From c1fa8595def1ea0b7476822b55ceb03bbe6ecc67 Mon Sep 17 00:00:00 2001
From: Thilo Graf <dbt@novatux.de>
Date: Thu, 4 Jul 2024 16:08:36 +0200
Subject: [PATCH] system/ping.cpp: Conditionally use register keyword for
 backward compatibility;

remove for C++17 and later where it is not allowed
---
 src/system/ping.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/system/ping.cpp b/src/system/ping.cpp
index 7b1f87505..912deb937 100644
--- a/src/system/ping.cpp
+++ b/src/system/ping.cpp
@@ -46,7 +46,11 @@ static int   sock = -1;
 static int 
 in_checksum( u_short *buf, int len )
 {
-  register long sum = 0;
+#if __cplusplus < 201703L
+    register long sum = 0; // Use register for older standards
+#else
+    long sum = 0; // register keyword is not allowed in C++17 and later
+#endif
   u_short  answer = 0;
 
   while( len > 1 ){