diff --git a/includes/common.inc b/includes/common.inc
index 690c00478a..dc6720150b 100644
--- a/includes/common.inc
+++ b/includes/common.inc
@@ -8017,8 +8017,14 @@ function entity_extract_ids($entity_type, $entity) {
   $info = entity_get_info($entity_type);
 
   // Objects being created might not have id/vid yet.
-  $id = isset($entity->{$info['entity keys']['id']}) ? $entity->{$info['entity keys']['id']} : NULL;
-  $vid = ($info['entity keys']['revision'] && isset($entity->{$info['entity keys']['revision']})) ? $entity->{$info['entity keys']['revision']} : NULL;
+  if (!empty($info['entity keys'])) {
+    $id = isset($entity->{$info['entity keys']['id']}) ? $entity->{$info['entity keys']['id']} : NULL;
+    $vid = ($info['entity keys']['revision'] && isset($entity->{$info['entity keys']['revision']})) ? $entity->{$info['entity keys']['revision']} : NULL;
+  }
+  else {
+    $id = NULL;
+    $vid = NULL;
+  }
 
   if (!empty($info['entity keys']['bundle'])) {
     // Explicitly fail for malformed entities missing the bundle property.