1 files changed, 3 insertions, 1 deletions
diff --git a/lib/rubygems/source.rb b/lib/rubygems/source.rb
index 4ae84cf532..37e03cdfae 100644
--- a/lib/rubygems/source.rb
+++ b/lib/rubygems/source.rb
@@ -35,6 +35,7 @@ class Gem::Source
     end
 
     @uri = uri
+    @update_cache = nil
   end
 
   ##
@@ -118,7 +119,8 @@ class Gem::Source
   # Returns true when it is possible and safe to update the cache directory.
 
   def update_cache?
-    @update_cache ||=
+    return @update_cache unless @update_cache.nil?
+    @update_cache =
       begin
         File.stat(Gem.user_home).uid == Process.uid
       rescue Errno::ENOENT