Hello all,
Firstly I am running QtCreator 0.9.2 / with Qt 4.5.0, on Windows Vista Business.

I followed the install instructions for qwt; and also built the examples at time of install. Next I opened the pro file of the example (data_plot) through QtCreator and everything worked nicely. (Had to add C:\qt\qtcreator\qt\bin; C:\qt\qtcreator\mingw\bin; c:\qwt-5.1.1\bin to the PATH Variable.)

After spending some time trying to apply the same concepts as the example in my own simple QDialog, I ran into an error on both Run and Debug: "This application has requested the Runtime to terminate it in an unusual way. Please contact the application's support team for more information.", Titled: "Microsoft Visual C++ Runtime Library". The Application Output window of QT Creator displays:
"Starting e:/data/qt_creator_projects/bin/DriveCycle.exe..."
"Invalid parameter passed to C runtime function."
"Invalid parameter passed to C runtime function."
""
"e:/data/qt_creator_projects/bin/DriveCycle.exe exited with code 3".

Here are the files I am working with:

DriveCycle.pro
Qt Code: 
  1. include (E:/Data/Qt_Creator_Projects/qwtInclude.pri)
  2. TARGET = DriveCycle
  3. DESTDIR_TARGET = E:/Data/Qt_Creator_Projects/bin/DriveCycle
  4.  
  5. # TEMPLATE = app
  6. SOURCES = main.cpp \
  7.     plotterdialog.cpp
  8. HEADERS = plotterdialog.h
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main.cpp
Qt Code: 
  1. #include <QtGui/QApplication>
  2. #include "plotterdialog.h"
  3.  
  4. int main(int argc, char *argv[])
  5. {
  6.     QApplication a(argc, argv);
  7.     PlotterDialog w;
  8.     w.show();
  9.     return a.exec();
  10. }
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plotterdialog.cpp
Qt Code: 
  1. #include "plotterdialog.h"
  2. #include <QHBoxLayout>
  3. #include <qwt_plot.h>
  4. #include <qwt_plot_curve.h>
  5. #include <qwt_text.h>
  6.  
  7. PlotterDialog::PlotterDialog(QWidget *parent)
  8.     : QWidget(parent)
  9. {
  10.   lbl1 = new QLabel(tr("Good Morning"));
  11.   hbl1= new QHBoxLayout;
  12.   hbl1->addWidget(lbl1);
  13.   QwtText *txt1;
  14.   txt1 = new QwtText("Two Curves");
  15.   QwtPlot *myPlot;
  16.   double x[100], y1[100], y2[100];
  17.   myPlot = new QwtPlot(txt1->text(),parent);
  18.   //hbl1->addWidget(qPlot);
  19.   setLayout(hbl1);
  20.  
  21. }
  22.  
  23. PlotterDialog::~PlotterDialog()
  24. {
  25.  
  26. }
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plotterdialog.h
Qt Code: 
  1. #ifndef PLOTTERDIALOG_H
  2. #define PLOTTERDIALOG_H
  3.  
  4. #include <QtGui/QDialog>
  5. #include <QtGui>
  6.  
  7. #include "plotter.h"
  8. //#include <qwt_plot.h>
  9.  
  10. class QLabel;
  12. class PlotterDialog : public QWidget
  13. {
  14.     Q_OBJECT
  15.  
  16. public:
  17.     PlotterDialog(QWidget *parent = 0);
  18.     ~PlotterDialog();
  19.     QLabel* lbl1;
  20.     QHBoxLayout* hbl1;
  21.  
  22.  
  23. };
  24.  
  25. #endif // PLOTTERDIALOG_H
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qwtInclude.pri (included in DriveCycle.pro)
Qt Code: 
  1. QT_ROOT = C:/Qt/QtCreator/Qt
  2. QWT_ROOT = C:/qwt-5.1.1
  3. MINGW_ROOT = C:/Qt/QtCreator/mingw
  4. MyProjectRoot = E:/Data/QT_Creator_Projects/
  5.  
  6. SUFFIX_STR =
  7. VVERSION = $$[QT_VERSION]
  8. isEmpty(VVERSION) {
  9.  
  10.     # Qt 3
  11.     debug {
  12.         SUFFIX_STR = $${DEBUG_SUFFIX}
  13.     }
  14.     else {
  15.         SUFFIX_STR = $${RELEASE_SUFFIX}
  16.     }
  17. }
  18. else {
  19.     CONFIG(debug, debug|release) {
  20.         SUFFIX_STR = $${DEBUG_SUFFIX}
  21.     }
  22.     else {
  23.         SUFFIX_STR = $${RELEASE_SUFFIX}
  24.     }
  25. }
  26.  
  27. TEMPLATE     = app
  28.  
  29. MOC_DIR      = moc
  30. INCLUDEPATH += $${QWT_ROOT}/src\
  31.                 $${QWT_ROOT}/include/qwt5\
  32.                 $${QT_ROOT}/include\
  33.                 $${QT_ROOT}/bin\
  34.                 $${MINGW_ROOT}/include\
  35.                 $${MINGW_ROOT}/bin\
  36.                 $${MINGW_ROOT}/lib
  37.  
  38.  
  39. DEPENDPATH  += $${QWT_ROOT}/src
  40. OBJECTS_DIR  = obj$${SUFFIX_STR}
  41. DESTDIR      = $${MyProjectRoot}/bin/$${SUFFIX_STR}
  42. QMAKE_LIBDIR +=$${MINGW_ROOT}/lib
  43.  
  44. QWTLIB       = qwt$${SUFFIX_STR}
  45.  
  46. win32 {
  47.     contains(CONFIG, QwtDll) {
  48.         DEFINES    += QT_DLL QWT_DLL
  49.         QWTLIB = $${QWTLIB}$${VER_MAJ}
  50.     }
  51.  
  52.     win32-msvc:LIBS  += $${QWT_ROOT}/lib/$${QWTLIB}.lib
  53.     win32-msvc.net:LIBS  += $${QWT_ROOT}/lib/$${QWTLIB}.lib
  54.     win32-msvc2005:LIBS += $${QWT_ROOT}/lib/$${QWTLIB}.lib
  55.     win32-g++:LIBS   += -L$${QWT_ROOT}/lib -l$${QWTLIB}
  56. }
  57. else {
  58.     LIBS        += -L$${QWT_ROOT}/lib -l$${QWTLIB}
  59.  
  60. }
  61. #    LIBS +=  $${QWT_ROOT}/lib/qwtd5.dll
  62.    LIBS -lqwt5
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Application Output:
Starting e:/Data/QT_Creator_Projects/bin/DriveCycle.exe...
Invalid parameter passed to C runtime function.
Invalid parameter passed to C runtime function.

e:/Data/QT_Creator_Projects/bin/DriveCycle.exe exited with code 3

Much of the qwtInclude.pri was taken based on the data_plot example from the qwt-5.1.1 installed examples. As I said earlier, the example runs fine from its installed directory. So then I thought I would make a complete copy of the data_plot example in a new folder under qwt-5.1.1/examples called "mytest", in this folder I copied completely the main.cpp, data_plot.cpp, data_plot.h, and data_plot.pro; opened the pro file in qt creator and tried to run, which should be identical to the original example, and it duplicates the same error I experienced before. Any help/insight would be most welcome, I have been scouring the web looking for helpful hints related to this for a couple days now, which is partially why the pri file above has so many entries...

The only difference I have found so far between my 2 non-working versions and the working example is in the "Build Steps" -> "QMake"->"Arguments" (which are not changable from this screen):
Working example (qwt-5.1.1/examples/data_plot...):
"C:/qwt-5.1.1/examples/data_plot/data_plot.pro -spec win32-g++ -r"
Non-working examples (both) (qwt-5.1.1/examples/MyTest...):
"C:/qwt-5.1.1/examples/MyTest/data_plot.pro -spec win32-g++ -r CONFIG +=debug_and_release".

The only conclusions I have been able to draw from this so far is that the extra CONFIG statement must be a setting in QtCreator? Don't know if this is even remotely related to the issues I am seeing, just an observation.

Thanks to all in advance for the help, it is much appreciated!