https://github.com/tessus/apachetop/pull/13

From f89ae55bb09eb1a67fc73555d149fb85f82bfbd6 Mon Sep 17 00:00:00 2001
From: Sam James <sam@gentoo.org>
Date: Tue, 14 Feb 2023 03:34:36 +0000
Subject: [PATCH] Fix C++17 compatibility (drop register keyword)

register doesn't do anything in any reasonable C++ compiler anyway, but
it was deprecated in C++14 and removed in C++17. Without this, apachetop
will fail to compile with Clang 16 which defaults to -std=c++17.

Bug: https://bugs.gentoo.org/894186
--- a/src/inlines.cc
+++ b/src/inlines.cc
@@ -4,10 +4,10 @@
 #define ONE_EIGHTH      4
 #define HIGH_BITS       (~((unsigned int)(~0) >> ONE_EIGHTH))
 
-inline unsigned int StringHash(register const char *str)
+inline unsigned int StringHash(const char *str)
 {
-	register unsigned int val;
-	register unsigned int i;
+	unsigned int val;
+	unsigned int i;
 
 	for (val = 0; *str; str++)
 	{
@@ -19,9 +19,9 @@ inline unsigned int StringHash(register const char *str)
 	return val;
 }
 
-inline unsigned int QuickHash(register const char *str)
+inline unsigned int QuickHash(const char *str)
 {
-	register unsigned int val, tmp;
+	unsigned int val, tmp;
 
 	for(val = 0 ; *str ; str++)
 	{
@@ -32,7 +32,7 @@ inline unsigned int QuickHash(register const char *str)
 	return val;
 }
 
-inline unsigned long TTHash(register const char *str)
+inline unsigned long TTHash(const char *str)
 {
 	unsigned long hash = 5381;
 	int c;
--- a/src/ohtbl.cc
+++ b/src/ohtbl.cc
@@ -13,7 +13,7 @@ static int primes[] = {101, 241, 499, 1009, 2003, 3001, 4001, 5003,
 
 int OAHash::getNextPrime(int size)
 {
-	register int *prime;
+	int *prime;
 	for (prime = &primes[0] ; *prime ; prime++)
 		if (*prime > size)
 			return *prime;
@@ -51,7 +51,7 @@ void OAHash::destroy(void)
 
 void *OAHash::insert(char *key, void *data)
 {
-	register unsigned int p, i;
+	unsigned int p, i;
 	void *d;
  
 	// Do not exceed the number of positions in the table.
@@ -81,7 +81,7 @@ void *OAHash::insert(char *key, void *data)
 
 int OAHash::remove(char *key)
 {
-	register unsigned int p, i;
+	unsigned int p, i;
 
 	for (i = 0; i < positions; ++i)
 	{
@@ -108,7 +108,7 @@ int OAHash::remove(char *key)
 
 void *OAHash::lookup(char *key)
 {
-	register unsigned int p, i;
+	unsigned int p, i;
 
 	for (i = 0; i < positions; ++i)
 	{
-- 
2.39.1