[GHC] #14998: Sort out the strictness mess for exceptions

[GHC]

#14998: Sort out the strictness mess for exceptions
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        Reporter:  simonpj           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.4.3
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:  Exceptions
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by sgraf):

 As expressed in Phab:D4574#126789 I have doubts that we should really
 merge the diff for item 2. According to `#exceptions_and_strictness#` in
 GHC.IO `catchException` and `catchAny` have that bang on purpose, as a
 helper function when `catch#` moved to a lazy signature in #11555.
 ticket:11222#comment:6 is very relevant. Such a `raiseIO#` is exactly what
 `catchException` and `catchAny` would need.

 Somewhere above, I discovered that `GHC.IO.Handle.Internals.want*Handle`
 aren't strict in their `act`ions. I'm currently evaluating any performance
 benefits by adding bangs in appropriate positions.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14998#comment:19>
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