From 1c6828b9d61a5988e91e67342cc0f616fa87949e Mon Sep 17 00:00:00 2001
From: Marc Mutz <marc.mutz@kdab.com>
Date: Wed, 26 Jun 2019 07:24:18 +0200
Subject: QFreeList: fix memory order on block deletion
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Blocks are likely to have been created in a differnt thread from the one
performing their deletion, so we need an acquire fence.

The rest of the atomics use in the class looks ok, but nevertheless warrants
a deeper analysis.

Change-Id: I1571ded3a06695b0d58b5bf1d80d6283ac21f959
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
(cherry picked from commit 6fa34930c23c7494a3f2703777f46794ff091e2b)
(cherry picked from commit 51bcc7e07e2bb5b42bb200dcd5269e9e9e2fe240)
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
---
 src/corelib/tools/qfreelist_p.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/corelib/tools/qfreelist_p.h b/src/corelib/tools/qfreelist_p.h
index 2f98cf5cc1..665b651e69 100644
--- a/src/corelib/tools/qfreelist_p.h
+++ b/src/corelib/tools/qfreelist_p.h
@@ -218,7 +218,7 @@ template <typename T, typename ConstantsType>
 inline QFreeList<T, ConstantsType>::~QFreeList()
 {
     for (int i = 0; i < ConstantsType::BlockCount; ++i)
-        delete [] _v[i].load();
+        delete [] _v[i].loadAcquire();
 }
 
 template <typename T, typename ConstantsType>
-- 
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