From ac328eec8d227958961ca29379ff0b869435aedc Mon Sep 17 00:00:00 2001
From: Marc Mutz <marc.mutz@qt.io>
Date: Fri, 7 Jul 2023 07:48:40 +0200
Subject: [PATCH] QAtomicScopedValueRollback: fix CTAD for
 Q(Basic)AtomicPointer
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We need deduction guides to turn the AtomicPointer template argument
(the pointee) into a pointer:

    QAtomicPointer<int> → QAtomicScopedValueRollback<int*>

Extend a test to cover pointers, too.

Fixes: QTBUG-115105
Change-Id: Ib416c6a43e4da480b707a0bf6a10d186bbaad163
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
(cherry picked from commit 97ec1d7d8ecb07be20cf43f475067faba04f5aa5)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
---
 src/corelib/tools/qatomicscopedvaluerollback_p.h           | 7 +++++++
 .../tst_qatomicscopedvaluerollback.cpp                     | 7 +++++++
 2 files changed, 14 insertions(+)

diff --git a/src/corelib/tools/qatomicscopedvaluerollback_p.h b/src/corelib/tools/qatomicscopedvaluerollback_p.h
index 67299327fcd..a5c1a2fa611 100644
--- a/src/corelib/tools/qatomicscopedvaluerollback_p.h
+++ b/src/corelib/tools/qatomicscopedvaluerollback_p.h
@@ -108,6 +108,13 @@ public:
     }
 };
 
+template <typename T>
+QAtomicScopedValueRollback(QBasicAtomicPointer<T> &)
+    -> QAtomicScopedValueRollback<T*>;
+template <typename T>
+QAtomicScopedValueRollback(QBasicAtomicPointer<T> &, std::memory_order)
+    -> QAtomicScopedValueRollback<T*>;
+
 QT_END_NAMESPACE
 
 #endif // QATOMICASCOPEDVALUEROLLBACK_P_H
diff --git a/tests/auto/corelib/tools/qatomicscopedvaluerollback/tst_qatomicscopedvaluerollback.cpp b/tests/auto/corelib/tools/qatomicscopedvaluerollback/tst_qatomicscopedvaluerollback.cpp
index 81d8242f71a..8a56d957bd2 100644
--- a/tests/auto/corelib/tools/qatomicscopedvaluerollback/tst_qatomicscopedvaluerollback.cpp
+++ b/tests/auto/corelib/tools/qatomicscopedvaluerollback/tst_qatomicscopedvaluerollback.cpp
@@ -24,23 +24,30 @@ void tst_QAtomicScopedValueRollback::leavingScope()
     QAtomicInt i = 0;
     QBasicAtomicInteger<bool> b = false;
     std::atomic<bool> b2 = false;
+    int x = 0, y = 42;
+    QBasicAtomicPointer<int> p = &x;
 
     //test rollback on going out of scope
     {
         QAtomicScopedValueRollback ri(i);
         QAtomicScopedValueRollback rb(b);
         QAtomicScopedValueRollback rb2(b2, true);
+        QAtomicScopedValueRollback rp(p);
         QCOMPARE(b.loadRelaxed(), false);
         QCOMPARE(b2, true);
         QCOMPARE(i.loadRelaxed(), 0);
+        QCOMPARE(p.loadRelaxed(), &x);
         b.storeRelaxed(true);
         i.storeRelaxed(1);
+        p.storeRelaxed(&y);
         QCOMPARE(b.loadRelaxed(), true);
         QCOMPARE(i.loadRelaxed(), 1);
+        QCOMPARE(p.loadRelaxed(), &y);
     }
     QCOMPARE(b.loadRelaxed(), false);
     QCOMPARE(b2, false);
     QCOMPARE(i.loadRelaxed(), 0);
+    QCOMPARE(p.loadRelaxed(), &x);
 }
 
 void tst_QAtomicScopedValueRollback::leavingScopeAfterCommit()