1 files changed, 7 insertions, 9 deletions

diff --git a/class.c b/class.c
index cf1731c1ab..1545cc0b9f 100644
--- a/class.c
+++ b/class.c
@@ -30,8 +30,6 @@
 #include "ruby/st.h"
 #include "vm_core.h"
 
-#define id_attached id__attached__
-
 #define METACLASS_OF(k) RBASIC(k)->klass
 #define SET_METACLASS_OF(k, cls) RBASIC_SET_CLASS(k, cls)
 
@@ -615,7 +613,7 @@ rb_singleton_class_clone_and_attach(VALUE obj, VALUE attach)
     // attached to an object other than `obj`. In which case `obj` does not have
     // a material singleton class attached yet and there is no singleton class
     // to clone.
-    if (!(FL_TEST(klass, FL_SINGLETON) && rb_attr_get(klass, id_attached) == obj)) {
+    if (!(FL_TEST(klass, FL_SINGLETON) && RCLASS_ATTACHED_OBJECT(klass) == obj)) {
         // nothing to clone
         return klass;
     }
@@ -668,7 +666,7 @@ void
 rb_singleton_class_attached(VALUE klass, VALUE obj)
 {
     if (FL_TEST(klass, FL_SINGLETON)) {
-        rb_class_ivar_set(klass, id_attached, obj);
+        RCLASS_SET_ATTACHED_OBJECT(klass, obj);
     }
 }
 
@@ -682,13 +680,13 @@ rb_singleton_class_attached(VALUE klass, VALUE obj)
 static int
 rb_singleton_class_has_metaclass_p(VALUE sklass)
 {
-    return rb_attr_get(METACLASS_OF(sklass), id_attached) == sklass;
+    return RCLASS_ATTACHED_OBJECT(METACLASS_OF(sklass)) == sklass;
 }
 
 int
 rb_singleton_class_internal_p(VALUE sklass)
 {
-    return (RB_TYPE_P(rb_attr_get(sklass, id_attached), T_CLASS) &&
+    return (RB_TYPE_P(RCLASS_ATTACHED_OBJECT(sklass), T_CLASS) &&
             !rb_singleton_class_has_metaclass_p(sklass));
 }
 
@@ -1677,7 +1675,7 @@ rb_class_attached_object(VALUE klass)
         rb_raise(rb_eTypeError, "`%"PRIsVALUE"' is not a singleton class", klass);
     }
 
-    return rb_attr_get(klass, id_attached);
+    return RCLASS_ATTACHED_OBJECT(klass);
 }
 
 static void
@@ -2206,7 +2204,7 @@ singleton_class_of(VALUE obj)
 
     klass = METACLASS_OF(obj);
     if (!(FL_TEST(klass, FL_SINGLETON) &&
-          rb_attr_get(klass, id_attached) == obj)) {
+          RCLASS_ATTACHED_OBJECT(klass) == obj)) {
         klass = rb_make_metaclass(obj, klass);
     }
 
@@ -2245,7 +2243,7 @@ rb_singleton_class_get(VALUE obj)
     }
     klass = METACLASS_OF(obj);
     if (!FL_TEST(klass, FL_SINGLETON)) return Qnil;
-    if (rb_attr_get(klass, id_attached) != obj) return Qnil;
+    if (RCLASS_ATTACHED_OBJECT(klass) != obj) return Qnil;
     return klass;
 }