[GHC] #8089: Implementation of GHC.Event.Poll.poll is broken due to bad coercion

[GHC]

#8089: Implementation of GHC.Event.Poll.poll is broken due to bad coercion
-------------------------------------+-------------------------------------
        Reporter:  merijn            |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:  7.10.1
       Component:  libraries/base    |              Version:  7.6.3
      Resolution:  fixed             |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Runtime crash     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D407
       Wiki Page:                    |
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Comment (by alpmestan):

 For the record, the test in question is:

 {{{#!hs
 -- can be found in libraries/base/tests/T8089.hs
 import Control.Concurrent

 main :: IO ()
 main = threadDelay maxBound
 }}}

 Building it (I copied the CLI arguments from the threaded1 run):

 {{{
 $ inplace/bin/ghc-stage2 -o T8089 libraries/base/tests/T8089.hs -dcore-
 lint -dcmm-lint -no-user-package-db -rtsopts -fno-warn-missed-
 specialisations -fshow-warning-groups -fdiagnostics-color=never -fno-
 diagnostics-show-caret -dno-debug-output  -threaded -debug
 [1 of 1] Compiling Main             ( libraries/base/tests/T8089.hs,
 libraries/base/tests/T8089.o )
 Linking T8089 ...
 }}}

 Running it:

 {{{
 $ ./T8089
 $ echo $?
 0
 }}}

 (the expected return code is 99, we get 0)

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8089#comment:18>
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