diff --git a/sphinx/pycode/__init__.py b/sphinx/pycode/__init__.py
index e006ce160..26d3579dd 100644
--- a/sphinx/pycode/__init__.py
+++ b/sphinx/pycode/__init__.py
@@ -74,6 +74,7 @@ class ClassAttrVisitor(pytree.NodeVisitor):
                 self.collected.append((name, doc))
 
     def visit_funcdef(self, node):
+        # don't descend into functions -- nothing interesting there
         return