gproc_pool timer message leaks?

[leoliu]

I am investigating gproc_pool for pooling DB connections. It seems if the following timer expires its message will be left in current process's mailbox leading to a leak.

setup_wait({busy_wait, MS}, Pool) ->
    Ref = erlang:send_after(MS, self(), {claim, Pool}),
    {busy_wait, Ref}.

[uwiger]

That seems correct. The message would need to be consumed about here:
https://github.com/uwiger/gproc/blob/master/src/gproc_pool.erl#L570