This builds with both boost 1.84 and boost 1.87.

Merging the patch from https://946488.bugs.gentoo.org/attachment.cgi?id=914160
into what we had wasn't hard but not entirely mechanical, so a runtime
check by someone who uses this would be nice.

kea's changelog only mentions a build fix for 1.87 only for the 2.7.x
development version, so we'll get to carry patches for a while whether
we update or not.

Index: Makefile
===================================================================
RCS file: /cvs/ports/net/kea/Makefile,v
diff -u -p -r1.41 Makefile
--- Makefile	17 Dec 2024 07:42:47 -0000	1.41
+++ Makefile	20 Apr 2025 18:08:34 -0000
@@ -2,7 +2,7 @@ COMMENT=	high-performance and extensible
 
 VERSION=	2.4.1
 PORTROACH=	limitw:1,even
-REVISION=	0
+REVISION=	1
 
 DISTNAME=	kea-${VERSION}
 PKGNAME-main=	kea-${VERSION:S/-P/pl/}
Index: patches/patch-src_lib_asiolink_io_service_cc
===================================================================
RCS file: /cvs/ports/net/kea/patches/patch-src_lib_asiolink_io_service_cc,v
diff -u -p -r1.1 patch-src_lib_asiolink_io_service_cc
--- patches/patch-src_lib_asiolink_io_service_cc	17 Dec 2024 07:42:47 -0000	1.1
+++ patches/patch-src_lib_asiolink_io_service_cc	20 Apr 2025 17:36:32 -0000
@@ -1,38 +1,106 @@
 https://github.com/isc-projects/kea/pull/143
+https://946488.bugs.gentoo.org/attachment.cgi?id=914160
 
 Index: src/lib/asiolink/io_service.cc
 --- src/lib/asiolink/io_service.cc.orig
 +++ src/lib/asiolink/io_service.cc
-@@ -25,7 +25,7 @@ class IOServiceImpl { (public)
+@@ -24,8 +24,7 @@ class IOServiceImpl { (private)
+ public:
      /// \brief The constructor
      IOServiceImpl() :
-         io_service_(),
+-        io_service_(),
 -        work_(new boost::asio::io_service::work(io_service_)) {
-+        work_(boost::asio::make_work_guard(io_service_)) {
++        io_context_() {
      };
  
      /// \brief The destructor.
-@@ -73,7 +73,7 @@ class IOServiceImpl { (public)
+@@ -37,7 +36,7 @@ class IOServiceImpl { (private)
+     /// This method does not return control to the caller until
+     /// the \c stop() method is called via some handler.
+     void run() {
+-        io_service_.run();
++        io_context_.run();
+     };
+ 
+     /// \brief Run the underlying event loop for a single event.
+@@ -46,7 +45,7 @@ class IOServiceImpl { (private)
+     /// first handler has completed.  (If no handlers are ready when
+     /// it is run, it will block until one is.)
+     void run_one() {
+-        io_service_.run_one();
++        io_context_.run_one();
+     };
+ 
+     /// \brief Run the underlying event loop for a ready events.
+@@ -54,32 +53,32 @@ class IOServiceImpl { (private)
+     /// This method executes handlers for all ready events and returns.
+     /// It will return immediately if there are no ready events.
+     void poll() {
+-        io_service_.poll();
++        io_context_.poll();
+     };
+ 
+     /// \brief Stop the underlying event loop.
+     ///
+     /// This will return the control to the caller of the \c run() method.
+     void stop() {
+-        io_service_.stop();
++        io_context_.stop();
+     }
+ 
+     /// \brief Indicates if the IOService has been stopped.
+     ///
+     /// \return true if the IOService has been stopped, false otherwise.
+     bool stopped() const {
+-        return (io_service_.stopped());
++        return (io_context_.stopped());
+     }
  
      /// \brief Restarts the IOService in preparation for a subsequent \c run() invocation.
      void restart() {
 -        io_service_.reset();
-+        io_service_.restart();
++        io_context_.restart();
      }
  
      /// \brief Removes IO service work object to let it finish running
-@@ -96,12 +96,12 @@ class IOServiceImpl { (public)
+     /// when all handlers have been invoked.
+     void stopWork() {
+-        work_.reset();
++        io_context_.stop();
+     }
+ 
+     /// \brief Return the native \c io_service object used in this wrapper.
+@@ -88,20 +87,19 @@ class IOServiceImpl { (private)
+     /// that share the same \c io_service with the authoritative server.
+     /// It will eventually be removed once the wrapper interface is
+     /// generalized.
+-    boost::asio::io_service& get_io_service() {
+-        return (io_service_);
++    boost::asio::io_context& get_io_context() {
++        return (io_context_);
+     }
+ 
+     /// \brief Post a callback on the IO service
      ///
      /// \param callback The callback to be run on the IO service.
      void post(const std::function<void ()>& callback) {
 -        io_service_.post(callback);
-+        boost::asio::post(io_service_, callback);
++        boost::asio::post(io_context_, callback);
      }
  
  private:
-     boost::asio::io_service io_service_;
+-    boost::asio::io_service io_service_;
 -    boost::shared_ptr<boost::asio::io_service::work> work_;
-+    boost::asio::executor_work_guard<boost::asio::io_service::executor_type> work_;
++    boost::asio::io_context io_context_;
  };
  
  IOService::IOService() : io_impl_(new IOServiceImpl()) {
+@@ -147,7 +145,7 @@ IOService::stopWork() {
+ 
+ boost::asio::io_service&
+ IOService::get_io_service() {
+-    return (io_impl_->get_io_service());
++    return (io_impl_->get_io_context());
+ }
+ 
+ void