[GHC] #6156: Optimiser bug on linux-powerpc

[GHC]

#6156: Optimiser bug on linux-powerpc
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  Reporter:  erikd                        |          Owner:  pcapriotti
      Type:  bug                          |         Status:  new       
  Priority:  normal                       |      Milestone:  7.6.1     
 Component:  Compiler                     |        Version:  7.4.1     
Resolution:                               |       Keywords:            
        Os:  Linux                        |   Architecture:  powerpc   
   Failure:  Incorrect result at runtime  |     Difficulty:  Unknown   
  Testcase:                               |      Blockedby:            
  Blocking:                               |        Related:            
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Comment(by erikd):

 @simonpj : This is not a cryptocipher bug, its an GHC optimiser bug which
 was first found in the cryptocipher package. The code in the original bug
 report was a snippet of code from cryptocipher. Interestingly, the bug
 only shows itself on PowerPC.

 @pcapriotti : The testsuite file you updated
 (tests/codeGen/should_run/T5900.hs) probably won't trigger this bug,
 because in my testing, it would only appear when the function `fl`
 appeared in a separate module. Maybe a cross module inlining problem?

 Unfortunately I am not in a position to test this at the moment because
 whenever I try to compile GHC HEAD from git, I hit bug #6167.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/6156#comment:16>
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