From 91a3159ffabaa26cf0010cbe55b24703c7435348 Mon Sep 17 00:00:00 2001
From: Christopher Kohlhoff <chris@kohlhoff.com>
Date: Tue, 4 Apr 2023 20:16:35 +1000
Subject: [PATCH] Avoid evaluating concept when Executor1 is not an executor.

---
 include/boost/asio/basic_socket_acceptor.hpp | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/include/boost/asio/basic_socket_acceptor.hpp b/include/boost/asio/basic_socket_acceptor.hpp
index 4c26d51e..a9d1d25e 100644
--- a/include/boost/asio/basic_socket_acceptor.hpp
+++ b/include/boost/asio/basic_socket_acceptor.hpp
@@ -1925,8 +1925,10 @@ public:
   template <typename Executor1,
       BOOST_ASIO_COMPLETION_TOKEN_FOR(void (boost::system::error_code,
         typename Protocol::socket::template rebind_executor<
-          Executor1>::other)) MoveAcceptToken
-            BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
+          typename constraint<is_executor<Executor1>::value
+            || execution::is_executor<Executor1>::value,
+              Executor1>::type>::other)) MoveAcceptToken
+                BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
   BOOST_ASIO_INITFN_AUTO_RESULT_TYPE_PREFIX(MoveAcceptToken,
       void (boost::system::error_code,
         typename Protocol::socket::template rebind_executor<
@@ -2487,8 +2489,10 @@ public:
   template <typename Executor1,
       BOOST_ASIO_COMPLETION_TOKEN_FOR(void (boost::system::error_code,
         typename Protocol::socket::template rebind_executor<
-          Executor1>::other)) MoveAcceptToken
-            BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
+          typename constraint<is_executor<Executor1>::value
+            || execution::is_executor<Executor1>::value,
+              Executor1>::type>::other)) MoveAcceptToken
+                BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
   BOOST_ASIO_INITFN_AUTO_RESULT_TYPE_PREFIX(MoveAcceptToken,
       void (boost::system::error_code,
         typename Protocol::socket::template rebind_executor<