diff --git a/core/lib/Drupal/Core/Entity/Field/FieldDefinition.php b/core/lib/Drupal/Core/Entity/Field/FieldDefinition.php
index dbc944e..ef79967 100644
--- a/core/lib/Drupal/Core/Entity/Field/FieldDefinition.php
+++ b/core/lib/Drupal/Core/Entity/Field/FieldDefinition.php
@@ -197,7 +197,7 @@ public function isFieldRequired() {
    *   The object itself for chaining.
    */
   public function setFieldRequired($required) {
-    return $this->definition['required'] = $required;
+    $this->definition['required'] = $required;
     return $this;
   }