Re: [RFC PATCH 3/3] Cygwin: add fast-path for posix_spawn(p)

[Yuyi Wang]

It would be better to handle `POSIX_SPAWN_SETSIGDEF` in the fast path, because
Rust usually sets SIGPIPE to SIG_IGN, but wants to recover it to SIG_DFL in the
child processes.

--
Yuyi Wang