Using openCV, timed out waiting for gdb reply

This very simple code

#include <opencv2/core/core.hpp>

int main()
{
    while (1)
    {
        cv::Point2d a(0.0,0.0);
        cv::Point2d b(1.0,1.0);
        a = a + b;
        cv::Mat flipImg;
    }
    return 0;
}

is compiled with this command line,

g++ -I/usr/local/include/opencv2 -L/usr/local/lib/ -g -o exec.x main.cpp -lopencv_core -std=c++11

on Ubuntu 14.04, with gcc version 4.8.4 (Ubuntu 4.8.4-2ubuntu1~14.04.3).

After executing exec.x, I do "Attach to running application" in qtcreator and I select the process.

The GNU gdb version is (Ubuntu 7.7.1-0ubuntu5~14.04.3) 7.7.1

I set a breakpoint inside the While and I iterate over the lines using F10. I get the bug when trying to go from line a = a + b; to line cv::Mat flipImg;.