[GHC] #14356: "Main: thread blocked indefinitely in an MVar operation" in fixIO

[GHC]

#14356: "Main: thread blocked indefinitely in an MVar operation" in fixIO
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        Reporter:  nickkuk           |                Owner:  (none)
            Type:  bug               |               Status:  patch
        Priority:  low               |            Milestone:
       Component:  Runtime System    |              Version:  8.2.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Poor/confusing    |  Unknown/Multiple
  error message                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D4113
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"b938576d151731b85314987fc550c17cfe824178/ghc" b938576/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="b938576d151731b85314987fc550c17cfe824178"
 Add custom exception for fixIO

 Traditionally, `fixIO f` throws `BlockedIndefinitelyOnMVar` if
 `f` is strict. This is not particularly friendly, since the
 `MVar` in question is just part of the way `fixIO` happens to be
 implemented. Instead, throw a new `FixIOException` with a better
 explanation of the problem.

 Reviewers: austin, hvr, bgamari

 Subscribers: rwbarton, thomie

 GHC Trac Issues: #14356

 Differential Revision: https://phabricator.haskell.org/D4113
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14356#comment:10>
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