From bf29a4d7464ec587e8a6a566d495ac4636327d0d Mon Sep 17 00:00:00 2001
From: Yannis Guyon <yguyon@google.com>
Date: Fri, 27 Jan 2023 13:02:46 +0100
Subject: [PATCH] Avoid double-checked locking with TSAN in parallel

Omit the first check of the double-checked locking pattern in
recordException() in parallel.cpp when CV_THREAD_SANITIZER is defined.
This should only slow recordException() down when the thread sanitizer
is used, and avoids the TSAN data race warning.
---
 modules/core/src/parallel.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/modules/core/src/parallel.cpp b/modules/core/src/parallel.cpp
index a4a7baf0f6..efecefc4b4 100644
--- a/modules/core/src/parallel.cpp
+++ b/modules/core/src/parallel.cpp
@@ -263,7 +263,9 @@ namespace {
         void recordException(const cv::String& msg)
 #endif
         {
+#ifndef CV_THREAD_SANITIZER
             if (!hasException)
+#endif
             {
                 cv::AutoLock lock(cv::getInitializationMutex());
                 if (!hasException)