iOS: Qt Creator doesn't rebuild executable

Steps to reproduce:

• use a qtbase developer build
• build any project, e.g. the menus example as an external project and run it.
• make a change, e.g. add a qDebug() << _FUNCTION_;
• set a break point at the qDebug()
• hit "build" and start the application in debug mode and step over the new statement.
  => the debug message will not be printed
  => the debugger will behave as if the sources were newer than the executable

Workaround:

• have XCode open in parallel
• open and build the .xcodeproj tree.
• Now Creator will use the new build