From 941e6b7320daa0b08ffa66949eff994787ead210 Mon Sep 17 00:00:00 2001
From: Rene Cannao <rene@proxysql.com>
Date: Fri, 13 Feb 2026 17:24:55 +0000
Subject: [PATCH] Fix filters_rwlock initialization race condition

Add static initialization PTHREAD_RWLOCK_INITIALIZER to filters_rwlock
in debug.cpp to prevent race condition where proxy_debug() is called
before init_debug_struct() initializes the rwlock.

This fixes Valgrind errors in filter_debug_entry() where threads were
accessing an uninitialized rwlock.
---
 lib/debug.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/debug.cpp b/lib/debug.cpp
index 35fc52866..cebcd0048 100644
--- a/lib/debug.cpp
+++ b/lib/debug.cpp
@@ -18,7 +18,7 @@ using std::unordered_map;
 
 __thread unsigned long long pretime=0;
 static pthread_mutex_t debug_mutex;
-static pthread_rwlock_t filters_rwlock;
+static pthread_rwlock_t filters_rwlock = PTHREAD_RWLOCK_INITIALIZER;
 static SQLite3DB * debugdb_disk = NULL;
 sqlite3_stmt *statement1=NULL;
 static stmt_unique_ptr statement1_unique {};