Allow waitpid(-1, Process::WNOHANG) to be woken if a waitpid(pid) is #10787
+43
−11
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...pending
If two threads are running, with one calling waitpid(-1, Process::WNOHANG), and another calling waitpid($some_pid), and then
$some_other_pid exits, we would expect the waitpid(-1, Process::WNOHANG) call to retrieve that exit status. However, it cannot actually do so until $some_pid also exits.
This patch fixes the issue by calling do_waitpid unconditionally in waitpid_wait; this will ensure that a waitpid -1 actually reaps something (after first checking that no PID-directed call wants the process).