diff --git a/ChangeLog b/ChangeLog
index 96a8ad0c6c..7bbc78eaef 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Sep 29 10:26:18 2005  Tanaka Akira  <akr@m17n.org>
+
+	* ext/dl/cptr.c (rb_dlptr_s_to_ptr): abolish sizeof(FILE).
+	  [ruby-dev:27317]
+
 Thu Sep 29 10:15:14 2005  Tanaka Akira  <akr@m17n.org>
 
 	* lib/open-uri.rb (:proxy_http_basic_authentication): new option.
diff --git a/ext/dl/cptr.c b/ext/dl/cptr.c
index 70cb640580..fe83c7adf6 100644
--- a/ext/dl/cptr.c
+++ b/ext/dl/cptr.c
@@ -426,7 +426,7 @@ rb_dlptr_s_to_ptr(VALUE self, VALUE val)
 #else
 	fp = fptr->f;
 #endif
-	return rb_dlptr_new(fp, sizeof(FILE), NULL);
+	return rb_dlptr_new(fp, 0, NULL);
     }
     else if( rb_obj_is_kind_of(val, rb_cString) == Qtrue ){
         char *ptr = StringValuePtr(val);