Fix invalid QApplication construction

QApplication construction with argc=0 is incorrect according to the doc.
The construction pattern is furthermore causing problems in QtWebEngine,
which is expecting the executable name as first command-line arguments
as reported in QTBUG-110157.

Fix problem by using the Microsoft-specific __argc and __argv globals.
This ensures that the actual command-line arguments are used for
QApplication construction.

Pick-to: 6.5
Task-number: QTBUG-110158
Change-Id: Ib8e6ac7a1c24cfabfdafe8489fe8b8c4765753fd
Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>

2 files changed, 3 insertions, 6 deletions

diff --git a/src/activeqt/control/qaxserver.cpp b/src/activeqt/control/qaxserver.cpp
index d7ea1d2..aa4b951 100644
--- a/src/activeqt/control/qaxserver.cpp
+++ b/src/activeqt/control/qaxserver.cpp
@@ -438,8 +438,7 @@ HRESULT UpdateRegistry(bool bRegister, bool perUser)
     // we try to create the ActiveX widgets later on...
     bool delete_qApp = false;
     if (!qApp) {
-        static int argc = 0; // static lifetime, since it's passed as reference to QApplication, which has a lifetime exceeding the stack frame
-        (void)new QApplication(argc, nullptr);
+        (void)new QApplication(__argc, __argv);
         delete_qApp = true;
     }
 
@@ -1145,8 +1144,7 @@ extern "C" HRESULT __stdcall DumpIDL(const QString &outfile, const QString &ver)
     // dummy application to create widgets
     bool delete_qApp = false;
     if (!qApp) {
-        static int argc = 0; // static lifetime, since it's passed as reference to QApplication, which has a lifetime exceeding the stack frame
-        (void)new QApplication(argc, nullptr);
+        (void)new QApplication(__argc, __argv);
         delete_qApp = true;
     }
 
diff --git a/src/activeqt/control/qaxserverbase.cpp b/src/activeqt/control/qaxserverbase.cpp
index ac52583..0800cd9 100644
--- a/src/activeqt/control/qaxserverbase.cpp
+++ b/src/activeqt/control/qaxserverbase.cpp
@@ -882,8 +882,7 @@ HRESULT QClassFactory::CreateInstanceHelper(IUnknown *pUnkOuter, REFIID iid, voi
     // Make sure a QApplication instance is present (inprocess case)
     if (!qApp) {
         qax_ownQApp = true;
-        static int argc = 0; // static lifetime, since it's passed as reference to QApplication, which has a lifetime exceeding the stack frame
-        new QApplication(argc, nullptr);
+        new QApplication(__argc, __argv);
     }
     QGuiApplication::setQuitOnLastWindowClosed(false);