diff --git a/.rdoc_options b/.rdoc_options
index 7325a10edf..a0dc1d0a31 100644
--- a/.rdoc_options
+++ b/.rdoc_options
@@ -10,7 +10,7 @@ rdoc_include:
 
 exclude:
 - \Alib/irb
-- .gemspec\z
+- \.gemspec\z
 
 autolink_excluded_words:
 - Class