Eagerly release predecessor operation state in let_value

pika-org · Nov 6, 2024 · 93d6d6f · 93d6d6f
1 parent 6ac54ed
commit 93d6d6f
Showing 1 changed file with 11 additions and 6 deletions.
diff --git a/libs/pika/execution/include/pika/execution/algorithms/let_value.hpp b/libs/pika/execution/include/pika/execution/algorithms/let_value.hpp
@@ -120,7 +120,7 @@ namespace pika::let_value_detail {
 
             // Operation state from connecting predecessor sender to
             // let_value_predecessor_receiver
-            predecessor_operation_state_type predecessor_op_state;
+            std::optional<predecessor_operation_state_type> predecessor_op_state;
 
             using predecessor_ts_type = pika::util::detail::prepend_t<
                 predecessor_value_types<std::tuple, pika::detail::variant>,
@@ -158,12 +158,14 @@ namespace pika::let_value_detail {
                 {
                     pika::execution::experimental::set_error(
                         PIKA_MOVE(r.receiver), PIKA_FORWARD(Error, error));
+                    r.op_state.predecessor_op_state.reset();
                 }
 
                 friend void tag_invoke(pika::execution::experimental::set_stopped_t,
                     let_value_predecessor_receiver&& r) noexcept
                 {
                     pika::execution::experimental::set_stopped(PIKA_MOVE(r.receiver));
+                    r.op_state.predecessor_op_state.reset();
                 };
 
                 struct start_visitor
@@ -238,6 +240,7 @@ namespace pika::let_value_detail {
                             op_state.predecessor_ts
                                 .template emplace<std::tuple<std::decay_t<Ts>...>>(
                                     PIKA_FORWARD(Ts, ts)...);
+                            // op_state.predecessor_op_state.reset();
                             pika::detail::visit(
                                 set_value_visitor{PIKA_MOVE(receiver), PIKA_MOVE(f), op_state},
                                 op_state.predecessor_ts);
@@ -266,10 +269,12 @@ namespace pika::let_value_detail {
 
             template <typename PredecessorSender_, typename Receiver_, typename F_>
             operation_state(PredecessorSender_&& predecessor_sender, Receiver_&& receiver, F_&& f)
-              : predecessor_op_state{pika::execution::experimental::connect(
-                    PIKA_FORWARD(PredecessorSender_, predecessor_sender),
-                    let_value_predecessor_receiver(
-                        PIKA_FORWARD(Receiver_, receiver), PIKA_FORWARD(F_, f), *this))}
+              : predecessor_op_state(pika::detail::with_result_of([&]() {
+                  return pika::execution::experimental::connect(
+                      PIKA_FORWARD(PredecessorSender_, predecessor_sender),
+                      let_value_predecessor_receiver(
+                          PIKA_FORWARD(Receiver_, receiver), PIKA_FORWARD(F_, f), *this));
+              }))
             {
             }
 
@@ -281,7 +286,7 @@ namespace pika::let_value_detail {
             friend void tag_invoke(
                 pika::execution::experimental::start_t, operation_state& os) noexcept
             {
-                pika::execution::experimental::start(os.predecessor_op_state);
+                pika::execution::experimental::start(*os.predecessor_op_state);
             }
         };