[C++ PATCH] Fix PR8389

[C++ PATCH] Fix PR8389

[Kriang Lerdsuwanakij]

Hi

The appended patch fixes PR 8389.  This is a regression in the
main trunk caused by the enforcement of typename access checking
a couple months ago.  There are a few missed cases.  In particular,
inside "instantiate_template" and "get_mostly_instantiated_function_type"
functions, "current_class_type" is not properly set up when we are
tsubst'ing member functions.  This is fixed by the patch.

The patch also simplify the function get_mostly_instantiated_function_type
a bit.  The CONTEXTP and TPARMSP parameters are never used by the callers
so they are removed.  Also, the tsubst call for the function context is
not required.  It's the same for a fully instantiated DECL (with N levels
of template arguments), and a partially instantiated N-1 levels of
arguments.

Bootstrapped and tested on i686-pc-linux-gnu with no regressions.
OK to commit to main trunk?

--Kriang


2002-11-08  Kriang Lerdsuwanakij  <lerdsuwa@users.sourceforge.net>

	PR c++/8389
	* pt.c (instantiate_template): Push class scope for member
	functions.
	(get_mostly_instantiated_function_type): Likewise.  Don't call
	tsubst on context.  Remove CONTEXTP and TPARMSP parameters.
	* cp-tree.h (get_mostly_instantiated_function_type): Adjust.
	* mangle.c (write_encoding, write_unqualified_name): Adjust.

2002-11-08  Kriang Lerdsuwanakij  <lerdsuwa@users.sourceforge.net>

	PR c++/8389
	* g++.dg/template/access6.C: New test.


diff -cprN gcc-main-save/gcc/cp/cp-tree.h gcc-main-new/gcc/cp/cp-tree.h
*** gcc-main-save/gcc/cp/cp-tree.h	Wed Oct 30 22:49:01 2002
--- gcc-main-new/gcc/cp/cp-tree.h	Fri Nov  8 11:39:15 2002
*************** extern void print_candidates
*** 4010,4016 ****
   extern int instantiate_pending_templates        PARAMS ((void));
   extern tree tsubst_default_argument             PARAMS ((tree, tree, tree));
   extern tree most_general_template		PARAMS ((tree));
! extern tree get_mostly_instantiated_function_type PARAMS ((tree, tree *, tree *));
   extern int problematic_instantiation_changed    PARAMS ((void));
   extern void record_last_problematic_instantiation PARAMS ((void));
   extern tree current_instantiation               PARAMS ((void));
--- 4010,4016 ----
   extern int instantiate_pending_templates        PARAMS ((void));
   extern tree tsubst_default_argument             PARAMS ((tree, tree, tree));
   extern tree most_general_template		PARAMS ((tree));
! extern tree get_mostly_instantiated_function_type PARAMS ((tree));
   extern int problematic_instantiation_changed    PARAMS ((void));
   extern void record_last_problematic_instantiation PARAMS ((void));
   extern tree current_instantiation               PARAMS ((void));
diff -cprN gcc-main-save/gcc/cp/mangle.c gcc-main-new/gcc/cp/mangle.c
*** gcc-main-save/gcc/cp/mangle.c	Fri Oct 18 22:29:12 2002
--- gcc-main-new/gcc/cp/mangle.c	Fri Nov  8 11:39:03 2002
*************** write_encoding (decl)
*** 656,662 ****
         tree fn_type;

         if (decl_is_template_id (decl, NULL))
! 	fn_type = get_mostly_instantiated_function_type (decl, NULL, NULL);
         else
   	fn_type = TREE_TYPE (decl);

--- 656,662 ----
         tree fn_type;

         if (decl_is_template_id (decl, NULL))
! 	fn_type = get_mostly_instantiated_function_type (decl);
         else
   	fn_type = TREE_TYPE (decl);

*************** write_unqualified_name (decl)
*** 1011,1018 ****
         tree type;
         if (decl_is_template_id (decl, NULL))
   	{
! 	  tree fn_type = get_mostly_instantiated_function_type (decl, NULL,
! 								NULL);
   	  type = TREE_TYPE (fn_type);
   	}
         else
--- 1011,1017 ----
         tree type;
         if (decl_is_template_id (decl, NULL))
   	{
! 	  tree fn_type = get_mostly_instantiated_function_type (decl);
   	  type = TREE_TYPE (fn_type);
   	}
         else
diff -cprN gcc-main-save/gcc/cp/pt.c gcc-main-new/gcc/cp/pt.c
*** gcc-main-save/gcc/cp/pt.c	Wed Oct 30 22:49:01 2002
--- gcc-main-new/gcc/cp/pt.c	Fri Nov  8 15:48:35 2002
*************** instantiate_template (tmpl, targ_ptr)
*** 7756,7764 ****
--- 7756,7774 ----
   	}
       }

+   /* Make sure that we can see identifiers, and compute access
+      correctly.  */
+   if (DECL_CLASS_SCOPE_P (gen_tmpl))
+     pushclass (tsubst (DECL_CONTEXT (gen_tmpl), targ_ptr, tf_error,
+ 		       gen_tmpl), 1);
+
     /* substitute template parameters */
     fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
   		   targ_ptr, tf_error, gen_tmpl);
+
+   if (DECL_CLASS_SCOPE_P (gen_tmpl))
+     popclass ();
+
     /* The DECL_TI_TEMPLATE should always be the immediate parent
        template, not the most general template.  */
     DECL_TI_TEMPLATE (fndecl) = tmpl;
*************** tsubst_enum (tag, newtag, args)
*** 10384,10401 ****
   /* DECL is a FUNCTION_DECL that is a template specialization.  Return
      its type -- but without substituting the innermost set of template
      arguments.  So, innermost set of template parameters will appear in
!    the type.  If CONTEXTP is non-NULL, then the partially substituted
!    DECL_CONTEXT (if any) will also be filled in.  Similarly, TPARMSP
!    will be filled in with the substituted template parameters, if it
!    is non-NULL.  */

   tree
! get_mostly_instantiated_function_type (decl, contextp, tparmsp)
        tree decl;
-      tree *contextp;
-      tree *tparmsp;
   {
-   tree context = NULL_TREE;
     tree fn_type;
     tree tmpl;
     tree targs;
--- 10394,10405 ----
   /* DECL is a FUNCTION_DECL that is a template specialization.  Return
      its type -- but without substituting the innermost set of template
      arguments.  So, innermost set of template parameters will appear in
!    the type.  */

   tree
! get_mostly_instantiated_function_type (decl)
        tree decl;
   {
     tree fn_type;
     tree tmpl;
     tree targs;
*************** get_mostly_instantiated_function_type (d
*** 10412,10419 ****
     my_friendly_assert (parm_depth == TMPL_ARGS_DEPTH (targs), 0);

     fn_type = TREE_TYPE (tmpl);
-   if (DECL_STATIC_FUNCTION_P (decl))
-     context = DECL_CONTEXT (decl);

     if (parm_depth == 1)
       /* No substitution is necessary.  */
--- 10416,10421 ----
*************** get_mostly_instantiated_function_type (d
*** 10433,10443 ****
   			   TMPL_ARGS_DEPTH (targs),
   			   make_tree_vec (DECL_NTPARMS (tmpl)));

         /* Now, do the (partial) substitution to figure out the
   	 appropriate function type.  */
         fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
-       if (DECL_STATIC_FUNCTION_P (decl))
- 	context = tsubst (context, partial_args, tf_error, NULL_TREE);

         /* Substitute into the template parameters to obtain the real
   	 innermost set of parameters.  This step is important if the
--- 10435,10451 ----
   			   TMPL_ARGS_DEPTH (targs),
   			   make_tree_vec (DECL_NTPARMS (tmpl)));

+       /* Make sure that we can see identifiers, and compute access
+ 	 correctly.  We can just use the context of DECL for the
+ 	 partial substitution here.  It depends only on outer template
+ 	 parameters, regardless of whether the innermost level is
+ 	 specialized or not.  */
+       if (DECL_CLASS_SCOPE_P (decl))
+ 	pushclass (DECL_CONTEXT (decl), 1);
+
         /* Now, do the (partial) substitution to figure out the
   	 appropriate function type.  */
         fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);

         /* Substitute into the template parameters to obtain the real
   	 innermost set of parameters.  This step is important if the
*************** get_mostly_instantiated_function_type (d
*** 10445,10456 ****
   	 parameters whose types depend on outer template parameters.  */
         TREE_VEC_LENGTH (partial_args)--;
         tparms = tsubst_template_parms (tparms, partial_args, tf_error);
-     }

!   if (contextp)
!     *contextp = context;
!   if (tparmsp)
!     *tparmsp = tparms;

     return fn_type;
   }
--- 10453,10462 ----
   	 parameters whose types depend on outer template parameters.  */
         TREE_VEC_LENGTH (partial_args)--;
         tparms = tsubst_template_parms (tparms, partial_args, tf_error);

!       if (DECL_CLASS_SCOPE_P (decl))
! 	popclass ();
!     }

     return fn_type;
   }
diff -cprN gcc-main-save/gcc/testsuite/g++.dg/template/access6.C gcc-main-new/gcc/testsuite/g++.dg/template/access6.C
*** gcc-main-save/gcc/testsuite/g++.dg/template/access6.C	Thu Jan  1 07:00:00 1970
--- gcc-main-new/gcc/testsuite/g++.dg/template/access6.C	Thu Nov  7 22:37:11 2002
***************
*** 0 ****
--- 1,17 ----
+ // { dg-do compile }
+ // Origin: Detlef Vollmann <dv@vollmann.ch>
+
+ // PR c++/8389
+ // Access control ICE for typename during instantiation and name mangling
+
+ template <class> class Base {
+   protected:
+     typedef int Type;
+ };
+
+ template <class T> struct Derived : public Base<T> {
+   typedef typename Base<T>::Type Type;
+   template <class Arg> void f(Type = Type()) {};
+ };
+
+ template void Derived<char>::f<int> (Type);

Re: [C++ PATCH] Fix PR8389

[Mark Mitchell]

--On Friday, November 08, 2002 04:04:48 PM +0700 Kriang Lerdsuwanakij 
<lerdsuwa@users.sourceforge.net> wrote:

> Hi
>
> The appended patch fixes PR 8389.  This is a regression in the
> main trunk caused by the enforcement of typename access checking
> a couple months ago.  There are a few missed cases.  In particular,
> inside "instantiate_template" and "get_mostly_instantiated_function_type"
> functions, "current_class_type" is not properly set up when we are
> tsubst'ing member functions.  This is fixed by the patch.

OK; thanks.

-- 
Mark Mitchell                mark@codesourcery.com
CodeSourcery, LLC            http://www.codesourcery.com