index 3364da5..d475b03 100644
--- variable.c
+++ variable.c
@@ -1129,13 +1129,7 @@ rb_ivar_lookup(VALUE obj, ID id, VALUE undef)
 VALUE
 rb_ivar_get(VALUE obj, ID id)
 {
-    VALUE iv = rb_ivar_lookup(obj, id, Qundef);
-
-    if (iv == Qundef) {
-	rb_warning("instance variable %"PRIsVALUE" not initialized", QUOTE_ID(id));
-	iv = Qnil;
-    }
-    return iv;
+    return rb_ivar_lookup(obj, id, Qnil);
 }
 
 VALUE
index 05ed3c6..7b250ce 100644
--- vm_insnhelper.c
+++ vm_insnhelper.c
@@ -493,7 +493,7 @@ vm_getivar(VALUE obj, ID id, IC ic, rb_call_info_t *ci, int is_attr)
 {
 #if USE_IC_FOR_IVAR
     if (RB_TYPE_P(obj, T_OBJECT)) {
-	VALUE val = Qundef;
+	VALUE val = Qnil;
 	VALUE klass = RBASIC(obj)->klass;
 
 	if (LIKELY((!is_attr && ic->ic_serial == RCLASS_SERIAL(klass)) ||
@@ -528,10 +528,6 @@ vm_getivar(VALUE obj, ID id, IC ic, rb_call_info_t *ci, int is_attr)
 	    }
 	}
 
-	if (UNLIKELY(val == Qundef)) {
-	    if (!is_attr) rb_warning("instance variable %s not initialized", rb_id2name(id));
-	    val = Qnil;
-	}
 	return val;
     }
 #endif	/* USE_IC_FOR_IVAR */