
@@ -0,0 +1,21 @@
+// { dg-do compile }
+
+template<class T>
+class Link_array
+{
+public:
+  void sort (int (*compare) (T *const&,T *const&));
+};
+
+int shift_compare (int *const &, int *const &) {};
+
+template<class T> void
+Link_array<T>::sort (int (*compare) (T *const&,T *const&)) 
+{
+}
+
+void f ()
+{
+  Link_array<int> clashes;
+  clashes.sort (shift_compare);
+}
-- 
2.30.2