[master] 2c6f24d Clarify things for Coverity

[Poul-Henning Kamp]

commit 2c6f24d26ed4852963f2ff7a55029f6d765f3c3d
Author: Poul-Henning Kamp <phk at FreeBSD.org>
Date:   Thu Apr 12 08:07:00 2018 +0000

    Clarify things for Coverity

diff --git a/bin/varnishtest/vtc_haproxy.c b/bin/varnishtest/vtc_haproxy.c
index 73f42b8..663a363 100644
--- a/bin/varnishtest/vtc_haproxy.c
+++ b/bin/varnishtest/vtc_haproxy.c
@@ -388,6 +388,7 @@ haproxy_build_backends(const struct haproxy *h, const char *vsb_data)
 		if (err != NULL)
 			vtc_fatal(h->vl,
 			    "Create listen socket failed: %s", err);
+		assert(sock > 0);
 
 		VTCP_myname(sock, addr, sizeof addr, port, sizeof port);
 		bprintf(buf, "%s_%s", h->name, p);