#10111: minor problems in 2.7 FILE* API docs.
diff --git a/Doc/c-api/init.rst b/Doc/c-api/init.rst
index 79c96e4..f8ab642 100644
--- a/Doc/c-api/init.rst
+++ b/Doc/c-api/init.rst
@@ -413,6 +413,7 @@
 ============================================
 
 .. index::
+   single: GIL
    single: global interpreter lock
    single: interpreter lock
    single: lock, interpreter