diff --git a/lib/risc/interpreter.rb b/lib/risc/interpreter.rb
index 2e27c04d..cbcf7b2b 100644
--- a/lib/risc/interpreter.rb
+++ b/lib/risc/interpreter.rb
@@ -270,7 +270,7 @@ module Risc
       else
         raise "un-implemented syscall #{name}"
       end
-      set_register( :syscall_1 , ret_value ) # syscalls return into syscall_1
+      set_register( std_reg(:syscall_1) , ret_value ) # syscalls return into syscall_1
       true
     end
 
diff --git a/lib/slot_machine/macro/macro.rb b/lib/slot_machine/macro/macro.rb
index 31fa825b..e4655659 100644
--- a/lib/slot_machine/macro/macro.rb
+++ b/lib/slot_machine/macro/macro.rb
@@ -43,7 +43,7 @@ module SlotMachine
     # This instance is filled with os return value
     def self.restore_message(builder)
       r8 = Risc::RegisterValue.new( :saved_message , :Message).set_compiler(builder.compiler)
-      tmp = Risc::RegisterValue.new( :integer_tmp , :Integer).set_compiler(builder.compiler)
+      tmp = Risc::RegisterValue.new( :restore_integer_return , :Integer).set_compiler(builder.compiler)
       builder.build do
         tmp << Risc.syscall_reg(1)
         message << r8
diff --git a/test/risc/interpreter/calling/test_puts.rb b/test/risc/interpreter/calling/test_puts.rb
index f29bbcf9..9072e826 100644
--- a/test/risc/interpreter/calling/test_puts.rb
+++ b/test/risc/interpreter/calling/test_puts.rb
@@ -25,7 +25,7 @@ module Risc
                  SlotToReg, Transfer, Syscall, NilClass,] #55
        assert_equal "Hello again" , @interpreter.stdout
        assert_equal Integer , get_return.class
-       assert_equal 11 , get_return.to_string #bytes written
+       assert_equal 11 , get_return #bytes written
     end
     def test_call
       cal =  main_ticks(11)
@@ -44,12 +44,12 @@ module Risc
       done = main_ticks(25)
       assert_equal Syscall ,  done.class
       assert_equal "Hello again" , @interpreter.stdout
-      assert_equal 11 , @interpreter.get_register(:syscall_1)
+      assert_equal 11 , @interpreter.get_register(@interpreter.std_reg(:syscall_1))
     end
 
     def test_move_sys_return
       assert_transfer(26, :r0 ,:r1)
-      assert_equal 11 , @interpreter.get_register(:integer_tmp)
+      assert_equal 11 , @interpreter.get_register(@interpreter.std_reg(:syscall_1))
     end
     def test_restore_message
       assert_transfer(27, :r14 ,:r13)
diff --git a/test/slot_machine/macro/test_putstring.rb b/test/slot_machine/macro/test_putstring.rb
index 90d3268e..ec447f67 100644
--- a/test/slot_machine/macro/test_putstring.rb
+++ b/test/slot_machine/macro/test_putstring.rb
@@ -28,10 +28,10 @@ module SlotMachine
         assert_transfer s + 5 , "id_factory_.next_object" , :syscall_2
         assert_transfer s + 6 , :message , :saved_message
         assert_syscall s + 7 , :putstring
-        assert_transfer s + 8 , :syscall_1 , :integer_tmp
+        assert_transfer s + 8 , :syscall_1 , :restore_integer_return
         assert_transfer s + 9 , :saved_message , :message
         assert_slot_to_reg s + 10 ,:message , 5 , "message.return_value"
-        assert_reg_to_slot s + 11 , :integer_tmp  , "message.return_value" , 2
+        assert_reg_to_slot s + 11 , :restore_integer_return  , "message.return_value" , 2
         assert_slot_to_reg s + 12 ,:message , 5 , "message.return_value"
         assert_reg_to_slot s + 13 , "message.return_value"  , :message , 5
         assert_branch s + 14 , "return_label"