QT 5.6 with OPenCV Run time 0xc0000139 - qt

Question

Anyone got QT 5.6 working with OpenCV ?
Tried OpenCV latest 2.4.13 (at time of writing) and went back to OpenCV 2.4.9.
None worked - program will compile, link but crash on "During Startup program exited with code 0xc0000139". I never had any problems with QT 5.5.1 and OpenCV.
Here is stripped down code:
**mainwindow.cpp:**
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <opencv/cv.h>
#include <opencv2/highgui/highgui.hpp>
using namespace cv;
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
cv::Mat image = cv::imread("C:/Users/foo/pics/cheetah.jpg");
cv::namedWindow("My Image");
cv::imshow("My Image", image);
cvWaitKey(0);
}
MainWindow::~MainWindow()
{
delete ui;
}
**main.cpp (used default):**
#include "mainwindow.h"
#include <QApplication>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
MainWindow w;
w.show();
return a.exec();
}
**mainwindow.h: (used default)**
#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QMainWindow>
namespace Ui {
class MainWindow;
}
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
explicit MainWindow(QWidget *parent = 0);
~MainWindow();
private:
Ui::MainWindow *ui;
};
#endif // MAINWINDOW_H
**test_opencv.pro:**
INCLUDEPATH += "C:\Users\foo\Downloads\opencv\build\include"
LIBS += -LC:\Users\foo\Downloads\opencv\build\lib \
-lopencv_core249.dll \
-lopencv_highgui249.dll \
-lopencv_imgproc249.dll \
-lopencv_features2d249.dll \
-lopencv_video249.dll \
-lopencv_calib3d249.dll
QT += core gui
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
TARGET = test_opencv
TEMPLATE = app
SOURCES += main.cpp\
mainwindow.cpp
HEADERS += mainwindow.h
FORMS += mainwindow.ui
Path set:
C:\Qt\Tools\mingw492_32\bin
C:\Qt\5.6\mingw49_32\bin
C:\Users\foo\Downloads\opencv\build\bin
QT works fine with no OpenCV calls. With above code, running with QT Debug will see this:
"During Startup program exited with code 0xc0000139".
QT Error message
I have double checked my path. The OpenCV DLLs are defined in the Path. problem is not about not finding the runtime dynamically link dlls. I also checked my System32 and other directories for any old OpenCV dlls that might interfere as the path is traversed. No issues.
OpenCV was built with CMake and successfully build and installed. No issues there.
Thanks
Sean