[GHC] #15508: concprog001 fails with various errors

[GHC]

#15508: concprog001 fails with various errors
-------------------------------------+-------------------------------------
        Reporter:  osa1              |                Owner:  osa1
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.8.1
       Component:  Compiler          |              Version:  8.5
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Runtime crash     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #15571            |  Differential Rev(s):  Phab:D5051
       Wiki Page:                    |  (reverted), Phab:D5165, Phab:D5178
-------------------------------------+-------------------------------------

Comment (by simonmar):

 The code is getting the ccs for the AP_STACK closure from the update
 frame. I imagine the "ToDo" was to think about whether this is really the
 right thing. It shouldn't cause a crash - the CCS in the update frame
 should be valid - and I don't know where else we would get a useful CCS
 from for the AP_STACK, so it looks reasonable to me.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15508#comment:31>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler