-exec-finish in 'main' results (correctly) in something like
 40^error,msg="\"finish\" not meaningful in the outermost frame."
However, this message does not seem to get flushed before
anything else happens - i.e. "never". So force some extra output
that's known to trigger a flush.

Change-Id: I3f5ef6f7cc57dd085976b239f18d6ec7bd108972
Reviewed-by: Niels Weber <niels.weber@theqtcompany.com>