diff --git a/lib/rdoc/rdoc.rb b/lib/rdoc/rdoc.rb
index 20ec2414e6..31a813f104 100644
--- a/lib/rdoc/rdoc.rb
+++ b/lib/rdoc/rdoc.rb
@@ -417,6 +417,7 @@ def parse_files files
 
     return [] if file_list.empty?
 
+    original_options = @options.dup
     @stats.begin_adding
 
     file_info = file_list.map do |filename|
@@ -425,6 +426,7 @@ def parse_files files
     end.compact
 
     @stats.done_adding
+    @options = original_options
 
     file_info
   end