[MacPorts] #70375: dragon crashes on launch

[MacPorts]

#70375: dragon crashes on launch
---------------------------+--------------------
  Reporter:  barracuda156  |      Owner:  (none)
      Type:  defect        |     Status:  new
  Priority:  Normal        |  Milestone:
 Component:  ports         |    Version:  2.9.3
Resolution:                |   Keywords:  kde
      Port:  dragon        |
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Comment (by RJVB):

 You have at least 1 problem here: phonon doesn't seem to have a backend to
 talk to an actual audio device. For KDE the VLC backend is preferred, but
 that requires libVLC (which may or may not be available anymore after your
 changes to the VLC port[s]).

 Are you using an X11 version of Qt4, or is there another reason why X11 is
 getting involved? If the former: I have no idea how it handles X11 errors,
 but it's possible that it just does an `abort()` whenever one occurs and
 the application didn't provide its own handler. I started getting crashes
 like that from GTk applications after a recent upgrade to GTk3 (and
 apparently sideways related to me running Qt5 apps under X). I patched in
 an error handler that just prints the message and then continues (into
 GTk3, so any application that provides its own should still override
 that). See `XSetIOErrorExitHandler()`.

 The only thing of the sort that I had to do with Qt5 was to do a regular
 `exit()` rather than an `abort()` when no `DISPLAY` is defined (and I do
 get my share of these "failed request" warnings), so it would surprise me
 a bit if that were different in Qt4.

-- 
Ticket URL: <https://trac.macports.org/ticket/70375#comment:1>
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