Revert self-referencing finalizer warning [Feature #15974]

It has caused CI failures.

* d0cd0866d82a58933e5dccd073c753c0c2ad4eb5

  Disable GC during rb_objspace_reachable_object_p

* 89cef1c56b3a0f9c5e6ccc22a5044477a4fd16c1

  Version guard for [Feature #15974]

* 796eeb6339952d92ae1b353d450c7883e589852d.

  Fix up [Feature #15974]

* 928260c2a613bbdd4402c300e0bf86ae7562e52a.

  Warn in verbose mode on defining a finalizer that captures the object

1 files changed, 0 insertions, 64 deletions

diff --git a/gc.c b/gc.c
index 084923f510..2b7b039830 100644
--- a/gc.c
+++ b/gc.c
@@ -2954,8 +2954,6 @@ should_be_finalizable(VALUE obj)
     rb_check_frozen(obj);
 }
 
-static int rb_objspace_reachable_object_p(VALUE obj, VALUE root);
-
 /*
  *  call-seq:
  *     ObjectSpace.define_finalizer(obj, aProc=proc())
@@ -2965,10 +2963,6 @@ static int rb_objspace_reachable_object_p(VALUE obj, VALUE root);
  *  as an argument to <i>aProc</i>. If <i>aProc</i> is a lambda or
  *  method, make sure it can be called with a single argument.
  *
- *  In verbose mode (<code>-w</code>) a warning will be issued if
- *  the object is reachable from <i>aProc</i>, which may prevent
- *  finalization.
- *
  */
 
 static VALUE
@@ -2985,11 +2979,6 @@ define_final(int argc, VALUE *argv, VALUE os)
 	should_be_callable(block);
     }
 
-    if (RTEST(ruby_verbose)) {
-        if (rb_objspace_reachable_object_p(obj, block))
-            rb_warn("object is reachable from finalizer - it may never be run");
-    }
-
     return define_final0(obj, block);
 }
 
@@ -9337,59 +9326,6 @@ rb_objspace_reachable_objects_from_root(void (func)(const char *category, VALUE,
     POP_MARK_FUNC_DATA();
 }
 
-struct reachable_object_data {
-    VALUE obj;
-    VALUE set;
-};
-
-static void
-reachable_object_callback(VALUE child, void *dp)
-{
-    struct reachable_object_data *data = dp;
-    if (child == data->obj) {
-        rb_throw_obj(data->set, Qtrue);
-    }
-
-    // Maintain a set of objects already searched, so that we don't follow a cycle
-    if (rb_hash_lookup2(data->set, child, Qfalse))
-        return;
-    rb_hash_aset(data->set, child, Qtrue);
-
-    rb_objspace_reachable_objects_from(child, reachable_object_callback, data);
-}
-
-static VALUE
-call_reachable_object(RB_BLOCK_CALL_FUNC_ARGLIST(set, arg))
-{
-    struct reachable_object_data *data = (void *)arg;
-    VALUE obj = data->set;
-    data->set = rb_obj_hide(set);
-    gc_mark_children(&rb_objspace, obj);
-    rb_hash_clear(set);
-    return Qfalse;
-}
-
-static int
-rb_objspace_reachable_object_p(VALUE obj, VALUE root)
-{
-    rb_objspace_t *objspace = &rb_objspace;
-    int reachable = FALSE;
-    if (is_markable_object(objspace, obj)) {
-        struct reachable_object_data data = {obj, root};
-        struct mark_func_data_struct mfd = {&data, reachable_object_callback};
-        int prev_dont_gc = dont_gc;
-        enum ruby_tag_type state;
-
-        dont_gc = TRUE;
-        PUSH_MARK_FUNC_DATA(&mfd);
-        reachable = RTEST(rb_catch_protect(rb_ident_hash_new(), call_reachable_object, (VALUE)&data, &state));
-        POP_MARK_FUNC_DATA();
-        dont_gc = prev_dont_gc;
-        if (state) EC_JUMP_TAG(GET_EC(), state);
-    }
-    return reachable;
-}
-
 /*
   ------------------------ Extended allocator ------------------------
 */