LLDB: Mixed debugging on Linux broken

Steps to reproduce:

• create Qt Quick Application from template (I've used Quick 1.2, Qt 5.3.2 kit)
• set bp to engine.load() in main.cpp and to the onTriggered statements in main.qml
• start debugging

Current result:

• debugger fails to come up (see attached log, when log prints only 'sQML Debugger: No application output received in time, trying to connect ...' I've pressed 'Stop Debugging')