Improve padding hole issues in QAbstractPrintDialogPrivate

Placing a boolean between two pointers means we'll have a 7-byte padding
hole (64-bit). So move it to the bottom of the class, consuming the tail
padding that needs to be there anyway on 64-bit systems.

On 32-bit Unix systems, the better place would be at the top, as the
parent class (QDialogPrivate) has a 3-byte tail padding. But that's
fragile, as QDialogPrivate can change, doesn't apply to MSVC's ABI and
doesn't gain us anything on 64-bit.

Change-Id: I3840d727dee443318644fffd1528e4f05f4142bd
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

1 files changed, 4 insertions, 3 deletions

diff --git a/src/printsupport/dialogs/qabstractprintdialog_p.h b/src/printsupport/dialogs/qabstractprintdialog_p.h
index a17a28f564..b646b74f34 100644
--- a/src/printsupport/dialogs/qabstractprintdialog_p.h
+++ b/src/printsupport/dialogs/qabstractprintdialog_p.h
@@ -69,16 +69,15 @@ class QAbstractPrintDialogPrivate : public QDialogPrivate
 
 public:
     QAbstractPrintDialogPrivate()
-        : printer(nullptr), pd(nullptr), ownsPrinter(false)
+        : printer(nullptr), pd(nullptr)
         , options(QAbstractPrintDialog::PrintToFile | QAbstractPrintDialog::PrintPageRange |
                 QAbstractPrintDialog::PrintCollateCopies | QAbstractPrintDialog::PrintShowPageSize),
-          minPage(0), maxPage(INT_MAX)
+          minPage(0), maxPage(INT_MAX), ownsPrinter(false)
     {
     }
 
     QPrinter *printer;
     QPrinterPrivate *pd;
-    bool ownsPrinter;
     QPointer<QObject> receiverToDisconnectOnClose;
     QByteArray memberToDisconnectOnClose;
 
@@ -88,6 +87,8 @@ public:
     void setPrinter(QPrinter *newPrinter);
     int minPage;
     int maxPage;
+
+    bool ownsPrinter;
 };
 
 QT_END_NAMESPACE