Re: ipa-visibility TLC 2/n

[Jan Hubicka]

Hi,
this is the last part.  It makes DECL_VIRTUAL to be copied when creating 
aliases.  This is
needed to make sanity check in gimple-fold happy (it checks that vtables are 
DECL_VIRTUAL).
It also resets initializers of aliases to save memory.

Bootstrapped/regtested rs6000-aix, comitted.

Index: symtab.c
===================================================================
--- symtab.c    (revision 211357)
+++ symtab.c    (working copy)
@@ -1154,7 +1154,9 @@
   TREE_PUBLIC (new_decl) = 0;
   DECL_COMDAT (new_decl) = 0;
   DECL_WEAK (new_decl) = 0;
-  DECL_VIRTUAL_P (new_decl) = 0;
+
+  /* Since the aliases can be added to vtables, keep DECL_VIRTUAL flag.  */
+  DECL_VIRTUAL_P (new_decl) = DECL_VIRTUAL_P (node->decl);
   if (TREE_CODE (new_decl) == FUNCTION_DECL)
     {
       DECL_STATIC_CONSTRUCTOR (new_decl) = 0;
@@ -1165,6 +1167,7 @@
   else
     {
       TREE_READONLY (new_decl) = TREE_READONLY (node->decl);
+      DECL_INITIAL (new_decl) = error_mark_node;
       new_node = varpool_create_variable_alias (new_decl, node->decl);
     }
   symtab_resolve_alias (new_node, node);