diff --git a/src/corelib/io/qfile.h b/src/corelib/io/qfile.h
index 1153ba76869..839a2b51fee 100644
--- a/src/corelib/io/qfile.h
+++ b/src/corelib/io/qfile.h
@@ -37,7 +37,7 @@ Q_CORE_EXPORT bool qEnableNtfsPermissionChecks() noexcept;
 Q_CORE_EXPORT bool qDisableNtfsPermissionChecks() noexcept;
 Q_CORE_EXPORT bool qAreNtfsPermissionChecksEnabled() noexcept;
 
-class [[nodiscard]] QNtfsPermissionCheckGuard
+class QNtfsPermissionCheckGuard
 {
     Q_DISABLE_COPY_MOVE(QNtfsPermissionCheckGuard)
 public:
diff --git a/src/corelib/kernel/qobject.h b/src/corelib/kernel/qobject.h
index 3d1c102fc59..88ba5318a1a 100644
--- a/src/corelib/kernel/qobject.h
+++ b/src/corelib/kernel/qobject.h
@@ -439,7 +439,7 @@ inline QBindingStorage *qGetBindingStorage(QObject *o)
 Q_CORE_EXPORT QDebug operator<<(QDebug, const QObject *);
 #endif
 
-class [[nodiscard]] QSignalBlocker
+class QSignalBlocker
 {
 public:
     Q_NODISCARD_CTOR
diff --git a/src/corelib/kernel/qproperty.h b/src/corelib/kernel/qproperty.h
index 3ed977d16ee..070907c6080 100644
--- a/src/corelib/kernel/qproperty.h
+++ b/src/corelib/kernel/qproperty.h
@@ -53,7 +53,7 @@ Q_CORE_EXPORT void beginPropertyUpdateGroup();
 Q_CORE_EXPORT void endPropertyUpdateGroup();
 }
 
-class [[nodiscard]] QScopedPropertyUpdateGroup
+class QScopedPropertyUpdateGroup
 {
     Q_DISABLE_COPY_MOVE(QScopedPropertyUpdateGroup)
 public:
@@ -287,7 +287,7 @@ private:
 };
 
 template <typename Functor>
-class [[nodiscard]] QPropertyChangeHandler : public QPropertyObserver
+class QPropertyChangeHandler : public QPropertyObserver
 {
     Functor m_handler;
 public:
@@ -314,7 +314,7 @@ public:
     }
 };
 
-class [[nodiscard]] QPropertyNotifier : public QPropertyObserver
+class QPropertyNotifier : public QPropertyObserver
 {
     std::function<void()> m_handler;
 public:
diff --git a/src/corelib/kernel/qproperty_p.h b/src/corelib/kernel/qproperty_p.h
index 9946482d7f1..277767b3c07 100644
--- a/src/corelib/kernel/qproperty_p.h
+++ b/src/corelib/kernel/qproperty_p.h
@@ -94,7 +94,7 @@ struct QPropertyBindingDataPointer
     }
 };
 
-struct [[nodiscard]] QPropertyObserverNodeProtector
+struct QPropertyObserverNodeProtector
 {
     Q_DISABLE_COPY_MOVE(QPropertyObserverNodeProtector)
 
diff --git a/src/corelib/thread/qmutex.h b/src/corelib/thread/qmutex.h
index 7a6bd1a3ba7..496d0ea5029 100644
--- a/src/corelib/thread/qmutex.h
+++ b/src/corelib/thread/qmutex.h
@@ -216,7 +216,7 @@ bool QRecursiveMutex::tryLock(int timeout) QT_MUTEX_LOCK_NOEXCEPT
 #endif
 
 template <typename Mutex>
-class [[nodiscard]] QMutexLocker
+class QMutexLocker
 {
 public:
     Q_NODISCARD_CTOR
@@ -313,7 +313,7 @@ private:
 class QRecursiveMutex : public QMutex {};
 
 template <typename Mutex>
-class [[nodiscard]] QMutexLocker
+class QMutexLocker
 {
 public:
     Q_NODISCARD_CTOR
diff --git a/src/corelib/thread/qorderedmutexlocker_p.h b/src/corelib/thread/qorderedmutexlocker_p.h
index 43985a3faa3..fb2e223e01a 100644
--- a/src/corelib/thread/qorderedmutexlocker_p.h
+++ b/src/corelib/thread/qorderedmutexlocker_p.h
@@ -28,7 +28,7 @@ QT_BEGIN_NAMESPACE
   Locks 2 mutexes in a defined order, avoiding a recursive lock if
   we're trying to lock the same mutex twice.
 */
-class [[nodiscard]] QOrderedMutexLocker
+class QOrderedMutexLocker
 {
 public:
     Q_NODISCARD_CTOR
@@ -120,7 +120,7 @@ private:
 
 #else
 
-class [[nodiscard]] QOrderedMutexLocker
+class QOrderedMutexLocker
 {
 public:
     Q_DISABLE_COPY(QOrderedMutexLocker)
diff --git a/src/corelib/thread/qsemaphore.h b/src/corelib/thread/qsemaphore.h
index 0b9db83471b..28f3f626649 100644
--- a/src/corelib/thread/qsemaphore.h
+++ b/src/corelib/thread/qsemaphore.h
@@ -61,7 +61,7 @@ bool QSemaphore::tryAcquire(int n, int timeout)
 }
 #endif
 
-class [[nodiscard]] QSemaphoreReleaser
+class QSemaphoreReleaser
 {
 public:
     Q_NODISCARD_CTOR
diff --git a/src/corelib/tools/qatomicscopedvaluerollback_p.h b/src/corelib/tools/qatomicscopedvaluerollback_p.h
index e70889c288d..67299327fcd 100644
--- a/src/corelib/tools/qatomicscopedvaluerollback_p.h
+++ b/src/corelib/tools/qatomicscopedvaluerollback_p.h
@@ -23,7 +23,7 @@
 QT_BEGIN_NAMESPACE
 
 template <typename T>
-class [[nodiscard]] QAtomicScopedValueRollback
+class QAtomicScopedValueRollback
 {
     std::atomic<T> &m_atomic;
     T m_value;
diff --git a/src/corelib/tools/qscopedvaluerollback.h b/src/corelib/tools/qscopedvaluerollback.h
index 6e724886f4a..0ae3efd0c0f 100644
--- a/src/corelib/tools/qscopedvaluerollback.h
+++ b/src/corelib/tools/qscopedvaluerollback.h
@@ -9,7 +9,7 @@
 QT_BEGIN_NAMESPACE
 
 template <typename T>
-class [[nodiscard]] QScopedValueRollback
+class QScopedValueRollback
 {
 public:
     Q_NODISCARD_CTOR
diff --git a/src/corelib/tools/qscopeguard.h b/src/corelib/tools/qscopeguard.h
index 0d756ebbd9f..9be6634cc87 100644
--- a/src/corelib/tools/qscopeguard.h
+++ b/src/corelib/tools/qscopeguard.h
@@ -13,7 +13,7 @@
 QT_BEGIN_NAMESPACE
 
 template <typename F>
-class [[nodiscard]] QScopeGuard
+class QScopeGuard
 {
 public:
     Q_NODISCARD_CTOR