From f4b1ad43d4e701538e60c5640032117c353577e2 Mon Sep 17 00:00:00 2001
From: Avi Kivity <avi@scylladb.com>
Date: Sat, 22 Jun 2024 00:13:04 +0300
Subject: [PATCH] gdb: protect debug::the_database from lto

Clang 18.1 with lto gained the ability to eliminate dead stores.
Since debug::the_database is write-only as far as the compiler understands
(it is read only by gdb), all writes to it are eliminated.

Protect writes to the variable by marking it volatile.

Closes scylladb/scylladb#22454
---
 debug.cc | 2 +-
 debug.hh | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/debug.cc b/debug.cc
index fac4aec30f..ad1f5f29c2 100644
--- a/debug.cc
+++ b/debug.cc
@@ -10,6 +10,6 @@
 
 namespace debug {
 
-seastar::sharded<replica::database>* the_database = nullptr;
+seastar::sharded<replica::database>* volatile the_database = nullptr;
 
 }
diff --git a/debug.hh b/debug.hh
index b0874e1959..39f9ff84eb 100644
--- a/debug.hh
+++ b/debug.hh
@@ -16,7 +16,7 @@ class database;
 
 namespace debug {
 
-extern seastar::sharded<replica::database>* the_database;
+extern seastar::sharded<replica::database>* volatile the_database;
 
 
 }