[GHC] #10010: LLVM/optimized code for sqrt incorrect for negative values

[GHC]

#10010: LLVM/optimized code for sqrt incorrect for negative values
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        Reporter:  glguy             |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (LLVM)   |              Version:  7.8.4
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect result  |  Unknown/Multiple
  at runtime                         |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by tjakway):

 This works for me on HEAD (f21eedbc223c33b71ba323a44c25fcd512f61b52)

 All of the below were tried with -O0, -O1, and -O2

 ghc 8.0.1 (doesn't support LLVM 3.8) and llvm 3.7 gives NaN
 HEAD with 3.7 also gives NaN
 HEAD with 3.8 gives NaN

 So at least it's OK going forward.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10010#comment:1>
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