[exec] Cast the return value of the comma expression to `void`?

[hewillk]

There are two (perhaps more) places in [exec] where fold-expression is used to expand the function: [exec.when.all] and [exec.snd.expos]:

[](auto&, auto&, auto&... ops) noexcept -> void {
  (execution::start(ops), ...);
}

Do we need to convert the return result to void as LWG 3755 does to conform to the current best practice of the standard? Is this editorial, or does it require an LWG? Or maybe this is not necessary at all?

[frederick-vs-ja]

Does the return value of execution::start (execution::start_t::operator()) even make sense? If not, perhaps we should just submit an LWG issue to specify that execution::start always returns void.

FWIW, stdexec's start is already always returning void.

[jensmaurer]

Please submit as an LWG issue. The discussion around LWG3755 indicates there are some non-trivial considerations floating around.

[frederick-vs-ja]

LWG4143