re PR c++/47202 (Endless recursion during mangling)

	PR c++/47202
gcc/cp/
	* decl.c (cxx_comdat_group): Return a decl.
	* optimize.c (cdtor_comdat_group): Get its DECL_ASSEMBLER_NAME.
gcc/
	* cgraph.h (symtab_node::get_comdat_group_id): New.
	* cgraphunit.c (analyze_functions): Call it.
	* symtab.c (dump_symtab_node): Likewise.
	* tree.c (decl_comdat_group_id): New.
	* tree.h: Declare it.
	* lto-streamer-out.c (write_symbol): Use it.
	* trans-mem.c (ipa_tm_create_version_alias): Likewise.

From-SVN: r211026

gcc/ChangeLog

+2014-05-28  Jason Merrill  <jason@redhat.com>
+
+	PR c++/47202
+	* cgraph.h (symtab_node::get_comdat_group_id): New.
+	* cgraphunit.c (analyze_functions): Call it.
+	* symtab.c (dump_symtab_node): Likewise.
+	* tree.c (decl_comdat_group_id): New.
+	* tree.h: Declare it.
+	* lto-streamer-out.c (write_symbol): Use it.
+	* trans-mem.c (ipa_tm_create_version_alias): Likewise.
+
 2014-05-28  Francois-Xavier Coudert  <fxcoudert@gcc.gnu.org>
 
 	PR bootstrap/PR61146

gcc/cgraph.h

@@ -147,6 +147,13 @@ public:
       return comdat_group_;
     }
 
+  tree get_comdat_group_id ()
+    {
+      if (comdat_group_ && TREE_CODE (comdat_group_) != IDENTIFIER_NODE)
+	comdat_group_ = DECL_ASSEMBLER_NAME (comdat_group_);
+      return comdat_group_;
+    }
+
   /* Set comdat group.  */
   void set_comdat_group (tree group)
     {

gcc/cgraphunit.c

@@ -974,6 +974,8 @@ analyze_functions (void)
 	   node != first_analyzed
 	   && node != first_analyzed_var; node = node->next)
 	{
+	  /* Convert COMDAT group designators to IDENTIFIER_NODEs.  */
+	  node->get_comdat_group_id ();
 	  if (decide_is_symbol_needed (node))
 	    {
 	      enqueue_node (node);

gcc/cp/ChangeLog

 2014-05-28  Jason Merrill  <jason@redhat.com>
 
+	PR c++/47202
+	* decl.c (cxx_comdat_group): Return a decl.
+	* optimize.c (cdtor_comdat_group): Get its DECL_ASSEMBLER_NAME.
+
 	* pt.c (tsubst) [ARRAY_TYPE]: Check for array of array of unknown
 	bound.
 

gcc/cp/decl.c

@@ -14484,18 +14484,17 @@ cp_missing_noreturn_ok_p (tree decl)
   return DECL_MAIN_P (decl);
 }
 
-/* Return the COMDAT group into which DECL should be placed.  */
+/* Return the decl used to identify the COMDAT group into which DECL should
+   be placed.  */
 
 tree
 cxx_comdat_group (tree decl)
 {
-  tree name;
-
   /* Virtual tables, construction virtual tables, and virtual table
      tables all go in a single COMDAT group, named after the primary
      virtual table.  */
   if (VAR_P (decl) && DECL_VTABLE_OR_VTT_P (decl))
-    name = DECL_ASSEMBLER_NAME (CLASSTYPE_VTABLES (DECL_CONTEXT (decl)));
+    decl = CLASSTYPE_VTABLES (DECL_CONTEXT (decl));
   /* For all other DECLs, the COMDAT group is the mangled name of the
      declaration itself.  */
   else
@@ -14513,10 +14512,9 @@ cxx_comdat_group (tree decl)
 	  else
 	    break;
 	}
-      name = DECL_ASSEMBLER_NAME (decl);
     }
 
-  return name;
+  return decl;
 }
 
 /* Returns the return type for FN as written by the user, which may include

gcc/cp/mangle.c

@@ -3520,7 +3520,11 @@ mangle_decl (const tree decl)
       if (vague_linkage_p (decl))
 	DECL_WEAK (alias) = 1;
       if (TREE_CODE (decl) == FUNCTION_DECL)
-	cgraph_same_body_alias (cgraph_get_create_node (decl), alias, decl);
+	{
+	  /* Don't create an alias to an unreferenced function.  */
+	  if (struct cgraph_node *n = cgraph_get_node (decl))
+	    cgraph_same_body_alias (n, alias, decl);
+	}
       else
 	varpool_extra_name_alias (alias, decl);
 #endif

gcc/cp/optimize.c

@@ -170,6 +170,8 @@ cdtor_comdat_group (tree complete, tree base)
     complete_name = cxx_comdat_group (complete);
   if (base_name == NULL)
     base_name = cxx_comdat_group (base);
+  complete_name = DECL_ASSEMBLER_NAME (complete_name);
+  base_name = DECL_ASSEMBLER_NAME (base_name);
   gcc_assert (IDENTIFIER_LENGTH (complete_name)
 	      == IDENTIFIER_LENGTH (base_name));
   grp_name = XALLOCAVEC (char, IDENTIFIER_LENGTH (complete_name) + 1);

gcc/lto-streamer-out.c

@@ -2329,7 +2329,7 @@ write_symbol (struct streamer_tree_cache_d *cache,
     size = 0;
 
   if (DECL_ONE_ONLY (t))
-    comdat = IDENTIFIER_POINTER (DECL_COMDAT_GROUP (t));
+    comdat = IDENTIFIER_POINTER (decl_comdat_group_id (t));
   else
     comdat = "";
 

gcc/symtab.c

@@ -560,7 +560,7 @@ dump_symtab_base (FILE *f, symtab_node *node)
     fprintf (f, " comdat");
   if (node->get_comdat_group ())
     fprintf (f, " comdat_group:%s",
-	     IDENTIFIER_POINTER (node->get_comdat_group ()));
+	     IDENTIFIER_POINTER (node->get_comdat_group_id ()));
   if (DECL_ONE_ONLY (node->decl))
     fprintf (f, " one_only");
   if (DECL_SECTION_NAME (node->decl))
@@ -1062,7 +1062,7 @@ symtab_resolve_alias (symtab_node *node, symtab_node *target)
   node->analyzed = true;
   ipa_record_reference (node, target, IPA_REF_ALIAS, NULL);
 
-  /* Alias targets become reudndant after alias is resolved into an reference.
+  /* Alias targets become redundant after alias is resolved into an reference.
      We do not want to keep it around or we would have to mind updating them
      when renaming symbols.  */
   node->alias_target = NULL;

gcc/trans-mem.c

@@ -4852,7 +4852,7 @@ ipa_tm_create_version_alias (struct cgraph_node *node, void *data)
 
   /* Perform the same remapping to the comdat group.  */
   if (DECL_ONE_ONLY (new_decl))
-    varpool_get_node (new_decl)->set_comdat_group (tm_mangle (DECL_COMDAT_GROUP (old_decl)));
+    varpool_get_node (new_decl)->set_comdat_group (tm_mangle (decl_comdat_group_id (old_decl)));
 
   new_node = cgraph_same_body_alias (NULL, new_decl, info->new_decl);
   new_node->tm_clone = true;

gcc/tree.c

@@ -603,7 +603,9 @@ decl_assembler_name (tree decl)
   return DECL_WITH_VIS_CHECK (decl)->decl_with_vis.assembler_name;
 }
 
-/* Return comdat group of DECL.  */
+/* When the target supports COMDAT groups, this indicates which group the
+   DECL is associated with.  This can be either an IDENTIFIER_NODE or a
+   decl, in which case its DECL_ASSEMBLER_NAME identifies the group.  */
 tree
 decl_comdat_group (tree node)
 {
@@ -613,6 +615,16 @@ decl_comdat_group (tree node)
   return snode->get_comdat_group ();
 }
 
+/* Likewise, but make sure it's been reduced to an IDENTIFIER_NODE.  */
+tree
+decl_comdat_group_id (tree node)
+{
+  struct symtab_node *snode = symtab_get_node (node);
+  if (!snode)
+    return NULL;
+  return snode->get_comdat_group_id ();
+}
+
 /* Compute the number of bytes occupied by a tree with code CODE.
    This function cannot be used for nodes that have variable sizes,
    including TREE_VEC, INTEGER_CST, STRING_CST, and CALL_EXPR.  */

gcc/tree.h

@@ -3432,6 +3432,7 @@ tree_operand_check_code (const_tree __t, enum tree_code __code, int __i,
 
 extern tree decl_assembler_name (tree);
 extern tree decl_comdat_group (tree);
+extern tree decl_comdat_group_id (tree);
 
 /* Compute the number of bytes occupied by 'node'.  This routine only
    looks at TREE_CODE and, if the code is TREE_VEC, TREE_VEC_LENGTH.  */