re PR ipa/65502 (pure-const should play well with clobbers.)

	PR ipa/65502
	* ipa-comdats.c (enqueue_references): Walk through thunks.
	(ipa_comdats): Likewise.
	(set_comdat_group_1): New function.

From-SVN: r221574

gcc/ChangeLog

 2015-03-20  Jan Hubicka  <hubicka@ucw.cz>
 
+	PR ipa/65502
+	* ipa-comdats.c (enqueue_references): Walk through thunks.
+	(ipa_comdats): Likewise.
+	(set_comdat_group_1): New function.
+
+2015-03-20  Jan Hubicka  <hubicka@ucw.cz>
+
 	PR ipa/65475
 	* ipa-devirt.c (add_type_duplicate): Prevail polymorphic type over
 	non-polymorphic

gcc/ipa-comdats.c

@@ -182,6 +182,10 @@ enqueue_references (symtab_node **first,
   for (i = 0; symbol->iterate_reference (i, ref); i++)
     {
       symtab_node *node = ref->referred->ultimate_alias_target ();
+
+      /* Always keep thunks in same sections as target function.  */
+      if (is_a <cgraph_node *>(node))
+	node = dyn_cast <cgraph_node *> (node)->function_symbol ();
       if (!node->aux && node->definition)
 	{
 	   node->aux = *first;
@@ -199,6 +203,10 @@ enqueue_references (symtab_node **first,
 	else
 	  {
 	    symtab_node *node = edge->callee->ultimate_alias_target ();
+
+	    /* Always keep thunks in same sections as target function.  */
+	    if (is_a <cgraph_node *>(node))
+	      node = dyn_cast <cgraph_node *> (node)->function_symbol ();
 	    if (!node->aux && node->definition)
 	      {
 		 node->aux = *first;
@@ -209,7 +217,7 @@ enqueue_references (symtab_node **first,
 }
 
 /* Set comdat group of SYMBOL to GROUP.
-   Callback for symtab_for_node_and_aliases.  */
+   Callback for for_node_and_aliases.  */
 
 bool
 set_comdat_group (symtab_node *symbol,
@@ -223,6 +231,16 @@ set_comdat_group (symtab_node *symbol,
   return false;
 }
 
+/* Set comdat group of SYMBOL to GROUP.
+   Callback for for_node_thunks_and_aliases.  */
+
+bool
+set_comdat_group_1 (cgraph_node *symbol,
+		    void *head_p)
+{
+  return set_comdat_group (symbol, head_p);
+}
+
 /* The actual pass with the main dataflow loop.  */
 
 static unsigned int
@@ -263,7 +281,12 @@ ipa_comdats (void)
 		 && (DECL_STATIC_CONSTRUCTOR (symbol->decl)
 		     || DECL_STATIC_DESTRUCTOR (symbol->decl))))
       {
-	map.put (symbol->ultimate_alias_target (), error_mark_node);
+	symtab_node *target = symbol->ultimate_alias_target ();
+
+	/* Always keep thunks in same sections as target function.  */
+	if (is_a <cgraph_node *>(target))
+	  target = dyn_cast <cgraph_node *> (target)->function_symbol ();
+	map.put (target, error_mark_node);
 
 	/* Mark the symbol so we won't waste time visiting it for dataflow.  */
 	symbol->aux = (symtab_node *) (void *) 1;
@@ -332,10 +355,8 @@ ipa_comdats (void)
       symbol->aux = NULL; 
       if (!symbol->get_comdat_group ()
 	  && !symbol->alias
-	  /* Thunks to external functions do not need to be categorized.  */
 	  && (!(fun = dyn_cast <cgraph_node *> (symbol))
-	      || !fun->thunk.thunk_p
-	      || fun->function_symbol ()->definition)
+	      || !fun->thunk.thunk_p)
 	  && symbol->real_symbol_p ())
 	{
 	  tree *val = map.get (symbol);
@@ -355,9 +376,16 @@ ipa_comdats (void)
 	      symbol->dump (dump_file);
 	      fprintf (dump_file, "To group: %s\n", IDENTIFIER_POINTER (group));
 	    }
-	  symbol->call_for_symbol_and_aliases (set_comdat_group,
-					     *comdat_head_map.get (group),
-					     true);
+	  if (is_a <cgraph_node *> (symbol))
+	   dyn_cast <cgraph_node *>(symbol)->call_for_symbol_and_aliases
+		  (set_comdat_group_1,
+		   *comdat_head_map.get (group),
+		   true);
+	  else
+	   symbol->call_for_symbol_and_aliases
+		  (set_comdat_group,
+		   *comdat_head_map.get (group),
+		   true);
 	}
     }
   return 0;