From 1a6e1660b175ba1c5c203746daeae03734e40a87 Mon Sep 17 00:00:00 2001
From: Marc Mutz <marc.mutz@qt.io>
Date: Wed, 21 Jun 2023 15:00:43 +0200
Subject: [PATCH] QWeakPointer: mark lock() [[nodiscard]]

The lock() function, added for std::weak_ptr compatibility, sounds
like QMutex::lock(), but is, in fact, a const function. QUIP-0019 says
such functions must be marked [[nodiscard]]. For symmetry, also mark
toStrongRef() and toWeakRef() as [[nodiscard]].

Change-Id: Ifb6e447d2cd96fedd9a78decdfac6bc57c1d282a
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
(cherry picked from commit 81d357ff8a7af8704ba5657caef04f28e7099625)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
---
 src/corelib/tools/qsharedpointer_impl.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/corelib/tools/qsharedpointer_impl.h b/src/corelib/tools/qsharedpointer_impl.h
index dd6bd22fca8..ac9bd2d77eb 100644
--- a/src/corelib/tools/qsharedpointer_impl.h
+++ b/src/corelib/tools/qsharedpointer_impl.h
@@ -383,7 +383,7 @@ public:
 
     inline void clear() { QSharedPointer copy; swap(copy); }
 
-    QWeakPointer<T> toWeakRef() const;
+    [[nodiscard]] QWeakPointer<T> toWeakRef() const;
 
     template <typename... Args>
     static QSharedPointer create(Args && ...arguments)
@@ -615,9 +615,9 @@ public:
 
     inline void clear() { *this = QWeakPointer(); }
 
-    inline QSharedPointer<T> toStrongRef() const { return QSharedPointer<T>(*this); }
+    [[nodiscard]] QSharedPointer<T> toStrongRef() const { return QSharedPointer<T>(*this); }
     // std::weak_ptr compatibility:
-    inline QSharedPointer<T> lock() const { return toStrongRef(); }
+    [[nodiscard]] QSharedPointer<T> lock() const { return toStrongRef(); }
 
     template <class X>
     bool operator==(const QWeakPointer<X> &o) const noexcept