[GHC] #13380: raiseIO# result looks wrong

[GHC]

#13380: raiseIO# result looks wrong
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        Reporter:  dfeuer            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.2.1
       Component:  Compiler          |              Version:  8.1
      Resolution:                    |             Keywords:  Exceptions
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Other             |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"7b087aeba45a7a70a5553ef4c116ee67660423e8/ghc" 7b087ae/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="7b087aeba45a7a70a5553ef4c116ee67660423e8"
 Make raiseIO# produce topRes

 Make `raiseIO#` produce `topRes` instead of `ExnRes`. `ExnRes` leads to
 demand analysis being too aggressive, IMO, allowing imprecise exceptions
 produced by `throw` to replace exceptions thrown by `throwIO` that
 would like to think of as precise.

 This fixes that, but is certanly much more conservative than we would
 ideally like. Let's see how bad it is.

 Fixes Trac #13380

 Reviewers: austin, bgamari

 Subscribers: rwbarton, thomie

 Differential Revision: https://phabricator.haskell.org/D3301
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13380#comment:6>
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