diff --git a/Lib/distutils/cmd.py b/Lib/distutils/cmd.py
index 28d86179495..c544b864405 100644
--- a/Lib/distutils/cmd.py
+++ b/Lib/distutils/cmd.py
@@ -353,7 +353,7 @@ class install_misc (Command):
 
     def initialize_options (self):
         self.install_dir = None
-        self.outfiles = None
+        self.outfiles = []
 
     def _install_dir_from (self, dirname):
         self.set_undefined_options('install', (dirname, 'install_dir'))