From 0bfe012a6ebe564dc987677c37de754ec32eb53d Mon Sep 17 00:00:00 2001
From: Pavel Emelyanov <xemul@scylladb.com>
Date: Fri, 31 May 2024 15:28:43 +0300
Subject: [PATCH] sharded: Mark invoke_on_others() helper lambda mutable
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Otherwise mutable invoke-on-others lambdas fail to compile

   sharded<foo> f;
   f.invoke_on_others([x] (foo& f) mutable { ... });

generates

/home/xemul/src/seastar/include/seastar/core/future.hh:2074:11: error: no type named ‘type’ in ‘struct std::invoke_result<const invoke_on_modifiers::do_run_test_case() const::<lambda(invoke_on_modifiers::do_run_test_case() const::checker&)>&, invoke_on_modifiers::do_run_test_case() const::checker&>’
 2074 |     using futurator = futurize<std::invoke_result_t<Func, Args&&...>>;
      |           ^~~~~~~~~

The invoke_on_all() has its helper lambda mutable so

    sharded<foo> f;
    f.invoke_on_all([x] (foo& x) mutable { ... });

compiles.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
---
 include/seastar/core/sharded.hh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/seastar/core/sharded.hh b/include/seastar/core/sharded.hh
index 53713ea50ff..36a58811abc 100644
--- a/include/seastar/core/sharded.hh
+++ b/include/seastar/core/sharded.hh
@@ -780,7 +780,7 @@ sharded<Service>::invoke_on_others(smp_submit_to_options options, Func func, Arg
     static_assert(std::is_same_v<futurize_t<std::invoke_result_t<Func, Service&, Args...>>, future<>>,
                   "invoke_on_others()'s func must return void or future<>");
   try {
-    return invoke_on_all(options, [orig = this_shard_id(), func = std::move(func), args = std::tuple(std::move(args)...)] (Service& s) -> future<> {
+    return invoke_on_all(options, [orig = this_shard_id(), func = std::move(func), args = std::tuple(std::move(args)...)] (Service& s) mutable -> future<> {
         return this_shard_id() == orig ? make_ready_future<>() : futurize_apply(func, std::tuple_cat(std::forward_as_tuple(s), args));;
     });
   } catch (...) {