C++ PATCH: PR 29105

[Mark Mitchell]

This patch fixes a bug that caused a crash when calling a base class
member template from a derived class template.  The problem was that
we failed to create a baselink, which then confused the call
machinery, which was invoked because the function call in the test
case is non-dependent.

Tested on x86-64-unknown_linux-gnu, applied on the mainline.

--
Mark Mitchell
CodeSourcery
mark@codesourcery.com
(650) 331-3385 x713

2006-10-01  Mark Mitchell  <mark@codesourcery.com>

	PR c++/29105
	* pt.c (tsubst_baselink): Substitute into the qualifying scope.
	* semantics.c (baselink_for_fns): Build a baselink, even when
	processing a template.

2006-10-01  Mark Mitchell  <mark@codesourcery.com>

	PR c++/29105
	* g++.dg/template/member6.C: New test.
	* g++.dg/parse/typename7.C: Adjust error markers.

Index: gcc/cp/pt.c
===================================================================
--- gcc/cp/pt.c	(revision 117359)
+++ gcc/cp/pt.c	(working copy)
@@ -7779,15 +7779,15 @@ tsubst_baselink (tree baselink, tree obj
     tree template_args = 0;
     bool template_id_p = false;
 
-    /* A baselink indicates a function from a base class.  The
-       BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
-       non-dependent types; otherwise, the lookup could not have
-       succeeded.  However, they may indicate bases of the template
-       class, rather than the instantiated class.
-
-       In addition, lookups that were not ambiguous before may be
-       ambiguous now.  Therefore, we perform the lookup again.  */
+    /* A baselink indicates a function from a base class.  Both the
+       BASELINK_ACCESS_BINFO and the base class referenced may
+       indicate bases of the template class, rather than the
+       instantiated class.  In addition, lookups that were not
+       ambiguous before may be ambiguous now.  Therefore, we perform
+       the lookup again.  */
     qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
+    qualifying_scope = tsubst (qualifying_scope, args,
+			       complain, in_decl);
     fns = BASELINK_FUNCTIONS (baselink);
     optype = BASELINK_OPTYPE (baselink);
     if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
Index: gcc/cp/semantics.c
===================================================================
--- gcc/cp/semantics.c	(revision 117359)
+++ gcc/cp/semantics.c	(working copy)
@@ -2400,7 +2400,6 @@ baselink_for_fns (tree fns)
   tree cl;
 
   if (BASELINK_P (fns) 
-      || processing_template_decl
       || error_operand_p (fns))
     return fns;
   
Index: gcc/testsuite/g++.dg/parse/typename7.C
===================================================================
--- gcc/testsuite/g++.dg/parse/typename7.C	(revision 117359)
+++ gcc/testsuite/g++.dg/parse/typename7.C	(working copy)
@@ -11,7 +11,7 @@ struct A
   template<typename T> void bar(T t) {
     this->foo<typename T>(t); } // { dg-error "expected|parse error|no matching" }
   template<typename T> void bad(T t) {
-    foo<typename T>(t); } // { dg-error "expected|parse error" }
+    foo<typename T>(t); } // { dg-error "expected|parse error|no matching" }
 };
 
 template <typename T>
Index: gcc/testsuite/g++.dg/template/member6.C
===================================================================
--- gcc/testsuite/g++.dg/template/member6.C	(revision 0)
+++ gcc/testsuite/g++.dg/template/member6.C	(revision 0)
@@ -0,0 +1,16 @@
+// PR c++/29105
+
+struct Observer
+{
+  template < typename T > void observeComponent ();
+};
+
+template < typename T >
+struct TagFilter : Observer
+{
+  TagFilter ()
+  {
+    observeComponent < int > ();
+  }
+};
+