From 81831733af68134c89c389f69affde4d6329e225 Mon Sep 17 00:00:00 2001
From: Mike Williamson <mike.williamson@xtxmarkets.com>
Date: Mon, 19 Oct 2015 19:36:41 +0100
Subject: [PATCH] Fix potential race condition bug

---
 tds.go | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tds.go b/tds.go
index 16718ee4..2087e713 100644
--- a/tds.go
+++ b/tds.go
@@ -824,7 +824,8 @@ func dialConnection(p *connectParams) (conn net.Conn, err error) {
 			}
 		}
 	}
-	if err != nil {
+	// Can't do the usual err != nil check, as it is possible to have gotten an error before a successful connection
+	if conn == nil {
 		f := "Unable to open tcp connection with host '%v:%v': %v"
 		return nil, fmt.Errorf(f, p.host, p.port, err.Error())
 	}