[GHC] #11444: 8.0 rc1 panics in applyTypeToArgs

[GHC]

#11444: 8.0 rc1 panics in applyTypeToArgs
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        Reporter:  osa1              |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.2.1
       Component:  Compiler          |              Version:  8.0.1-rc1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #13027            |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 > In particular, we probably never want a pointer equality test to float
 out of a case on one of `reallyUnsafePtrEq`'s arguments.

 OK.  Fix that in `primops.txt.pp` by giving `reallyUnsafePtrEq` a
 `can_fail` attribute.

 That sounds a bit odd, but read `Note [dataToTag#]` in `primops.txt.pp`,
 and `Note [PrimOp can_fail and has_side_effects]` in `PrimOp.h`, and
 expecially `Note [Transformations affected by can_fail and
 has_side_effects]` in `PrimOp.hs`.

 Would you like to do that?  Add a Note obviously with your example above.
 Maybe make a new ticket.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11444#comment:15>
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