diff --git a/sphinx/themes/basic/genindex-single.html b/sphinx/themes/basic/genindex-single.html
index a771c587b..93fb9b332 100644
--- a/sphinx/themes/basic/genindex-single.html
+++ b/sphinx/themes/basic/genindex-single.html
@@ -37,7 +37,7 @@
 <table style="width: 100%" class="indextable"><tr>
   {%- for column in entries|slice(2) if column %}
   <td style="width: 33%" valign="top"><dl>
-    {%- for entryname, (links, subitems) in column %}
+    {%- for entryname, (links, subitems, _) in column %}
       {{ indexentries(entryname, links) }}
       {%- if subitems %}
       <dd><dl>