6 files changed, 22 insertions, 46 deletions
diff --git a/src/corelib/kernel/qcore_mac.mm b/src/corelib/kernel/qcore_mac.mm
index e774cebcbf..99ad4ce666 100644
--- a/src/corelib/kernel/qcore_mac.mm
+++ b/src/corelib/kernel/qcore_mac.mm
@@ -117,7 +117,7 @@ bool AppleUnifiedLogger::messageHandler(QtMsgType msgType, const QMessageLogCont
 
     const bool isDefault = !context.category || !strcmp(context.category, "default");
     os_log_t log = isDefault ? OS_LOG_DEFAULT :
-        cachedLog(subsystem, QString::fromLatin1(context.category));
+        os_log_create(subsystem.toLatin1().constData(), context.category);
     os_log_type_t logType = logTypeForMessageType(msgType);
 
     if (!os_log_type_enabled(log, logType))
@@ -153,29 +153,6 @@ os_log_type_t AppleUnifiedLogger::logTypeForMessageType(QtMsgType msgType)
     return OS_LOG_TYPE_DEFAULT;
 }
 
-os_log_t AppleUnifiedLogger::cachedLog(const QString &subsystem, const QString &category)
-{
-    static QBasicMutex mutex;
-    const auto locker = qt_scoped_lock(mutex);
-
-    static QHash<QPair<QString, QString>, os_log_t> logs;
-    const auto cacheKey = qMakePair(subsystem, category);
-    os_log_t log = logs.value(cacheKey);
-
-    if (!log) {
-        log = os_log_create(subsystem.toLatin1().constData(),
-            category.toLatin1().constData());
-        logs.insert(cacheKey, log);
-
-        // Technically we should release the os_log_t resource when done
-        // with it, but since we don't know when a category is disabled
-        // we keep all cached os_log_t instances until shutdown, where
-        // the OS will clean them up for us.
-    }
-
-    return log;
-}
-
 #endif // QT_USE_APPLE_UNIFIED_LOGGING
 
 // -------------------------------------------------------------------------
diff --git a/src/corelib/kernel/qelapsedtimer.cpp b/src/corelib/kernel/qelapsedtimer.cpp
index 3bfb1f15ec..230bcac33f 100644
--- a/src/corelib/kernel/qelapsedtimer.cpp
+++ b/src/corelib/kernel/qelapsedtimer.cpp
@@ -111,18 +111,6 @@ QT_BEGIN_NAMESPACE
     that the clock used is the same as QElapsedTimer (see
     QElapsedTimer::clockType()).
 
-    \section2 32-bit overflows
-
-    Some of the clocks used by QElapsedTimer have a limited range and may
-    overflow after hitting the upper limit (usually 32-bit). QElapsedTimer
-    deals with this overflow issue and presents a consistent timing. However,
-    when extracting the time since reference from QElapsedTimer, two
-    different processes in the same machine may have different understanding
-    of how much time has actually elapsed.
-
-    The information on which clocks types may overflow and how to remedy that
-    issue is documented along with the clock types.
-
     \sa QTime, QTimer, QDeadlineTimer
 */
 
@@ -138,10 +126,13 @@ QT_BEGIN_NAMESPACE
     used.
 
     \value SystemTime         The human-readable system time. This clock is not monotonic.
-    \value MonotonicClock     The system's monotonic clock, usually found in Unix systems. This clock is monotonic and does not overflow.
+    \value MonotonicClock     The system's monotonic clock, usually found in Unix systems.
+                              This clock is monotonic.
     \value TickCounter        Not used anymore.
-    \value MachAbsoluteTime   The Mach kernel's absolute time (\macos and iOS). This clock is monotonic and does not overflow.
-    \value PerformanceCounter The performance counter provided by Windows. This clock is monotonic and does not overflow.
+    \value MachAbsoluteTime   The Mach kernel's absolute time (\macos and iOS).
+                              This clock is monotonic.
+    \value PerformanceCounter The performance counter provided by Windows.
+                              This clock is monotonic.
 
     \section2 SystemTime
 
@@ -159,8 +150,6 @@ QT_BEGIN_NAMESPACE
     arbitrary point in the past. This clock type is used on Unix systems
     which support POSIX monotonic clocks (\tt{_POSIX_MONOTONIC_CLOCK}).
 
-    This clock does not overflow.
-
     \section2 MachAbsoluteTime
 
     This clock type is based on the absolute time presented by Mach kernels,
@@ -169,14 +158,14 @@ QT_BEGIN_NAMESPACE
     a POSIX monotonic clock with values differing from the Mach absolute
     time.
 
-    This clock is monotonic and does not overflow.
+    This clock is monotonic.
 
     \section2 PerformanceCounter
 
     This clock uses the Windows functions \tt{QueryPerformanceCounter} and
     \tt{QueryPerformanceFrequency} to access the system's performance counter.
 
-    This clock is monotonic and does not overflow.
+    This clock is monotonic.
 
     \sa clockType(), isMonotonic()
 */
diff --git a/src/corelib/kernel/qobject.cpp b/src/corelib/kernel/qobject.cpp
index 1eb79138d9..d57bcc31cc 100644
--- a/src/corelib/kernel/qobject.cpp
+++ b/src/corelib/kernel/qobject.cpp
@@ -2460,6 +2460,7 @@ static bool check_method_code(int code, const QObject *object,
     return true;
 }
 
+Q_DECL_COLD_FUNCTION
 static void err_method_notfound(const QObject *object,
                                 const char *method, const char *func)
 {
@@ -2481,6 +2482,7 @@ static void err_method_notfound(const QObject *object,
 }
 
 
+Q_DECL_COLD_FUNCTION
 static void err_info_about_objects(const char * func,
                                     const QObject * sender,
                                     const QObject * receiver)
diff --git a/src/corelib/kernel/qsharedmemory_p.h b/src/corelib/kernel/qsharedmemory_p.h
index e6e989abda..0c13375094 100644
--- a/src/corelib/kernel/qsharedmemory_p.h
+++ b/src/corelib/kernel/qsharedmemory_p.h
@@ -56,14 +56,20 @@
 #include <QtCore/qstring.h>
 
 #ifdef QT_NO_SHAREDMEMORY
-# ifndef QT_NO_SYSTEMSEMAPHORE
+#    ifndef QT_NO_SYSTEMSEMAPHORE
+
+QT_BEGIN_NAMESPACE
+
 namespace QSharedMemoryPrivate
 {
     int createUnixKeyFile(const QString &fileName);
     QString makePlatformSafeKey(const QString &key,
             const QString &prefix = QLatin1String("qipc_sharedmemory_"));
 }
-#endif
+
+QT_END_NAMESPACE
+
+#    endif
 #else
 
 #include "qsystemsemaphore.h"
diff --git a/src/corelib/kernel/qsharedmemory_systemv.cpp b/src/corelib/kernel/qsharedmemory_systemv.cpp
index 0ba5f65641..b9adb4300c 100644
--- a/src/corelib/kernel/qsharedmemory_systemv.cpp
+++ b/src/corelib/kernel/qsharedmemory_systemv.cpp
@@ -109,7 +109,7 @@ key_t QSharedMemoryPrivate::handle()
      0 already existed
      1 created
   */
-int QSharedMemoryPrivate::createUnixKeyFile(const QString &fileName)
+int QT_PREPEND_NAMESPACE(QSharedMemoryPrivate)::createUnixKeyFile(const QString &fileName)
 {
     int fd = qt_safe_open(QFile::encodeName(fileName).constData(),
             O_EXCL | O_CREAT | O_RDWR, 0640);
diff --git a/src/corelib/kernel/qtimer.cpp b/src/corelib/kernel/qtimer.cpp
index 25ce0c032f..79c7b2628c 100644
--- a/src/corelib/kernel/qtimer.cpp
+++ b/src/corelib/kernel/qtimer.cpp
@@ -222,6 +222,8 @@ void QTimer::start()
 
     If \l singleShot is true, the timer will be activated only once.
 
+    \note   Keeping the event loop busy with a zero-timer is bound to
+            cause trouble and highly erratic behavior of the UI.
 */
 void QTimer::start(int msec)
 {