diff --git a/lib/register/passes/call_implementation.rb b/lib/register/passes/call_implementation.rb
index ea6af3e2..a265bd4f 100644
--- a/lib/register/passes/call_implementation.rb
+++ b/lib/register/passes/call_implementation.rb
@@ -12,7 +12,6 @@ module Register
       block.codes.dup.each do |code|
         next unless code.is_a? Virtual::MethodCall
         new_codes = []
-        slot = Virtual::Slot
         # move the current new_message to message
         new_codes << RegisterTransfer.new( RegisterReference.new_message_reg , RegisterReference.message_reg )
         # "roll out" self into its register
diff --git a/lib/register/passes/return_implementation.rb b/lib/register/passes/return_implementation.rb
index e17fe94d..eaf1ac24 100644
--- a/lib/register/passes/return_implementation.rb
+++ b/lib/register/passes/return_implementation.rb
@@ -1,7 +1,6 @@
 module Register
   class ReturnImplementation
     def run block
-      slot = Virtual::Slot
       block.codes.dup.each do |code|
         next unless code.is_a? Virtual::MethodReturn
         new_codes = []