From 4ee23e0b6e262d85cfba6f03a3be8f69bb9f9ba7 Mon Sep 17 00:00:00 2001
From: Remi Gacogne <remi.gacogne@powerdns.com>
Date: Tue, 17 Aug 2021 09:32:40 +0200
Subject: [PATCH] dnsdist: Avoid arithmetic on bitfields, as suggested by Otto

---
 pdns/dnsdist.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pdns/dnsdist.cc b/pdns/dnsdist.cc
index 8f3e34b114..900e2facdb 100644
--- a/pdns/dnsdist.cc
+++ b/pdns/dnsdist.cc
@@ -294,7 +294,7 @@ static void restoreFlags(struct dnsheader* dh, uint16_t origFlags)
 
 static uint16_t getRDAndCDFlagsFromDNSHeader(const struct dnsheader* dh)
 {
-  return static_cast<uint16_t>((dh->rd << FLAGS_RD_OFFSET) + (dh->cd << FLAGS_CD_OFFSET));
+  return static_cast<uint16_t>(dh->rd) << FLAGS_RD_OFFSET | static_cast<uint16_t>(dh->cd) << FLAGS_CD_OFFSET;
 }
 
 static bool fixUpQueryTurnedResponse(DNSQuestion& dq, const uint16_t origFlags)
-- 
2.47.2