Build fixes for GCC 11

Task-number: QTBUG-89977
Change-Id: Ic1b7ddbffb8a0a00f8c621d09a868f1d94a52c21
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/text/qanystringview.h

@@ -45,6 +45,7 @@
 #ifdef __cpp_impl_three_way_comparison
 #include <compare>
 #endif
+#include <limits>
 
 QT_BEGIN_NAMESPACE
 

src/corelib/text/qbytearraymatcher.h

@@ -42,6 +42,8 @@
 
 #include <QtCore/qbytearray.h>
 
+#include <limits>
+
 QT_BEGIN_NAMESPACE
 
 

src/corelib/tools/qsharedpointer_impl.h

@@ -152,9 +152,6 @@ namespace QtSharedPointer {
 #endif
         inline void checkQObjectShared(...) { }
         inline void setQObjectShared(...) { }
-
-        inline void operator delete(void *ptr) { ::operator delete(ptr); }
-        inline void operator delete(void *, void *) { }
     };
     // sizeof(ExternalRefCountData) = 12 (32-bit) / 16 (64-bit)
 

src/plugins/platforms/xcb/qxcbwindow.cpp

@@ -682,7 +682,7 @@ void QXcbWindow::show()
         if (isTransient(window())) {
             const QWindow *tp = window()->transientParent();
             if (tp && tp->handle())
-                transientXcbParent = static_cast<const QXcbWindow *>(tp->handle())->winId();
+                transientXcbParent = tp->handle()->winId();
             // Default to client leader if there is no transient parent, else modal dialogs can
             // be hidden by their parents.
             if (!transientXcbParent)