use the thunk in the code area in the case of Litarals (instead of copying it to the heap)

interpreter/code.c

@@ -297,7 +297,7 @@ void exec(Code* expr, int frame_ptr, int root_frame_ptr)
                 }
             }
         case CT_LIT:
-            set_return(root_frame_ptr, updateT(get_dst(root_frame_ptr), &((LitEntry*) expr)->thunk));
+            set_return(root_frame_ptr, &((LitEntry*) expr)->thunk);
             destroy_stack_frame(root_frame_ptr);
             return;               
         case CT_SELECT: