[GHC] #8684: hWaitForInput cannot be interrupted by async exceptions on unix

[GHC]

#8684: hWaitForInput cannot be interrupted by async exceptions on unix
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        Reporter:  nh2               |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Core Libraries    |              Version:  7.6.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:  13497, 13525      |             Blocking:
 Related Tickets:  #12912, #13525    |  Differential Rev(s):  Phab:D42
       Wiki Page:                    |
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Comment (by nh2):

 I've augmented my debugging output by the Windows thread ID
 [https://github.com/ghc/ghc/blob/ghc-8.2.1-release/rts/win32/OSThreads.c#L558
 here] and with `GetCurrentThreadId()`:

 {{{
 fdReady called with msecs = 5000
 calling WaitForSingleObject in windows thread id 0000000000000b14
 calling pCSIO(thread id 0000000000000b14)
 pCSIO ret 0
 pCSIO error: 1168
 WaitForSingleObject rc 258 (WAIT_TIMEOUT)
 }}}

 Looks like the thread IDs are the same, so I currently have no idea why
 `pCSIO()` running wouldn't switftly terminate the `WaitForSingleObject()`
 on this `FILE_TYPE_CHAR` FD.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8684#comment:26>
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