Hi,
I am just new to Qt programming and try to use both Qwt (6.1.1) and Qwtpolar (1.1.1) libs on windows XP under Qt5.2.1 (mingw48_32)
On the hereafter example, the release version works properly but I can't make the debug version work.
I've got the following message : "Qwidget: Must construct a QApplication before a QWidget"
I've checked with the debugger that it fails when it tries to create the QwtPolarPlot instance.
As the objects files are created within the ./debug directrory I know that the CONFIG test works fine
and I properly refer to the debug libraries versions -- qwtd and qwtpolard --
moreover, there are also properly referred in the Makefile.debug
These libs were created with their default .pro files within QtCreator.

Any idea ?


The .cpp file

MainWindow::MainWindow( QWidget *parent ):
QMainWindow( parent )
{
m_pCentralWidget = new QWidget(this);
setCentralWidget(m_pCentralWidget);

m_pPolarGraph = new QwtPolarPlot(m_pCentralWidget);
QGridLayout *pLayout = new QGridLayout(m_pCentralWidget);
pLayout->addWidget(m_pPolarGraph, 1, 0);
}


int main( int argc, char **argv )
{
QApplication a( argc, argv );
MainWindow mainWindow;
mainWindow.show();
return a.exec();
}



The .Pro file

TARGET = trial1
QT += widgets
MOC_DIR = moc
DEFINES += QWT_DLL QWT_POLAR_DLL

QWT_ROOT = C:\LocalApplications\qwt-6.1.1
QWT_LIBS = -L$${QWT_ROOT}\lib
QWT_INCLUDES = $${QWT_ROOT}\src

QWT_POLAR_ROOT = C:\LocalApplications\qwtpolar-1.1.1
QWT_POLAR_LIBS = -L$${QWT_POLAR_ROOT}\lib
QWT_POLAR_INCLUDES = $${QWT_POLAR_ROOT}\src

INCLUDEPATH += $${QWT_POLAR_INCLUDES} $${QWT_INCLUDES}
LIBS += $${QWT_LIBS} $${QWT_POLAR_LIBS}

CONFIG(debug, debug|release) {
DESTDIR = ./debug
LIBS += -lqwtd -lqwtpolard
OBJECTS_DIR =./debug
} else {
DESTDIR = ./release
LIBS += -lqwt -lqwtpolar
OBJECTS_DIR =./release
}

SOURCES += \
main.cpp