Stepping in C++ does not work on Boot2Qt device

1. Create a new Qt Quick Application project using defaults.
2. Place a breakpoint in main.cpp at the line:

       QQmlApplicationEngine engine;
   

3. Start debugging this on a Boot2Qt device with Qt 5.6.2.
4. When the breakpoint is being hit, press F10 ("step over").
   You'll soon see a message box that the process was stopped because of a SIGTRAP signal. Creator will display the following lines in pthread_cond_wait.c:

   	  /* Wait until woken by signal or broadcast.  */
   	lll_futex_wait (&cond->__data.__futex, futex_val, pshared);
   

5. Press F5 ("continue").
   You won't be able to get the application running. At least I am not.

Stepping from the breakpoint should stop at the next line in the same file. After continuing, the application should start correctly.

Without the said breakpoint, the application will start correctly. Stepping at a breakpoint in QML works. Breakpoints in both, C++ and QML, work with a Boot2Qt device running Qt 5.9.1