From 1dedeb37bf23689c9ac38ba4a214440a0e94291e Mon Sep 17 00:00:00 2001
From: Nekotekina <nekotekina@gmail.com>
Date: Wed, 5 Jun 2019 15:51:25 +0300
Subject: [PATCH] Fix lf_queue_base::wait

Add missing state change
---
 Utilities/cond.cpp | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Utilities/cond.cpp b/Utilities/cond.cpp
index 2e1a900a05..718ce5cb30 100644
--- a/Utilities/cond.cpp
+++ b/Utilities/cond.cpp
@@ -275,6 +275,14 @@ void shared_cond::imp_notify() noexcept
 
 bool lf_queue_base::wait(u64 _timeout)
 {
+	auto _old = m_head.compare_and_swap(0, 1);
+
+	if (_old)
+	{
+		verify("lf_queue concurrent wait" HERE), _old != 1;
+		return true;
+	}
+
 	return balanced_wait_until(m_head, _timeout, [](std::uintptr_t& head, auto... ret) -> int
 	{
 		if (head != 1)