From: Ondřej Surý <ondrej@sury.org>
Date: Thu, 4 Jun 2026 09:58:12 +0000 (+0200)
Subject: Only update the global tid_count once
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a570e37c067fc83e5d78698a118e8c8e45085498;p=thirdparty%2Fbind9.git

Only update the global tid_count once

Normally, the tid_count is initialized only once at the beginning of the
application.  The only exception is the pattern in the unit test where
isc_loopmgr is repeatedly created and torn down and each creation of
isc_loopmgr_t calls isc__tid_initcount() with the previous value.

ThreadSanitizer sees that as write operation on unprotected memory are
reports this as data race even though the value has not really changed.

This has been fixed by skipping the tid_count value update on repeated
calls.
---

diff --git a/lib/isc/tid.c b/lib/isc/tid.c
index ce385abeb7f..9550908a220 100644
--- a/lib/isc/tid.c
+++ b/lib/isc/tid.c
@@ -11,7 +11,6 @@
  * information regarding copyright ownership.
  */
 
-#include <stdlib.h>
 #include <sys/types.h>
 #include <unistd.h>
 
@@ -45,7 +44,9 @@ void
 isc__tid_initcount(isc_tid_t count) {
 	REQUIRE(tid_count == 0 || tid_count == count);
 	REQUIRE(count < ISC_TID_MAX);
-	tid_count = count;
+	if (tid_count == 0) {
+		tid_count = count;
+	}
 }
 
 /**