* gc.c (id2ref): unmarked object is already dead while lazy

sweeping, and to it cannot come back since other objects
  referred from it might have been freed already.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@33219 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,9 @@
+Thu Sep  8 07:33:12 2011  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* gc.c (id2ref): unmarked object is already dead while lazy
+	  sweeping, and to it cannot come back since other objects
+	  referred from it might have been freed already.
+
 Wed Sep  8 03:48:00 2011  Ayumu AIZAWA  <ayumu.aizawa@gmail.com>
 
 	* ext/readline/README.ja:

gc.c

@@ -390,6 +390,8 @@ int *ruby_initial_gc_stress_ptr = &rb_objspace.gc_stress;
 #define global_List		objspace->global_list
 #define ruby_gc_stress		objspace->gc_stress
 
+#define is_lazy_sweeping(objspace) ((objspace)->heap.sweep_slots != 0)
+
 static void rb_objspace_call_finalizer(rb_objspace_t *objspace);
 
 #if defined(ENABLE_VM_OBJSPACE) && ENABLE_VM_OBJSPACE
@@ -3130,7 +3132,8 @@ id2ref(VALUE obj, VALUE objid)
 	BUILTIN_TYPE(ptr) > T_FIXNUM || BUILTIN_TYPE(ptr) == T_ICLASS) {
 	rb_raise(rb_eRangeError, "%p is not id value", p0);
     }
-    if (BUILTIN_TYPE(ptr) == 0 || RBASIC(ptr)->klass == 0) {
+    if (BUILTIN_TYPE(ptr) == 0 || RBASIC(ptr)->klass == 0 ||
+	(is_lazy_sweeping(objspace) && !(RBASIC(ptr)->flags & FL_MARK))) {
 	rb_raise(rb_eRangeError, "%p is recycled object", p0);
     }
     return (VALUE)ptr;