(C++) vtable linkage patch

[Jason Merrill <jason at cygnus dot com>]

Yes, kids, it's time for the latest installment in the long-running saga of
trying to get vtable linkage right!  We were calling repo_template_used
after we had already decided not to emit the vtable for a class.  This
patch simplifies things by delaying the decision until the last minute.

Fixes g++.pt/instantiate4.C.  Applied.

1998-10-28  Jason Merrill  <jason@yorick.cygnus.com>

	* class.c (build_vtable): Don't pass at_eof to import_export_vtable.
	(prepare_fresh_vtable): Likewise.
	(finish_struct_1): Don't call import_export_class.
	* decl2.c (finish_vtable_vardecl): Do import/export stuff.
	(finish_prevtable_vardecl): Lose.
	(finish_file): Don't call it.
	* pt.c (instantiate_class_template): Likewise.

Index: class.c
===================================================================
RCS file: /egcs/carton/cvsfiles/egcs/gcc/cp/class.c,v
retrieving revision 1.101
diff -c -p -r1.101 class.c
*** class.c	1998/10/28 01:53:43	1.101
--- class.c	1998/10/29 04:14:28
*************** build_vtable (binfo, type)
*** 717,723 ****
  #endif
  
    /* Set TREE_PUBLIC and TREE_EXTERN as appropriate.  */
!   import_export_vtable (decl, type, at_eof);
  
    decl = pushdecl_top_level (decl);
    SET_IDENTIFIER_GLOBAL_VALUE (name, decl);
--- 717,723 ----
  #endif
  
    /* Set TREE_PUBLIC and TREE_EXTERN as appropriate.  */
!   import_export_vtable (decl, type, 0);
  
    decl = pushdecl_top_level (decl);
    SET_IDENTIFIER_GLOBAL_VALUE (name, decl);
*************** prepare_fresh_vtable (binfo, for_type)
*** 901,907 ****
  #endif
  
    /* Set TREE_PUBLIC and TREE_EXTERN as appropriate.  */
!   import_export_vtable (new_decl, for_type, at_eof);
  
    if (TREE_VIA_VIRTUAL (binfo))
      my_friendly_assert (binfo == binfo_member (BINFO_TYPE (binfo),
--- 901,907 ----
  #endif
  
    /* Set TREE_PUBLIC and TREE_EXTERN as appropriate.  */
!   import_export_vtable (new_decl, for_type, 0);
  
    if (TREE_VIA_VIRTUAL (binfo))
      my_friendly_assert (binfo == binfo_member (BINFO_TYPE (binfo),
*************** finish_struct_1 (t, warn_anon)
*** 4042,4052 ****
      max_has_virtual = has_virtual;
    if (max_has_virtual > 0)
      TYPE_VIRTUAL_P (t) = 1;
- 
-   /* Do this here before we start messing with vtables so that we are ready
-      for import_export_vtable.  */
-   if (at_eof)
-     import_export_class (t);
  
    if (flag_rtti && TYPE_VIRTUAL_P (t) && !pending_hard_virtuals)
      modify_all_vtables (t, NULL_TREE, NULL_TREE);
--- 4042,4047 ----
Index: decl2.c
===================================================================
RCS file: /egcs/carton/cvsfiles/egcs/gcc/cp/decl2.c,v
retrieving revision 1.150
diff -c -p -r1.150 decl2.c
*** decl2.c	1998/10/28 01:53:46	1.150
--- decl2.c	1998/10/29 04:14:29
*************** import_export_class (ctype)
*** 2578,2593 ****
      }
  }
      
- int
- finish_prevtable_vardecl (prev, vars)
-      tree prev ATTRIBUTE_UNUSED, vars;
- {
-   tree ctype = DECL_CONTEXT (vars);
-   import_export_class (ctype);
-   import_export_vtable (vars, ctype, 1);
-   return 1;
- }
- 
  /* We need to describe to the assembler the relationship between
     a vtable and the vtable of the parent class.  */
  
--- 2578,2583 ----
*************** static int
*** 2619,2624 ****
--- 2609,2618 ----
  finish_vtable_vardecl (prev, vars)
       tree prev, vars;
  {
+   tree ctype = DECL_CONTEXT (vars);
+   import_export_class (ctype);
+   import_export_vtable (vars, ctype, 1);
+ 
    if (! DECL_EXTERNAL (vars)
        && (DECL_INTERFACE_KNOWN (vars)
  	  || TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (vars))
*************** finish_file ()
*** 3351,3361 ****
    SET_DECL_ARTIFICIAL (vars);
    pushdecl (vars);
  #endif
- 
-   /* Walk to mark the inline functions we need, then output them so
-      that we can pick up any other tdecls that those routines need.  */
-   walk_vtables ((void (*) PROTO ((tree, tree))) 0,
- 		finish_prevtable_vardecl);
  
    for (vars = static_aggregates; vars; vars = TREE_CHAIN (vars))
      if (! TREE_ASM_WRITTEN (TREE_VALUE (vars)))
--- 3345,3350 ----
Index: pt.c
===================================================================
RCS file: /egcs/carton/cvsfiles/egcs/gcc/cp/pt.c,v
retrieving revision 1.224
diff -c -p -r1.224 pt.c
*** pt.c	1998/10/28 11:46:03	1.224
--- pt.c	1998/10/29 04:14:29
*************** instantiate_class_template (type)
*** 4736,4743 ****
    CLASSTYPE_GOT_SEMICOLON (type) = 1;
  
    repo_template_used (type);
-   if (at_eof && TYPE_BINFO_VTABLE (type) != NULL_TREE)
-     finish_prevtable_vardecl (NULL, TYPE_BINFO_VTABLE (type));
  
   end:
    TYPE_BEING_DEFINED (type) = 0;
--- 4736,4741 ----