diff --git a/core/modules/field/field.module b/core/modules/field/field.module
index 0f281b4..ed88892 100644
--- a/core/modules/field/field.module
+++ b/core/modules/field/field.module
@@ -990,9 +990,16 @@ function template_preprocess_field(&$variables, $hook) {
   if (!isset($default_attributes)) {
     $default_attributes = new Attribute;
   }
-  $variables['attributes'] = new Attribute;
-  $variables['title_attributes'] = new Attribute;
-  $variables['content_attributes'] = new Attribute;
+  // The default theme implementation for fields is a function.
+  // template_preprocess() (which initializes the attributes, title_attributes,
+  // and content_attributes arrays) does not run for theme function
+  // implementations. Additionally, Attribute objects for the three variables
+  // below only get instantiated for template file implementations, and we need
+  // Attribute objects for printing in both theme functions and template files.
+  // For best performance, we only instantiate Attribute objects when needed.
+  $variables['attributes'] = isset($variables['attributes']) ? new Attribute($variables['attributes']) : clone $default_attributes;
+  $variables['title_attributes'] = isset($variables['title_attributes']) ? new Attribute($variables['title_attributes']) : clone($default_attributes);
+  $variables['content_attributes'] = isset($variables['content_attributes']) ? new Attribute($variables['content_attributes']) : clone($default_attributes);
   foreach ($variables['items'] as $delta => $item) {
     $variables['item_attributes'][$delta] = isset($variables['item_attributes'][$delta]) ? new Attribute($variables['item_attributes'][$delta]) : clone($default_attributes);
   }
diff --git a/core/modules/rdf/rdf.module b/core/modules/rdf/rdf.module
index 526ef66..8e4d278 100644
--- a/core/modules/rdf/rdf.module
+++ b/core/modules/rdf/rdf.module
@@ -406,6 +406,12 @@ function rdf_preprocess_field(&$variables) {
           $variables['item_attributes'][$delta]['resource'] = file_create_url($item['entity']->getFileUri());
         }
       }
+      // Convert the item_attributes for this field item back into an Attribute
+      // object for printing. This is necessary because at this time this
+      // preprocess function overwrites $variables['item_attributes'][$delta],
+      // which is initialized as an Attribute object in
+      // template_preprocess_field().
+      $variables['item_attributes'][$delta] = new Attribute($variables['item_attributes'][$delta]);
     }
   }
 }