[REG 3.6 -> 4.0] Debugger can't "step into"

1. Have a simple program:

   #include <QCoreApplication>
   #include <QDebug>
   
   void func(){
   
   }
   
   int main(int argc, char *argv[])
   {
       QCoreApplication a(argc, argv);
       func();
       qDebug() << "Program ran forward.";
   
       return a.exec();
   }
   

2. Place a breakpoint at the call to func().
3. Run this in the debugger.
4. When the debugger stopped at the breakpoint, press F11 to "step into".
   The debugger will not step in. It will go into "Running" state and print the qDebug().

The debugger should just step into the called function.