diff --git a/ChangeLog b/ChangeLog
index 3a5c72b2e9..445940b295 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,9 +1,13 @@
-Wed May  1 11:38:37 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+Wed May  1 11:40:25 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* defs/id.def (predefined): add "idProc".
 
+	* eval.c (frame_func_id): use predefined IDs.
+
 	* proc.c (mnew, mproc, mlambda): use predefined IDs.
 
+	* vm.c (rb_vm_control_frame_id_and_class): ditto.
+
 	* vm.c (Init_VM): ditto.
 
 Tue Apr 30 23:18:00 2013  Zachary Scott  <zachary@zacharyscott.net>
diff --git a/eval.c b/eval.c
index 79f4a0add7..3880a0edce 100644
--- a/eval.c
+++ b/eval.c
@@ -860,7 +860,7 @@ frame_func_id(rb_control_frame_t *cfp)
 	if (RUBY_VM_IFUNC_P(iseq)) {
 	    NODE *ifunc = (NODE *)iseq;
 	    if (ifunc->nd_aid) return ifunc->nd_aid;
-	    return rb_intern("<ifunc>");
+	    return idIFUNC;
 	}
 	me_local = method_entry_of_iseq(cfp, iseq);
 	if (me_local) {
@@ -890,7 +890,7 @@ frame_called_id(rb_control_frame_t *cfp)
 	if (RUBY_VM_IFUNC_P(iseq)) {
 	    NODE *ifunc = (NODE *)iseq;
 	    if (ifunc->nd_aid) return ifunc->nd_aid;
-	    return rb_intern("<ifunc>");
+	    return idIFUNC;
 	}
 	me_local = method_entry_of_iseq(cfp, iseq);
 	if (me_local) {
diff --git a/vm.c b/vm.c
index 03057bef1c..c6c972032e 100644
--- a/vm.c
+++ b/vm.c
@@ -1460,7 +1460,7 @@ rb_vm_control_frame_id_and_class(const rb_control_frame_t *cfp, ID *idp, VALUE *
     }
     while (iseq) {
 	if (RUBY_VM_IFUNC_P(iseq)) {
-	    if (idp) CONST_ID(*idp, "<ifunc>");
+	    if (idp) *idp = idIFUNC;
 	    if (klassp) *klassp = 0;
 	    return 1;
 	}