diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
index ecfd10a..8213659 100644
--- a/hw/misc/ivshmem.c
+++ b/hw/misc/ivshmem.c
@@ -1280,7 +1280,7 @@
     object_property_add_child(OBJECT(s), "internal-shm-backend", obj,
                               &error_abort);
     object_unref(obj);
-    user_creatable_complete(obj, &error_abort);
+    user_creatable_complete(USER_CREATABLE(obj), &error_abort);
     s->hostmem = MEMORY_BACKEND(obj);
 }
 
diff --git a/hw/virtio/virtio-rng.c b/hw/virtio/virtio-rng.c
index 855f1b4..30493a2 100644
--- a/hw/virtio/virtio-rng.c
+++ b/hw/virtio/virtio-rng.c
@@ -191,7 +191,7 @@
     if (vrng->conf.rng == NULL) {
         vrng->conf.default_backend = RNG_RANDOM(object_new(TYPE_RNG_RANDOM));
 
-        user_creatable_complete(OBJECT(vrng->conf.default_backend),
+        user_creatable_complete(USER_CREATABLE(vrng->conf.default_backend),
                                 &local_err);
         if (local_err) {
             error_propagate(errp, local_err);
diff --git a/include/qom/object_interfaces.h b/include/qom/object_interfaces.h
index 652a16d..682ba1d 100644
--- a/include/qom/object_interfaces.h
+++ b/include/qom/object_interfaces.h
@@ -51,14 +51,14 @@
 
 /**
  * user_creatable_complete:
- * @obj: the object whose complete() method is called if defined
+ * @uc: the user-creatable object whose complete() method is called if defined
  * @errp: if an error occurs, a pointer to an area to store the error
  *
  * Wrapper to call complete() method if one of types it's inherited
  * from implements USER_CREATABLE interface, otherwise the call does
  * nothing.
  */
-void user_creatable_complete(Object *obj, Error **errp);
+void user_creatable_complete(UserCreatable *uc, Error **errp);
 
 /**
  * user_creatable_can_be_deleted:
diff --git a/qom/object.c b/qom/object.c
index 547dcf9..eb770db 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -417,6 +417,7 @@
 {
     Error *local_err = NULL;
     Object *obj;
+    UserCreatable *uc;
 
     object_initialize(childobj, size, type);
     obj = OBJECT(childobj);
@@ -431,8 +432,9 @@
         goto out;
     }
 
-    if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) {
-        user_creatable_complete(obj, &local_err);
+    uc = (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE);
+    if (uc) {
+        user_creatable_complete(uc, &local_err);
         if (local_err) {
             object_unparent(obj);
             goto out;
@@ -590,6 +592,7 @@
     Object *obj;
     ObjectClass *klass;
     Error *local_err = NULL;
+    UserCreatable *uc;
 
     klass = object_class_by_name(typename);
     if (!klass) {
@@ -612,8 +615,9 @@
         goto error;
     }
 
-    if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) {
-        user_creatable_complete(obj, &local_err);
+    uc = (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE);
+    if (uc) {
+        user_creatable_complete(uc, &local_err);
         if (local_err) {
             object_unparent(obj);
             goto error;
diff --git a/qom/object_interfaces.c b/qom/object_interfaces.c
index 97b79b4..db85d1e 100644
--- a/qom/object_interfaces.c
+++ b/qom/object_interfaces.c
@@ -8,18 +8,10 @@
 #include "qapi/opts-visitor.h"
 #include "qemu/config-file.h"
 
-void user_creatable_complete(Object *obj, Error **errp)
+void user_creatable_complete(UserCreatable *uc, Error **errp)
 {
+    UserCreatableClass *ucc = USER_CREATABLE_GET_CLASS(uc);
 
-    UserCreatableClass *ucc;
-    UserCreatable *uc =
-        (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE);
-
-    if (!uc) {
-        return;
-    }
-
-    ucc = USER_CREATABLE_GET_CLASS(uc);
     if (ucc->complete) {
         ucc->complete(uc, errp);
     }
@@ -89,7 +81,7 @@
         goto out;
     }
 
-    user_creatable_complete(obj, &local_err);
+    user_creatable_complete(USER_CREATABLE(obj), &local_err);
     if (local_err) {
         object_property_del(object_get_objects_root(),
                             id, &error_abort);