Index: gcc/ChangeLog

2005-12-05  Geoffrey Keating  <geoffk@apple.com>

	* varasm.c (default_binds_local_p_1): Weakrefs don't bind locally.
	A hidden weak object does bind locally.  Strong linkonce data
	counts like any other strong symbol for binding.
	(weak_finish_1): Don't specially handle weakrefs, they no longer
	arrive here.
	(assemble_alias): Weakrefs can't be TREE_PUBLIC yet.
	* c-common.c (handle_alias_attribute): Allow static aliases
	of variables.
	(handle_weakref_attribute): Don't call declare_weak on weakrefs.
	* gthr-dce.h: Make weakrefs static.
	* gthr-tpf.h: Likewise.
	* gthr-solaris.h: Likewise.
	* gthr-posix.h: Likewise.
	* gthr-posix95.h: Likewise.
	* config/darwin.c (darwin_encode_section_info): static weakref
	variables are not necessarily defined in this translation unit.
	* doc/extend.texi (Function Attributes): Mention that an alias
	attribute creates a definition for the thing it's attached to.
	Change the documentation for weakref to say that the thing
	it's attached to must be static.

Index: gcc/testsuite/ChangeLog
2005-12-05  Geoffrey Keating  <geoffk@apple.com>

	* g++.old-deja/g++.abi/vtable2.C: Make weakrefs static.
	* gcc.dg/attr-weakref-1.c: Modify to not try to test public weakrefs,
	and to work on Darwin.
	* gcc.dg/attr-weakref-1b.c: New file.
	* gcc.dg/attr-weakref-2.c: New test.
	* gcc.dg/darwin-weakref-1.c: New test.

From-SVN: r108074

1 files changed, 17 insertions, 11 deletions

diff --git a/gcc/varasm.c b/gcc/varasm.c
index fa181e1..5e59f3a 100644
--- a/gcc/varasm.c
+++ b/gcc/varasm.c
@@ -4508,10 +4508,6 @@ weak_finish_1 (tree decl)
   if (! TREE_USED (decl))
     return;
 
-  if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl))
-      && lookup_attribute ("alias", DECL_ATTRIBUTES (decl)))
-    return;
-
 #ifdef ASM_WEAKEN_DECL
   ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
 #else
@@ -4878,6 +4874,8 @@ assemble_alias (tree decl, tree target)
 	  TREE_CHAIN (alias) = target;
 #endif
 	}
+      if (TREE_PUBLIC (decl))
+	error ("weakref %q+D must have static linkage", decl);
     }
   else
     {
@@ -5619,21 +5617,29 @@ default_binds_local_p_1 (tree exp, int shlib)
   /* A non-decl is an entry in the constant pool.  */
   if (!DECL_P (exp))
     local_p = true;
+  /* Weakrefs may not bind locally, even though the weakref itself is
+     always static and therefore local.  */
+  else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp)))
+    local_p = false;
   /* Static variables are always local.  */
   else if (! TREE_PUBLIC (exp))
     local_p = true;
-  /* A variable is local if the user explicitly tells us so.  */
-  else if (DECL_VISIBILITY_SPECIFIED (exp) && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
+  /* A variable is local if the user has said explicitly that it will
+     be.  */
+  else if (DECL_VISIBILITY_SPECIFIED (exp) 
+	   && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
     local_p = true;
-  /* Otherwise, variables defined outside this object may not be local.  */
+  /* Variables defined outside this object might not be local.  */
   else if (DECL_EXTERNAL (exp))
     local_p = false;
-  /* Linkonce and weak data are never local.  */
-  else if (DECL_ONE_ONLY (exp) || DECL_WEAK (exp))
-    local_p = false;
-  /* If none of the above and visibility is not default, make local.  */
+  /* If defined in this object and visibility is not default, must be
+     local.  */
   else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
     local_p = true;
+  /* Default visibility weak data can be overridden by a strong symbol
+     in another module and so are not local.  */
+  else if (DECL_WEAK (exp))
+    local_p = false;
   /* If PIC, then assume that any global name can be overridden by
      symbols resolved from other modules.  */
   else if (shlib)