[GHC] #11555: catch _|_ breaks at -O1

[GHC]

#11555: catch _|_ breaks at -O1
-------------------------------------+-------------------------------------
        Reporter:  slyfox            |                Owner:
            Type:  bug               |               Status:  closed
        Priority:  highest           |            Milestone:  8.0.1
       Component:  Compiler          |              Version:  8.0.1-rc2
      Resolution:  fixed             |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect result  |  Unknown/Multiple
  at runtime                         |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D1973
       Wiki Page:                    |
-------------------------------------+-------------------------------------

Comment (by Ben Gamari <ben@…>):

 In [changeset:"f091218ae14a24f9dbd991794c2da6377364578b/ghc" f091218/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="f091218ae14a24f9dbd991794c2da6377364578b"
 CLabel: Catch #11155 during C-- pretty-printing

 In #11555 we ended up generating references to the non-existence
 stg_ap_0_upd. Here we add asserts to verify that we don't generate
 references to non-existent selector or application symbols.

 It would likely also make sense to add further asserts during code
 generation, so we can catch the issue even closer to its source.

 Test Plan: Validate

 Reviewers: simonmar, austin, ezyang

 Reviewed By: simonmar, austin

 Subscribers: thomie

 Differential Revision: https://phabricator.haskell.org/D2230

 GHC Trac Issues: #11155
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11555#comment:23>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler