LLDB debugging kind of broken

Steps to reproduce:

• create (any) desktop application from template (Widget/Console/Quick)
• start debugger (with / without breakpoints set)

Current result:

• sometimes debugger fails to start up correctly (seems as if debugger engine is trying to send commands to the lldb but lldb is not receiving them)
  • typing int into the debugger command line edit makes it continue in 99% of the cases - otherwise you have to
  • stop by hitting the 'x' at the progress bar (or abort debugging) and re-run debugging
• sometimes debugger fails to continue from an interrupted state
  • typing cont into the debugger command line edit makes it continue in 99% of the cases

• debugging console applications seems to fail always when 'Run in Terminal' is enabled, but seems to work without

Note: All of the above work fine with 10.10 / Xcode 6.x.