From: nobu.nokada@...
Date: 2002-10-21T10:32:06+09:00
Subject: Re: rb_class_new_instance question

Hi,

At Mon, 21 Oct 2002 08:52:13 +0900,
Tim Hunter wrote:
> However, if I create a new instance from C using rb_class_new_instance, 
> the statement "@scene = nil" causes the length attribute to become a 
> very large value. self.length may be 135674608, for example (but it's 
> not necessarily the same from time to time).

Underlying rb_obj_alloc() works for only T_OBJECT classes.  You
need to do like as `rb_funcall2(klass, new, argc, argv);'.
In 1.7, this behavior has been fixed.

This patch can fix it, but it would be difficult in extconf.rb
to distinguish wheather rb_class_new_instance() works for such
classes.


Index: eval.c
===================================================================
RCS file: /cvs/ruby/src/ruby/eval.c,v
retrieving revision 1.137.2.133
diff -u -2 -p -r1.137.2.133 eval.c
--- eval.c	17 Oct 2002 07:25:36 -0000	1.137.2.133
+++ eval.c	21 Oct 2002 01:22:44 -0000
@@ -453,5 +453,5 @@ rb_method_boundp(klass, id, ex)
 }
 
-static ID init, eqq, each, aref, aset, match, to_ary;
+static ID init, new, eqq, each, aref, aset, match, to_ary;
 static ID missing, added, singleton_added;
 static ID __id__, __send__;
@@ -5732,6 +5732,5 @@ rb_class_new_instance(argc, argv, klass)
 	rb_raise(rb_eTypeError, "can't create instance of virtual class");
     }
-    obj = rb_obj_alloc(klass);
-    rb_obj_call_init(obj, argc, argv);
+    obj = rb_funcall2(klass, new, argc, argv);
 
     return obj;
@@ -5959,4 +5958,5 @@ Init_eval()
 {
     init = rb_intern("initialize");
+    new = rb_intern("new");
     eqq = rb_intern("===");
     each = rb_intern("each");


-- 
Nobu Nakada