1 files changed, 39 insertions, 14 deletions

diff --git a/gcc/varasm.c b/gcc/varasm.c
index 2a8fb11..d7f8611 100644
--- a/gcc/varasm.c
+++ b/gcc/varasm.c
@@ -5369,20 +5369,7 @@ globalize_decl (tree decl)
   targetm.asm_out.globalize_decl_name (asm_out_file, decl);
 }
 
-/* We have to be able to tell cgraph about the needed-ness of the target
-   of an alias.  This requires that the decl have been defined.  Aliases
-   that precede their definition have to be queued for later processing.  */
-
-typedef struct GTY(()) alias_pair {
-  tree decl;
-  tree target;
-} alias_pair;
-
-/* Define gc'd vector type.  */
-DEF_VEC_O(alias_pair);
-DEF_VEC_ALLOC_O(alias_pair,gc);
-
-static GTY(()) VEC(alias_pair,gc) *alias_pairs;
+VEC(alias_pair,gc) *alias_pairs;
 
 /* Given an assembly name, find the decl it is associated with.  At the
    same time, mark it needed for cgraph.  */
@@ -5526,6 +5513,39 @@ do_assemble_alias (tree decl, tree target)
 #endif
 }
 
+
+/* Remove the alias pairing for functions that are no longer in the call
+   graph.  */
+
+void
+remove_unreachable_alias_pairs (void)
+{
+  unsigned i;
+  alias_pair *p;
+
+  if (alias_pairs == NULL)
+    return;
+
+  for (i = 0; VEC_iterate (alias_pair, alias_pairs, i, p); )
+    {
+      if (!DECL_EXTERNAL (p->decl))
+	{
+	  struct cgraph_node *fnode = NULL;
+	  struct varpool_node *vnode = NULL;
+	  fnode = cgraph_node_for_asm (p->target);
+	  vnode = (fnode == NULL) ? varpool_node_for_asm (p->target) : NULL;
+	  if (fnode == NULL && vnode == NULL)
+	    {
+	      VEC_unordered_remove (alias_pair, alias_pairs, i);
+	      continue;
+	    }
+	}
+
+      i++;
+    }
+}
+
+
 /* First pass of completing pending aliases.  Make sure that cgraph knows
    which symbols will be required.  */
 
@@ -5547,6 +5567,11 @@ finish_aliases_1 (void)
 		   p->decl, p->target);
 	}
       else if (DECL_EXTERNAL (target_decl)
+ 	       /* We use local aliases for C++ thunks to force the tailcall
+ 		  to bind locally.  Of course this is a hack - to keep it
+ 		  working do the following (which is not strictly correct).  */
+ 	       && (! TREE_CODE (target_decl) == FUNCTION_DECL
+ 		   || ! TREE_STATIC (target_decl))
 	       && ! lookup_attribute ("weakref", DECL_ATTRIBUTES (p->decl)))
 	error ("%q+D aliased to external symbol %qE",
 	       p->decl, p->target);