[GHC] #7944: GHC goes into an apparently infinite loop at -O2

[GHC]

#7944: GHC goes into an apparently infinite loop at -O2
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        Reporter:  bos               |                Owner:  (none)
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.9
      Resolution:                    |             Keywords:  SpecConstr
Operating System:  Unknown/Multiple  |         Architecture:  x86_64
 Type of failure:  Compile-time      |  (amd64)
  crash                              |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #5550 #8852       |  Differential Rev(s):  Phab:D3404
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"af941a96f62101a6539f3cc35d82df3fd964539c/ghc" af941a9/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="af941a96f62101a6539f3cc35d82df3fd964539c"
 Add regression test for #7944

 Commit b8b3e30a6eedf9f213b8a718573c4827cfa230ba happened to fix the bug
 reported in #7944. Let's add a regression test so that it stays that
 way.

 Fixes #7944.

 Test Plan: make test TEST=T7944

 Reviewers: austin, bgamari

 Reviewed By: bgamari

 Subscribers: rwbarton, thomie

 Differential Revision: https://phabricator.haskell.org/D3404
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7944#comment:15>
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