diff --git a/src/corelib/ipc/qsharedmemory.cpp b/src/corelib/ipc/qsharedmemory.cpp
index e9a57c6cec..dea41c798e 100644
--- a/src/corelib/ipc/qsharedmemory.cpp
+++ b/src/corelib/ipc/qsharedmemory.cpp
@@ -670,7 +670,8 @@ void QSharedMemoryPrivate::setUnixErrorString(QLatin1StringView function)
         error = QSharedMemory::OutOfResources;
         break;
     default:
-        errorString = QSharedMemory::tr("%1: unknown error %2").arg(function).arg(errno);
+        errorString = QSharedMemory::tr("%1: unknown error: %2")
+                .arg(function, qt_error_string(errno));
         error = QSharedMemory::UnknownError;
 #if defined QSHAREDMEMORY_DEBUG
         qDebug() << errorString << "key" << key << "errno" << errno << EINVAL;
diff --git a/src/corelib/ipc/qsharedmemory_win.cpp b/src/corelib/ipc/qsharedmemory_win.cpp
index 0cb32296ec..593c312f47 100644
--- a/src/corelib/ipc/qsharedmemory_win.cpp
+++ b/src/corelib/ipc/qsharedmemory_win.cpp
@@ -41,7 +41,8 @@ void QSharedMemoryPrivate::setWindowsErrorString(QLatin1StringView function)
         errorString = QSharedMemory::tr("%1: permission denied").arg(function);
         break;
     default:
-        errorString = QSharedMemory::tr("%1: unknown error %2").arg(function).arg(windowsError);
+        errorString = QSharedMemory::tr("%1: unknown error: %2")
+                .arg(function, qt_error_string(windowsError));
         error = QSharedMemory::UnknownError;
 #if defined QSHAREDMEMORY_DEBUG
         qDebug() << errorString << "key" << key;
diff --git a/src/corelib/ipc/qsystemsemaphore.cpp b/src/corelib/ipc/qsystemsemaphore.cpp
index 3f9a7018da..9b42b93995 100644
--- a/src/corelib/ipc/qsystemsemaphore.cpp
+++ b/src/corelib/ipc/qsystemsemaphore.cpp
@@ -351,7 +351,8 @@ void QSystemSemaphorePrivate::setUnixErrorString(QLatin1StringView function)
         error = QSystemSemaphore::KeyError;
         break;
     default:
-        errorString = QSystemSemaphore::tr("%1: unknown error %2").arg(function).arg(errno);
+        errorString = QSystemSemaphore::tr("%1: unknown error: %2")
+                .arg(function, qt_error_string(errno));
         error = QSystemSemaphore::UnknownError;
 #if defined QSYSTEMSEMAPHORE_DEBUG
         qDebug() << errorString << "key" << key << "errno" << errno << EINVAL;
diff --git a/src/corelib/ipc/qsystemsemaphore_win.cpp b/src/corelib/ipc/qsystemsemaphore_win.cpp
index 3d04694461..13da3f301c 100644
--- a/src/corelib/ipc/qsystemsemaphore_win.cpp
+++ b/src/corelib/ipc/qsystemsemaphore_win.cpp
@@ -30,7 +30,8 @@ void QSystemSemaphorePrivate::setWindowsErrorString(QLatin1StringView function)
         errorString = QCoreApplication::translate("QSystemSemaphore", "%1: permission denied").arg(function);
         break;
     default:
-        errorString = QCoreApplication::translate("QSystemSemaphore", "%1: unknown error %2").arg(function).arg(windowsError);
+        errorString = QCoreApplication::translate("QSystemSemaphore", "%1: unknown error: %2")
+                .arg(function, qt_error_string(windowsError));
         error = QSystemSemaphore::UnknownError;
 #if defined QSYSTEMSEMAPHORE_DEBUG
         qDebug() << errorString << "key" << key;