Impossible to interrupt or stop lldb using Qt5 kit

Steps to reproduce:

• create kit using Qt5 and lldb engine
• create/open Qt Gui Application (I've used template from wizard)
• set some breakpoints
• start debugging
• (breakpoints won't be hit)
• try to interrupt the lldb
• wait some time and try to stop llbd

Expected result:

• it's possible to interrupt lldb to see some locals or evaluate some expressions
• it's possible to stop lldb

Current result:

• interrupting does not happen
• stopping fails (stop happens only when closing the inferior)