2005-11-16  Alexandre Oliva  <aoliva@redhat.com>
 
	* attribs.c (handle_weakref_attribute): New.
	(c_common_attribute_table): Add weakref.
	* defaults.h (ASM_OUTPUT_WEAKREF): Define.
	* doc/extend.texi: Document weakref attribute.
	* varasm.c (do_assemble_alias): Handle weakrefs.
	(finish_aliases_1): Do not reject weakrefs to external symbols.
	* gthr-posix.h: Define __gthrw.  For all identifiers that
	might be weak, introduce weakrefs or non-weak aliases with
	__gthrw, and prefix all uses with __ghtrw.
	* config/rs6000/rs6000.h (ASM_OUTPUT_WEAKREF): Define.
 
	* g++.old-deja/g++.ext/weakref1.C: New test.
	* g++.old-deja/g++.ext/weakref1a.cc: New helper file.
 
--- gcc/defaults.h.orig	2005-11-15 19:55:42.000000000 -0200
+++ gcc/defaults.h	2005-11-16 13:38:28.000000000 -0200
@@ -156,6 +156,25 @@
 #endif
 #endif
 
+/* This is how we tell the assembler that a symbol is a weak alias to
+   another symbol that doesn't require the other symbol to be defined.
+   Uses of the former will turn into weak uses of the latter, i.e.,
+   uses that, in case the latter is undefined, will not cause errors,
+   and will add it to the symbol table as weak undefined.  However, if
+   the latter is referenced directly, a strong reference prevails.  */
+#ifndef ASM_OUTPUT_WEAKREF
+#define ASM_OUTPUT_WEAKREF(FILE, DECL, NAME, VALUE)			\
+  do									\
+    {									\
+      fprintf ((FILE), "\t.weakref\t");					\
+      assemble_name ((FILE), (NAME));					\
+      fprintf ((FILE), ",");						\
+      assemble_name ((FILE), (VALUE));					\
+      fprintf ((FILE), "\n");						\
+    }									\
+  while (0)
+#endif
+
 /* This determines whether or not we support weak symbols.  */
 #ifndef SUPPORTS_WEAK
 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
--- gcc/doc/extend.texi.orig	2005-11-15 19:55:42.000000000 -0200
+++ gcc/doc/extend.texi	2005-11-15 19:55:48.000000000 -0200
@@ -2217,6 +2217,38 @@
 for ELF targets, and also for a.out targets when using the GNU assembler
 and linker.
 
+@item weakref
+@itemx weakref ("@var{target}")
+@cindex @code{weakref} attribute
+The @code{weakref} attribute marks a declaration as a weak reference.
+Without arguments, it should be accompanied by an @code{alias} attribute
+naming the target symbol.  Optionally, the @var{target} may be given as
+an argument to @code{weakref} itself.  In either case, @code{weakref}
+implicitly marks the declaration as @code{weak}.  Without a
+@var{target}, given as an argument to @code{weakref} or to @code{alias},
+@code{weakref} is equivalent to @code{weak}.
+
+@smallexample
+extern int x() __attribute__ ((weakref ("y")));
+/* is equivalent to... */
+extern int x() __attribute__ ((weak, weakref, alias ("y")));
+/* and to... */
+extern int x() __attribute__ ((weakref));
+extern int x() __attribute__ ((alias ("y")));
+@end smallexample
+
+A weak reference is an alias that does not by itself require a
+definition to be given for the target symbol.  If the target symbol is
+only referenced through weak references, then the becomes a @code{weak}
+undefined symbol.  If it is directly referenced, however, then such
+strong references prevail, and a definition will be required for the
+symbol, not necessarily in the same translation unit.
+
+The effect is equivalent to moving all references to the alias to a
+separate translation unit, renaming the alias to the aliased symbol,
+declaring it as weak, compiling the two separate translation units and
+performing a reloadable link on them.
+
 @item malloc
 @cindex @code{malloc} attribute
 The @code{malloc} attribute is used to tell the compiler that a function
--- gcc/gthr-posix.h.orig	2005-11-15 19:55:42.000000000 -0200
+++ gcc/gthr-posix.h	2005-11-15 19:55:48.000000000 -0200
@@ -43,6 +43,42 @@
 #define __GTHREAD_MUTEX_INIT PTHREAD_MUTEX_INITIALIZER
 #define __GTHREAD_ONCE_INIT PTHREAD_ONCE_INIT
 
+#if SUPPORTS_WEAK && GTHREAD_USE_WEAK && defined __GNUC_RH_RELEASE__ && __GNUC__ == 3 && __GNUC_MINOR__ == 2 && __GNUC_PATCHLEVEL__ == 3 && __GNUC_RH_RELEASE__ > 53 && !defined __attribute__
+# define __gthrw(name) \
+  extern __typeof(name) __gthrw_ ## name __attribute__ ((__weakref__(#name)))
+
+__gthrw(pthread_once);
+__gthrw(pthread_key_create);
+__gthrw(pthread_key_delete);
+__gthrw(pthread_getspecific);
+__gthrw(pthread_setspecific);
+__gthrw(pthread_create);
+
+__gthrw(pthread_mutex_lock );
+__gthrw(pthread_mutex_trylock );
+__gthrw(pthread_mutex_unlock );
+
+#ifdef _LIBOBJC
+/* Objective C.  */
+__gthrw(pthread_cond_broadcast);
+__gthrw(pthread_cond_destroy);
+__gthrw(pthread_cond_init);
+__gthrw(pthread_cond_signal);
+__gthrw(pthread_cond_wait);
+__gthrw(pthread_exit);
+__gthrw(pthread_mutex_init);
+__gthrw(pthread_mutex_destroy);
+__gthrw(pthread_self);
+__gthrw(sched_get_priority_max);
+__gthrw(sched_get_priority_min);
+__gthrw(sched_yield);
+__gthrw(pthread_attr_destroy);
+__gthrw(pthread_attr_init);
+__gthrw(pthread_attr_setdetachstate);
+__gthrw(pthread_getschedparam);
+__gthrw(pthread_setschedparam);
+#endif
+#else
 #if SUPPORTS_WEAK && GTHREAD_USE_WEAK
 
 #pragma weak pthread_once
@@ -76,11 +112,47 @@
 #pragma weak pthread_getschedparam
 #pragma weak pthread_setschedparam
 #endif
+#endif
+
+#define __gthrw_pthread_once pthread_once
+#define __gthrw_pthread_key_create pthread_key_create
+#define __gthrw_pthread_key_delete pthread_key_delete
+#define __gthrw_pthread_getspecific pthread_getspecific
+#define __gthrw_pthread_setspecific pthread_setspecific
+#define __gthrw_pthread_create pthread_create
+
+#define __gthrw_pthread_mutex_lock  pthread_mutex_lock
+#define __gthrw_pthread_mutex_trylock  pthread_mutex_trylock
+#define __gthrw_pthread_mutex_unlock  pthread_mutex_unlock
+
+#ifdef _LIBOBJC
+/* Objective C.  */
+#define __gthrw_pthread_cond_broadcast pthread_cond_broadcast
+#define __gthrw_pthread_cond_destroy pthread_cond_destroy
+#define __gthrw_pthread_cond_init pthread_cond_init
+#define __gthrw_pthread_cond_signal pthread_cond_signal
+#define __gthrw_pthread_cond_wait pthread_cond_wait
+#define __gthrw_pthread_exit pthread_exit
+#define __gthrw_pthread_mutex_init pthread_mutex_init
+#define __gthrw_pthread_mutex_destroy pthread_mutex_destroy
+#define __gthrw_pthread_self pthread_self
+#define __gthrw_sched_get_priority_max sched_get_priority_max
+#define __gthrw_sched_get_priority_min sched_get_priority_min
+#define __gthrw_sched_yield sched_yield
+#define __gthrw_pthread_attr_destroy pthread_attr_destroy
+#define __gthrw_pthread_attr_init pthread_attr_init
+#define __gthrw_pthread_attr_setdetachstate pthread_attr_setdetachstate
+#define __gthrw_pthread_getschedparam pthread_getschedparam
+#define __gthrw_pthread_setschedparam pthread_setschedparam
+#endif
+#endif
+
+#if SUPPORTS_WEAK && GTHREAD_USE_WEAK
 
 static inline int
 __gthread_active_p (void)
 {
-  static void *const __gthread_active_ptr = (void *) &pthread_create;
+  static void *const __gthread_active_ptr = (void *) &__gthrw_pthread_create;
   return __gthread_active_ptr != 0;
 }
 
@@ -119,13 +191,13 @@
   if (__gthread_active_p ())
     {
       /* Initialize the thread storage key */
-      if (pthread_key_create(&_objc_thread_storage, NULL) == 0)
+      if (__gthrw_pthread_key_create(&_objc_thread_storage, NULL) == 0)
         {
           /* The normal default detach state for threads is
            * PTHREAD_CREATE_JOINABLE which causes threads to not die
            * when you think they should.  */
-          if (pthread_attr_init(&_objc_thread_attribs) == 0
-              && pthread_attr_setdetachstate(&_objc_thread_attribs, 
+          if (__gthrw_pthread_attr_init(&_objc_thread_attribs) == 0
+              && __gthrw_pthread_attr_setdetachstate(&_objc_thread_attribs,
                                              PTHREAD_CREATE_DETACHED) == 0)
             return 0;
         }
@@ -139,8 +211,8 @@
 __gthread_objc_close_thread_system(void)
 {
   if (__gthread_active_p ()
-      && pthread_key_delete(_objc_thread_storage) == 0
-      && pthread_attr_destroy(&_objc_thread_attribs) == 0)
+      && __gthrw_pthread_key_delete(_objc_thread_storage) == 0
+      && __gthrw_pthread_attr_destroy(&_objc_thread_attribs) == 0)
     return 0;
 
   return -1;
@@ -158,7 +230,7 @@
   if (!__gthread_active_p ())
     return NULL;
  
-  if ( !(pthread_create(&new_thread_handle, NULL, (void *)func, arg)) )
+  if ( !(__gthrw_pthread_create(&new_thread_handle, NULL, (void *)func, arg)) )
     thread_id = (objc_thread_t) new_thread_handle;
   else
     thread_id = NULL;
@@ -173,17 +245,17 @@
   if (!__gthread_active_p())
     return -1;
   else {
-    pthread_t thread_id = pthread_self();
+    pthread_t thread_id = __gthrw_pthread_self();
     int policy;
     struct sched_param params;
     int priority_min, priority_max;
 
-    if (pthread_getschedparam(thread_id, &policy, &params) == 0)
+    if (__gthrw_pthread_getschedparam(thread_id, &policy, &params) == 0)
       {
-        if ((priority_max = sched_get_priority_max(policy)) != 0)
+        if ((priority_max = __gthrw_sched_get_priority_max(policy)) != 0)
           return -1;
 
-        if ((priority_min = sched_get_priority_min(policy)) != 0)
+        if ((priority_min = __gthrw_sched_get_priority_min(policy)) != 0)
           return -1;
 
         if (priority > priority_max)
@@ -197,7 +269,7 @@
          * this should be a pointer to policy but pthread.h is universally
          * at odds with this.
          */
-        if (pthread_setschedparam(thread_id, policy, &params) == 0)
+        if (__gthrw_pthread_setschedparam(thread_id, policy, &params) == 0)
           return 0;
       }
     return -1;
@@ -213,7 +285,7 @@
       int policy;
       struct sched_param params;
 
-      if (pthread_getschedparam(pthread_self(), &policy, &params) == 0)
+      if (__gthrw_pthread_getschedparam(__gthrw_pthread_self(), &policy, &params) == 0)
         return params.sched_priority;
       else
         return -1;
@@ -227,7 +299,7 @@
 __gthread_objc_thread_yield(void)
 {
   if (__gthread_active_p ())
-    sched_yield();
+    __gthrw_sched_yield();
 }
 
 /* Terminate the current thread.  */
@@ -236,7 +308,7 @@
 {
   if (__gthread_active_p ())
     /* exit the thread */
-    pthread_exit(&__objc_thread_exit_status);
+    __gthrw_pthread_exit(&__objc_thread_exit_status);
 
   /* Failed if we reached here */
   return -1;
@@ -247,7 +319,7 @@
 __gthread_objc_thread_id(void)
 {
   if (__gthread_active_p ())
-    return (objc_thread_t) pthread_self();
+    return (objc_thread_t) __gthrw_pthread_self();
   else
     return (objc_thread_t) 1;
 }
@@ -257,7 +329,7 @@
 __gthread_objc_thread_set_data(void *value)
 {
   if (__gthread_active_p ())
-    return pthread_setspecific(_objc_thread_storage, value);
+    return __gthrw_pthread_setspecific(_objc_thread_storage, value);
   else
     {
       thread_local_storage = value;
@@ -270,7 +342,7 @@
 __gthread_objc_thread_get_data(void)
 {
   if (__gthread_active_p ())
-    return pthread_getspecific(_objc_thread_storage);
+    return __gthrw_pthread_getspecific(_objc_thread_storage);
   else
     return thread_local_storage;
 }
@@ -285,7 +357,7 @@
     {
       mutex->backend = objc_malloc(sizeof(pthread_mutex_t));
 
-      if (pthread_mutex_init((pthread_mutex_t *)mutex->backend, NULL))
+      if (__gthrw_pthread_mutex_init((pthread_mutex_t *)mutex->backend, NULL))
 	{
 	  objc_free(mutex->backend);
 	  mutex->backend = NULL;
@@ -306,18 +378,18 @@
 
       /*
        * Posix Threads specifically require that the thread be unlocked
-       * for pthread_mutex_destroy to work.
+       * for __gthrw_pthread_mutex_destroy to work.
        */
 
       do
 	{
-	  count = pthread_mutex_unlock((pthread_mutex_t *)mutex->backend);
+	  count = __gthrw_pthread_mutex_unlock((pthread_mutex_t *)mutex->backend);
 	  if (count < 0)
 	    return -1;
 	}
       while (count);
 
-      if (pthread_mutex_destroy((pthread_mutex_t *)mutex->backend))
+      if (__gthrw_pthread_mutex_destroy((pthread_mutex_t *)mutex->backend))
 	return -1;
 
       objc_free(mutex->backend);
@@ -331,7 +403,7 @@
 __gthread_objc_mutex_lock(objc_mutex_t mutex)
 {
   if (__gthread_active_p () 
-      && pthread_mutex_lock((pthread_mutex_t *)mutex->backend) != 0)
+      && __gthrw_pthread_mutex_lock((pthread_mutex_t *)mutex->backend) != 0)
     {
       return -1;
     }
@@ -344,7 +416,7 @@
 __gthread_objc_mutex_trylock(objc_mutex_t mutex)
 {
   if (__gthread_active_p () 
-      && pthread_mutex_trylock((pthread_mutex_t *)mutex->backend) != 0)
+      && __gthrw_pthread_mutex_trylock((pthread_mutex_t *)mutex->backend) != 0)
     {
       return -1;
     }
@@ -357,7 +429,7 @@
 __gthread_objc_mutex_unlock(objc_mutex_t mutex)
 {
   if (__gthread_active_p () 
-      && pthread_mutex_unlock((pthread_mutex_t *)mutex->backend) != 0)
+      && __gthrw_pthread_mutex_unlock((pthread_mutex_t *)mutex->backend) != 0)
     {
       return -1;
     }
@@ -375,7 +447,7 @@
     {
       condition->backend = objc_malloc(sizeof(pthread_cond_t));
 
-      if (pthread_cond_init((pthread_cond_t *)condition->backend, NULL))
+      if (__gthrw_pthread_cond_init((pthread_cond_t *)condition->backend, NULL))
 	{
 	  objc_free(condition->backend);
 	  condition->backend = NULL;
@@ -392,7 +464,7 @@
 {
   if (__gthread_active_p ())
     {
-      if (pthread_cond_destroy((pthread_cond_t *)condition->backend))
+      if (__gthrw_pthread_cond_destroy((pthread_cond_t *)condition->backend))
 	return -1;
 
       objc_free(condition->backend);
@@ -406,7 +478,7 @@
 __gthread_objc_condition_wait(objc_condition_t condition, objc_mutex_t mutex)
 {
   if (__gthread_active_p ())
-    return pthread_cond_wait((pthread_cond_t *)condition->backend,
+    return __gthrw_pthread_cond_wait((pthread_cond_t *)condition->backend,
 			   (pthread_mutex_t *)mutex->backend);
   else
     return 0;
@@ -417,7 +489,7 @@
 __gthread_objc_condition_broadcast(objc_condition_t condition)
 {
   if (__gthread_active_p ())
-    return pthread_cond_broadcast((pthread_cond_t *)condition->backend);
+    return __gthrw_pthread_cond_broadcast((pthread_cond_t *)condition->backend);
   else
     return 0;
 }
@@ -427,7 +499,7 @@
 __gthread_objc_condition_signal(objc_condition_t condition)
 {
   if (__gthread_active_p ())
-    return pthread_cond_signal((pthread_cond_t *)condition->backend);
+    return __gthrw_pthread_cond_signal((pthread_cond_t *)condition->backend);
   else
     return 0;
 }
@@ -438,7 +510,7 @@
 __gthread_once (__gthread_once_t *once, void (*func) (void))
 {
   if (__gthread_active_p ())
-    return pthread_once (once, func);
+    return __gthrw_pthread_once (once, func);
   else
     return -1;
 }
@@ -446,7 +518,7 @@
 static inline int
 __gthread_key_create (__gthread_key_t *key, void (*dtor) (void *))
 {
-  return pthread_key_create (key, dtor);
+  return __gthrw_pthread_key_create (key, dtor);
 }
 
 static inline int
@@ -454,7 +526,7 @@
 {
   /* Just reset the key value to zero.  */
   if (ptr)
-    return pthread_setspecific (key, 0);
+    return __gthrw_pthread_setspecific (key, 0);
   else
     return 0;
 }
@@ -462,26 +534,26 @@
 static inline int
 __gthread_key_delete (__gthread_key_t key)
 {
-  return pthread_key_delete (key);
+  return __gthrw_pthread_key_delete (key);
 }
 
 static inline void *
 __gthread_getspecific (__gthread_key_t key)
 {
-  return pthread_getspecific (key);
+  return __gthrw_pthread_getspecific (key);
 }
 
 static inline int
 __gthread_setspecific (__gthread_key_t key, const void *ptr)
 {
-  return pthread_setspecific (key, ptr);
+  return __gthrw_pthread_setspecific (key, ptr);
 }
 
 static inline int
 __gthread_mutex_lock (__gthread_mutex_t *mutex)
 {
   if (__gthread_active_p ())
-    return pthread_mutex_lock (mutex);
+    return __gthrw_pthread_mutex_lock (mutex);
   else
     return 0;
 }
@@ -490,7 +562,7 @@
 __gthread_mutex_trylock (__gthread_mutex_t *mutex)
 {
   if (__gthread_active_p ())
-    return pthread_mutex_trylock (mutex);
+    return __gthrw_pthread_mutex_trylock (mutex);
   else
     return 0;
 }
@@ -499,7 +571,7 @@
 __gthread_mutex_unlock (__gthread_mutex_t *mutex)
 {
   if (__gthread_active_p ())
-    return pthread_mutex_unlock (mutex);
+    return __gthrw_pthread_mutex_unlock (mutex);
   else
     return 0;
 }
--- gcc/varasm.c.orig	2005-11-15 19:55:42.000000000 -0200
+++ gcc/varasm.c	2005-11-16 13:38:44.000000000 -0200
@@ -5130,6 +5130,9 @@
       if (! TREE_USED (decl))
 	continue;
 
+      if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
+	continue;
+
 #ifdef ASM_WEAKEN_DECL
       ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
 #else
@@ -5195,6 +5198,18 @@
 
   name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
 
+  if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
+    {
+#ifdef ASM_OUTPUT_WEAKREF
+      ASM_OUTPUT_WEAKREF (asm_out_file, decl,
+			  IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
+			  IDENTIFIER_POINTER (target));
+#else
+      error ("%Jweakref is not supported in this configuration", decl);
+#endif
+      return;
+    }
+
 #ifdef ASM_OUTPUT_DEF
   /* Make name accessible from other files, if appropriate.  */
   if (TREE_PUBLIC (decl))
--- gcc/attribs.c.orig	2005-11-15 19:55:42.000000000 -0200
+++ gcc/attribs.c	2005-11-15 19:55:48.000000000 -0200
@@ -75,6 +75,8 @@
 						 bool *));
 static tree handle_alias_attribute	PARAMS ((tree *, tree, tree, int,
 						 bool *));
+static tree handle_weakref_attribute	PARAMS ((tree *, tree, tree, int,
+						 bool *));
 static tree handle_visibility_attribute	PARAMS ((tree *, tree, tree, int,
 						 bool *));
 static tree handle_tls_model_attribute	PARAMS ((tree *, tree, tree, int,
@@ -140,6 +142,8 @@
 			      handle_weak_attribute },
   { "alias",                  1, 1, true,  false, false,
 			      handle_alias_attribute },
+  { "weakref",                0, 1, true,  false, false,
+			      handle_weakref_attribute },
   { "no_instrument_function", 0, 0, true,  false, false,
 			      handle_no_instrument_function_attribute },
   { "malloc",                 0, 0, true,  false, false,
@@ -1060,7 +1064,12 @@
       if (TREE_CODE (decl) == FUNCTION_DECL)
 	DECL_INITIAL (decl) = error_mark_node;
       else
-	DECL_EXTERNAL (decl) = 0;
+	{
+	  if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
+	    DECL_EXTERNAL (decl) = 1;
+	  else
+	    DECL_EXTERNAL (decl) = 0;
+	}
     }
   else
     {
@@ -1071,6 +1080,44 @@
   return NULL_TREE;
 }
 
+/* Handle a "weakref" attribute; arguments as in struct
+   attribute_spec.handler.  */
+
+static tree
+handle_weakref_attribute (node, name, args, flags, no_add_attrs)
+     tree *node;
+     tree name ATTRIBUTE_UNUSED;
+     tree args;
+     int flags;
+     bool *no_add_attrs;
+{
+  tree attr = NULL_TREE;
+
+  /* The idea here is that `weakref("name")' mutates into `weakref,
+     alias("name")', and weakref without arguments, in turn,
+     implicitly adds weak. */
+
+  if (args)
+    {
+      attr = tree_cons (get_identifier ("alias"), args, attr);
+      attr = tree_cons (get_identifier ("weakref"), NULL_TREE, attr);
+
+      *no_add_attrs = true;
+    }
+  else
+    {
+      if (lookup_attribute ("alias", DECL_ATTRIBUTES (*node)))
+	error ("%Jweakref attribute must appear before alias attribute",
+	       *node);
+
+      attr = tree_cons (get_identifier ("weak"), NULL_TREE, attr);
+    }
+
+  decl_attributes (node, attr, flags);
+
+  return NULL_TREE;
+}
+
 /* Handle an "visibility" attribute; arguments as in
    struct attribute_spec.handler.  */
 
--- gcc/testsuite/g++.old-deja/g++.ext/weakref1.C	1970-01-01 00:00:00.000000000 +0000
+++ gcc/testsuite/g++.old-deja/g++.ext/weakref1.C	2005-11-15 19:55:48.000000000 -0200
@@ -0,0 +1,226 @@
+// execution test
+// Additional sources: weakref1a.cc
+
+// Copyright 2005 Free Software Foundation, Inc.
+// Contributed by Alexandre Oliva <aoliva@redhat.com>
+
+// Torture test for weakrefs.  The first letter of an identifier
+// indicates whether/how it is defined; the second letter indicates
+// whether it is part of a variable or function test; the number that
+// follows is a test counter, and a letter that may follow enables
+// multiple identifiers within the same test (e.g., multiple weakrefs
+// or pointers to the same identifier).
+
+// Identifiers starting with W are weakrefs; those with p are
+// pointers; those with g are global definitions; those with l are
+// local definitions; those with w are expected to be weak undefined
+// in the symbol table; those with u are expected to be marked as
+// non-weak undefined in the symbol table.
+
+#include <stdlib.h>
+
+#define USED __attribute__((used))
+
+extern "C" {
+typedef int vtype;
+
+extern vtype wv1;
+extern vtype Wv1a __attribute__((weakref ("wv1")));
+static vtype *pv1a USED = &Wv1a;
+extern vtype Wv1b __attribute__((weak, weakref, alias ("wv1")));
+static vtype *pv1b USED = &Wv1b;
+extern vtype Wv1c __attribute__((weakref));
+extern vtype Wv1c __attribute__((alias ("wv1")));
+static vtype *pv1c USED = &Wv1c;
+
+vtype gv2;
+extern vtype Wv2a __attribute__((weakref ("gv2")));
+static vtype *pv2a USED = &Wv2a;
+
+static vtype lv3;
+extern vtype Wv3a __attribute__((weakref ("lv3")));
+static vtype *pv3a USED = &Wv3a;
+
+extern vtype uv4;
+extern vtype Wv4a __attribute__((weakref ("uv4")));
+static vtype *pv4a USED = &Wv4a;
+static vtype *pv4 USED = &uv4;
+
+extern vtype Wv5a __attribute__((weakref ("uv5")));
+static vtype *pv5a USED = &Wv5a;
+extern vtype uv5;
+static vtype *pv5 USED = &uv5;
+
+extern vtype Wv6a __attribute__((weakref ("wv6")));
+static vtype *pv6a USED = &Wv6a;
+extern vtype wv6;
+
+extern vtype Wv7a __attribute__((weakref ("uv7")));
+static vtype* USED fv7 (void) {
+  return &Wv7a;
+}
+extern vtype uv7;
+static vtype* USED fv7a (void) {
+  return &uv7;
+}
+
+extern vtype uv8;
+static vtype* USED fv8a (void) {
+  return &uv8;
+}
+extern vtype Wv8a __attribute__((weakref ("uv8")));
+static vtype* USED fv8 (void) {
+  return &Wv8a;
+}
+
+extern vtype wv9 __attribute__((weak));
+extern vtype Wv9a __attribute__((weakref ("wv9")));
+static vtype *pv9a USED = &Wv9a;
+
+extern vtype Wv10a __attribute__((weakref ("Wv10b")));
+extern vtype Wv10b __attribute__((weakref ("Wv10c")));
+extern vtype Wv10c __attribute__((weakref ("Wv10d")));
+extern vtype Wv10d __attribute__((weakref ("wv10")));
+extern vtype wv10;
+
+extern vtype wv11;
+extern vtype Wv11d __attribute__((weakref ("wv11")));
+extern vtype Wv11c __attribute__((weakref ("Wv11d")));
+extern vtype Wv11b __attribute__((weakref ("Wv11c")));
+extern vtype Wv11a __attribute__((weakref ("Wv11b")));
+
+extern vtype Wv12 __attribute__((weakref ("wv12")));
+extern vtype wv12 __attribute__((weak));
+
+extern vtype Wv13 __attribute__((weakref ("wv13")));
+extern vtype wv13 __attribute__((weak));
+
+extern vtype Wv14a __attribute__((weakref ("wv14")));
+extern vtype Wv14b __attribute__((weakref ("wv14")));
+extern vtype wv14 __attribute__((weak));
+
+typedef void ftype(void);
+
+extern ftype wf1;
+extern ftype Wf1a __attribute__((weakref ("wf1")));
+static ftype *pf1a USED = &Wf1a;
+extern ftype Wf1b __attribute__((weak, weakref, alias ("wf1")));
+static ftype *pf1b USED = &Wf1b;
+extern ftype Wf1c __attribute__((weakref));
+extern ftype Wf1c __attribute__((alias ("wf1")));
+static ftype *pf1c USED = &Wf1c;
+
+void gf2(void) {}
+extern ftype Wf2a __attribute__((weakref ("gf2")));
+static ftype *pf2a USED = &Wf2a;
+
+static void lf3(void) {}
+extern ftype Wf3a __attribute__((weakref ("lf3")));
+static ftype *pf3a USED = &Wf3a;
+
+extern ftype uf4;
+extern ftype Wf4a __attribute__((weakref ("uf4")));
+static ftype *pf4a USED = &Wf4a;
+static ftype *pf4 USED = &uf4;
+
+extern ftype Wf5a __attribute__((weakref ("uf5")));
+static ftype *pf5a USED = &Wf5a;
+extern ftype uf5;
+static ftype *pf5 USED = &uf5;
+
+extern ftype Wf6a __attribute__((weakref ("wf6")));
+static ftype *pf6a USED = &Wf6a;
+extern ftype wf6;
+
+extern ftype Wf7a __attribute__((weakref ("uf7")));
+static ftype* USED ff7 (void) {
+  return &Wf7a;
+}
+extern ftype uf7;
+static ftype* USED ff7a (void) {
+  return &uf7;
+}
+
+extern ftype uf8;
+static ftype* USED ff8a (void) {
+  return &uf8;
+}
+extern ftype Wf8a __attribute__((weakref ("uf8")));
+static ftype* USED ff8 (void) {
+  return &Wf8a;
+}
+
+extern ftype wf9 __attribute__((weak));
+extern ftype Wf9a __attribute__((weakref ("wf9")));
+static ftype *pf9a USED = &Wf9a;
+
+extern ftype Wf10a __attribute__((weakref ("Wf10b")));
+extern ftype Wf10b __attribute__((weakref ("Wf10c")));
+extern ftype Wf10c __attribute__((weakref ("Wf10d")));
+extern ftype Wf10d __attribute__((weakref ("wf10")));
+extern ftype wf10;
+
+extern ftype wf11;
+extern ftype Wf11d __attribute__((weakref ("wf11")));
+extern ftype Wf11c __attribute__((weakref ("Wf11d")));
+extern ftype Wf11b __attribute__((weakref ("Wf11c")));
+extern ftype Wf11a __attribute__((weakref ("Wf11b")));
+
+extern ftype Wf12 __attribute__((weakref ("wf12")));
+extern ftype wf12 __attribute__((weak));
+
+extern ftype Wf13 __attribute__((weakref ("wf13")));
+extern ftype wf13 __attribute__((weak));
+
+extern ftype Wf14a __attribute__((weakref ("wf14")));
+extern ftype Wf14b __attribute__((weakref ("wf14")));
+extern ftype wf14 __attribute__((weak));
+}
+
+#define chk(p) do { if (!p) abort (); } while (0)
+
+int main () {
+  chk (!pv1a);
+  chk (!pv1b);
+  chk (!pv1c);
+  chk (pv2a);
+  chk (pv3a);
+  chk (pv4a);
+  chk (pv4);
+  chk (pv5a);
+  chk (pv5);
+  chk (!pv6a);
+  chk (fv7 ());
+  chk (fv7a ());
+  chk (fv8 ());
+  chk (fv8a ());
+  chk (!pv9a);
+  chk (!&Wv10a);
+  chk (!&Wv11a);
+  chk (!&Wv12);
+  chk (!&wv12);
+  chk (!&wv13);
+  chk (!&Wv14a);
+
+  chk (!pf1a);
+  chk (!pf1b);
+  chk (!pf1c);
+  chk (pf2a);
+  chk (pf3a);
+  chk (pf4a);
+  chk (pf4);
+  chk (pf5a);
+  chk (pf5);
+  chk (!pf6a);
+  chk (ff7 ());
+  chk (ff7a ());
+  chk (ff8 ());
+  chk (ff8a ());
+  chk (!pf9a);
+  chk (!&Wf10a);
+  chk (!&Wf11a);
+  chk (!&Wf12);
+  chk (!&wf12);
+  chk (!&wf13);
+  chk (!&Wf14a);
+}
--- gcc/testsuite/g++.old-deja/g++.ext/weakref1a.cc	1970-01-01 00:00:00.000000000 +0000
+++ gcc/testsuite/g++.old-deja/g++.ext/weakref1a.cc	2005-11-15 19:55:48.000000000 -0200
@@ -0,0 +1,10 @@
+extern "C" {
+int uv4;
+int uv5;
+int uv7;
+int uv8;
+void uf4 (void) {}
+void uf5 (void) {}
+void uf7 (void) {}
+void uf8 (void) {}
+}
--- gcc/config/rs6000/rs6000.h.orig	2005-11-16 13:37:46.000000000 -0200
+++ gcc/config/rs6000/rs6000.h	2005-11-16 14:10:01.000000000 -0200
@@ -2487,6 +2487,24 @@
   while (0)
 #endif
 
+#define ASM_OUTPUT_WEAKREF(FILE, DECL, NAME, VALUE)			\
+  do									\
+    {									\
+      fputs ("\t.weakref\t", (FILE));					\
+      RS6000_OUTPUT_BASENAME ((FILE), (NAME)); 				\
+      fputs (", ", (FILE));						\
+      RS6000_OUTPUT_BASENAME ((FILE), (VALUE));				\
+      if ((DECL) && TREE_CODE (DECL) == FUNCTION_DECL			\
+	  && DEFAULT_ABI == ABI_AIX)					\
+	{								\
+	  fputs ("\n\t.weakref\t.", (FILE));				\
+	  RS6000_OUTPUT_BASENAME ((FILE), (NAME)); 			\
+	  fputs (", .", (FILE));					\
+	  RS6000_OUTPUT_BASENAME ((FILE), (VALUE));			\
+	}								\
+      fputc ('\n', (FILE));						\
+    } while (0)
+
 /* This implements the `alias' attribute.  */
 #undef	ASM_OUTPUT_DEF_FROM_DECLS
 #define	ASM_OUTPUT_DEF_FROM_DECLS(FILE, DECL, TARGET)			\