diff --git a/lib/rubygems/psych_tree.rb b/lib/rubygems/psych_tree.rb
index 7d17fc29cfe9e7..24857adb9d3c41 100644
--- a/lib/rubygems/psych_tree.rb
+++ b/lib/rubygems/psych_tree.rb
@@ -15,7 +15,7 @@ def visit_String(str)
       end
 
       def visit_Hash(o)
-        super(o.dup.delete_if {|_, v| v.nil? })
+        super(o.compact)
       end
 
       # Noop this out so there are no anchors