Give the optimiser a helping hand by making some coroutine_ref members const.

Author: chriskohlhoff

asio/include/asio/coroutine.hpp

@@ -328,8 +328,8 @@ class coroutine_ref
 private:
   void operator=(const coroutine_ref&);
   int& value_;
-  const asio::error_code* ec_;
-  void** async_result_;
+  const asio::error_code* const ec_;
+  void** const async_result_;
   bool modified_;
 };
 

asio/include/asio/go.hpp

@@ -172,8 +172,8 @@ class basic_stackless_context
   detail::shared_ptr<detail::stackless_impl_base<Handler> > stackless_impl_;
   Handler& handler_;
   coroutine* coroutine_;
-  const asio::error_code* throw_ec_;
-  void** async_result_;
+  const asio::error_code* const throw_ec_;
+  void** const async_result_;
   asio::error_code* ec_;
 };