From 08c64842982b4c9331b3e027f08e8e3785865465 Mon Sep 17 00:00:00 2001
From: Leorize <alaviss@users.noreply.github.com>
Date: Sat, 22 Sep 2018 11:24:29 +0700
Subject: [PATCH] ioselectors_poll: don't pollRemove() if not needed

pollAdd() is called only if events set isn't empty.
---
 lib/pure/ioselects/ioselectors_poll.nim | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/pure/ioselects/ioselectors_poll.nim b/lib/pure/ioselects/ioselectors_poll.nim
index 9d708b0c1d..103a2242cf 100644
--- a/lib/pure/ioselects/ioselectors_poll.nim
+++ b/lib/pure/ioselects/ioselectors_poll.nim
@@ -172,8 +172,9 @@ proc unregister*[T](s: Selector[T], fd: int|SocketHandle) =
   doAssert(pkey.ident != InvalidIdent,
            "Descriptor [" & $fdi & "] is not registered in the queue!")
   pkey.ident = InvalidIdent
-  pkey.events = {}
-  s.pollRemove(fdi.cint)
+  if pkey.events != {}:
+    pkey.events = {}
+    s.pollRemove(fdi.cint)
 
 proc unregister*[T](s: Selector[T], ev: SelectEvent) =
   let fdi = int(ev.rfd)