From e0c4c97a465e78457fc19b130ccfebececc45bcf Mon Sep 17 00:00:00 2001
From: Marten Seemann <martenseemann@gmail.com>
Date: Fri, 1 Nov 2019 19:08:39 +0700
Subject: [PATCH] correctly handle nil tls.Configs in the http09.RoundTripper

---
 interop/http09/client.go | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/interop/http09/client.go b/interop/http09/client.go
index 1cee2320..8edcd67c 100644
--- a/interop/http09/client.go
+++ b/interop/http09/client.go
@@ -41,7 +41,10 @@ func (r *RoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
 	}
 	c, ok := r.clients[hostname]
 	if !ok {
-		tlsConf := r.TLSClientConfig.Clone()
+		tlsConf := &tls.Config{}
+		if r.TLSClientConfig != nil {
+			tlsConf = r.TLSClientConfig.Clone()
+		}
 		tlsConf.NextProtos = []string{h09alpn}
 		c = &client{
 			hostname: hostname,